Assessment of the Effectiveness of Identity-Based Public Health Announcements in Increasing the Likelihood of Complying With COVID-19 Guidelines: Randomized Controlled Cross-sectional Web-Based Study

Background Public health campaigns aimed at curbing the spread of COVID-19 are important in reducing disease transmission, but traditional information-based campaigns have received unexpectedly extreme backlash. Objective This study aimed to investigate whether customizing of public service announcements (PSAs) providing health guidelines to match individuals’ identities increases their compliance. Methods We conducted a within- and between-subjects, randomized controlled cross-sectional, web-based study in July 2020. Participants viewed two PSAs: one advocating wearing a mask in public settings and one advocating staying at home. The control PSA only provided information, and the treatment PSAs were designed to appeal to the identities held by individuals; that is, either a Christian identity or an economically motivated identity. Participants were asked about their identity and then provided a control PSA and treatment PSA matching their identity, in random order. The PSAs were of approximately 100 words. Results We recruited 300 social media users from Amazon Mechanical Turk in accordance with usual protocols to ensure data quality. In total, 8 failed the data quality checks, and the remaining 292 were included in the analysis. In the identity-based PSA, the source of the PSA was changed, and a phrase of approximately 12 words relevant to the individual’s identity was inserted. A PSA tailored for Christians, when matched with a Christian identity, increased the likelihood of compliance by 12 percentage points. A PSA that focused on economic values, when shown to individuals who identified as economically motivated, increased the likelihood of compliance by 6 points. Conclusions Using social media to deliver COVID-19 public health announcements customized to individuals’ identities is a promising measure to increase compliance with public health guidelines. Trial Registration ISRCTN Registry 22331899; https://www.isrctn.com/ISRCTN22331899.


1a-i) Identify the mode of delivery in the title
Identify the mode of delivery. Preferably use "web-based" and/or "mobile" and/or "electronic game" in the title. Avoid ambiguous terms like "online", "virtual", "interactive". Use "Internet-based" only if Intervention includes non-web-based Internet components (e.g. email), use "computer-based" or "electronic" only if offline products are used. Use "virtual" only in the context of "virtual reality" (3-D worlds). Use "online" only in the context of "online support groups". Complement or substitute product names with broader terms for the class of products (such as "mobile" or "smart phone" instead of "iphone"), especially if the application runs on different platforms.

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Does your paper address subitem 1a-i? * Copy and paste relevant sections from manuscript title (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study 1 2 3 4 5 essential subitem not at all important 1 2 3 4 5 essential 1a-ii) Non-web-based components or important co-interventions in title Mention non-web-based components or important co-interventions in title, if any (e.g., "with telephone support").

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Does your paper address subitem 1a-ii?
Copy and paste relevant sections from manuscript title (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No. it is not relevant. No. it is not relevant.

1a-iii) Primary condition or target group in the title
Mention primary condition or target group in the title, if any (e.g., "for children with Type I Diabetes") Example: A Web-based and Mobile Intervention with Telephone Support for Children with Type I Diabetes: Randomized Controlled Trial

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Does your paper address subitem 1a-iii? * Copy and paste relevant sections from manuscript title (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study 1b) ABSTRACT: Structured summary of trial design, methods, results, and conclusions NPT extension: Description of experimental treatment, comparator, care providers, centers, and blinding status.
subitem not at all important

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Does your paper address subitem 1b-i? * Copy and paste relevant sections from the manuscript abstract (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study Yes. "Participants viewed two PSA, one advocating wearing a mask in public settings and one staying at home. The control PSA provided information only, and the treatment PSA was designed to appeal to the identities held by individuals, either a Christian identity or an economically-motivated identity. Participants were asked about their identity and then received a control PSA and treatment PSA matching their identity in random order. The PSAs were about 100 words in length." 1 2 3 4 5 essential subitem not at all important 1 2 3 4 5 essential 1b-ii) Level of human involvement in the METHODS section of the ABSTRACT Clarify the level of human involvement in the abstract, e.g., use phrases like "fully automated" vs. "therapist/nurse/care provider/physician-assisted" (mention number and expertise of providers involved, if any). (Note: Only report in the abstract what the main paper is reporting. If this information is missing from the main body of text, consider adding it)

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Does your paper address subitem 1b-ii?
Copy and paste relevant sections from the manuscript abstract (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study Not relevant to the study. User read the text on their own.
1b-iii) Open vs. closed, web-based (self-assessment) vs. face-to-face assessments in the METHODS section of the ABSTRACT Mention how participants were recruited (online vs. offline), e.g., from an open access website or from a clinic or a closed online user group (closed usergroup trial), and clarify if this was a purely web-based trial, or there were face-to-face components (as part of the intervention or for assessment). Clearly say if outcomes were self-assessed through questionnaires (as common in web-based trials). Note: In traditional offline trials, an open trial (open-label trial) is a type of clinical trial in which both the researchers and participants know which treatment is being administered. To avoid confusion, use "blinded" or "unblinded" to indicated the level of blinding instead of "open", as "open" in web-based trials usually refers to "open access" (i.e. participants can self-enrol). (Note: Only report in the abstract what the main paper is reporting. If this information is missing from the main body of text, consider adding it) 1 2 3 4 5 essential Does your paper address subitem 1b-iii?
Copy and paste relevant sections from the manuscript abstract (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study yes. "We recruited 300 social media users from Amazon Mechanical Turk following usual protocols to ensure data quality" 1b-iv) RESULTS section in abstract must contain use data Report number of participants enrolled/assessed in each group, the use/uptake of the intervention (e.g., attrition/adherence metrics, use over time, number of logins etc.), in addition to primary/secondary outcomes. (Note: Only report in the abstract what the main paper is reporting. If this information is missing from the main body of text, consider adding it)

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Does your paper address subitem 1b-iv?
Copy and paste relevant sections from the manuscript abstract (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study yes."Participants viewed two PSA, one advocating wearing a mask in public settings and one staying at home. " and "Eight failed the data quality checks, leaving 292 for the analysis. " CONSORT-EHEALTH (V 1.6.1) -Submission/Publication

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Does your paper address subitem 1b-v?
Copy and paste relevant sections from the manuscript abstract (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study yes. "A PSA tailored for Christians, when matched with a Christian identity, increased the likelihood of complying by 12 percentage points. A PSA that focused on economic values, when shown to individuals who identified as economically motivated, increased the likelihood of complying by 6 points." 1 2 3 4 5 essential 2a-i) Problem and the type of system/solution Describe the problem and the type of system/solution that is object of the study: intended as stand-alone intervention vs. incorporated in broader health care program? Intended for a particular patient population? Goals of the intervention, e.g., being more cost-effective to other interventions, replace or complement other solutions? (Note: Details about the intervention are provided in "Methods" under 5)

Does your paper address subitem 2a-i? *
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study yes. "Public compliance with recommended actions to limit the spread of severe acute respiratory syndrome coronavirus 2 (SARSCoV-2) and the associated infectious disease  is an important component in the fight against the disease [1]. Current guidelines suggest several actions, such as wearing a mask and staying at home [2], yet far too many individuals fail to follow the advice provided by public health officials [3]. Public compliance to guidelines remains an issue [3][4][5].
Public Service Announcements (PSAs) have long been used to promote public health behaviors, although their success and the success of PSAs in general have been mixed [6]. Information-based PSAs are often successful because they present facts about the nature of a threat, explain the benefits of a response, and provide a clear call to action [7]. But is presenting information sufficient in a post-truth era as the world battles the COVID-19 pandemic? There has been strong backlash against wearing masks and staying at home [3,5], and "irrational behavior in non-compliance with COVID-19 policies" [8]. Psychological reactance occurs when individuals feel that previously permitted behaviors are constrained by an external agent, impugning their freedom [9,10]. They resist the constraint and try to regain the lost freedom [9, 10]. Thus, rather than helping, a PSA could backfire by sparking reactance that triggers individuals to eschew the recommended behavior and even actively work to impair compliance [11]. The likelihood of reactance may also be increased by the divisions in the United States along ideological lines, with stark differences in the extent to which those on the political left and political right believe that COVID-19 is a real threat [1,[12][13][14]. In the era of tribalism and distrust of experts, identity has become as central to many arguments as science-based information [14][15][16]. The interaction of an individual's identity with the source and content of the message can shape responses as much as the information it contains [17,18]. Individuals' identities determine how they answer the question "who am I?" [19][20][21]. According to social identity theory, these answers are dependent upon both their social identities and personal identities [19][20][21][22]. Social identities come from the social groups to which individuals belong [22], such as race, nationality, and organizational or religious affiliations [23][24][25]. Personal identities come from values individuals hold dear [20,25,26], such as volunteering [27], environmentalism [28], or the economy and economic values [29][30][31]. Both social and personal identities can be powerful forces that influence behavior because people are motivated to act in ways that align with their identity in order to maintain a sense of self-consistency [22,25,32,33]. Persuasive messages such as PSAs can take advantage of this desire for identity-consistent actions by framing a proposed action as being consistent with individuals' social or personal identities [34]. Speaking the language of an identity by using terms and arguments associated with the identity may make a message more persuasive [35]. Framing the advocated action as identity-consistent can further encourage individuals to adopt the desired behavior [34], because once you know how others with the same identity act, it is easier to convince yourself to act in that same way [1]. Thus, identity-framed messages become more persuasive [35]. We investigate whether customizing PSAs by using the source and language of a social identity (specifically Christian) or a personal identity (specifically economically-motivated) will increase the intention of individuals who identify with those identities to comply with the behaviors advocated by a PSA. We selected these identities because religious [36,37]  Yes. "Public compliance with recommended actions to limit the spread of severe acute respiratory syndrome coronavirus 2 (SARSCoV-2) and the associated infectious disease (COVID-19) is an important component in the fight against the disease [1]. Current guidelines suggest several actions, such as wearing a mask and staying at home [2], yet far too many individuals fail to follow the advice provided by public health officials [3]. Public compliance to guidelines remains an issue [3][4][5].
Public Service Announcements (PSAs) have long been used to promote public health behaviors, although their success and the success of PSAs in general have been mixed [6]. Information-based PSAs are often successful because they present facts about the nature of a threat, explain the benefits of a response, and provide a clear call to action [7]. But is presenting information sufficient in a post-truth era as the world battles the COVID-19 pandemic? There has been strong backlash against wearing masks and staying at home [3,5], and "irrational behavior in non-compliance with COVID-19 policies" [8]. Psychological reactance occurs when individuals feel that previously permitted behaviors are constrained by an external agent, impugning their freedom [9,10]. They resist the constraint and try to regain the lost freedom [9, 10]. Thus, rather than helping, a PSA could backfire by sparking reactance that triggers individuals to eschew the recommended behavior and even actively work to impair compliance [11]. The likelihood of reactance may also be increased by the divisions in the United States along ideological lines, with stark differences in the extent to which those on the political left and political right believe that COVID-19 is a real threat [1,[12][13][14]. In the era of tribalism and distrust of experts, identity has become as central to many arguments as science-based information [14][15][16]. The interaction of an individual's identity with the source and content of the message can shape responses as much as the information it contains [17,18]. Individuals' identities determine how they answer the question "who am I?" [19][20][21]. According to social identity theory, these answers are dependent upon both their social identities and personal identities [19][20][21][22] [29][30][31]. Both social and personal identities can be powerful forces that influence behavior because people are motivated to act in ways that align with their identity in order to maintain a sense of self-consistency [22,25,32,33]. Persuasive messages such as PSAs can take advantage of this desire for identity-consistent actions by framing a proposed action as being consistent with individuals' social or personal identities [34]. Speaking the language of an identity by using terms and arguments associated with the identity may make a message more persuasive [35]. Framing the advocated action as identity-consistent can further encourage individuals to adopt the desired behavior [34], because once you know how others with the same identity act, it is easier to convince yourself to act in that same way [1]. Thus, identity-framed messages become more persuasive [35]. We investigate whether customizing PSAs by using the source and language of a social identity (specifically Christian) or a personal identity (specifically economically-motivated) will increase the intention of individuals who identify with those identities to comply with the behaviors advocated by a PSA. We selected these identities because religious [36,37] and economic [38] excuses are frequently provided by individuals who resist public health guidelines. If individuals who hold these identities could be persuaded to follow public health guidance, the benefits could be substantial [39]. Our research question is: Does 2b) In INTRODUCTION: Specific objectives or hypotheses METHODS 3a) Description of trial design (such as parallel, factorial) including allocation ratio Does your paper address CONSORT subitem 2b? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study yes. "Our research question is: Does framing a PSA using a Christian social identity or an economically-motivated personal identity increase the likelihood of compliance with COVID-19 guidelines by individuals who hold those identities?" Does your paper address CONSORT subitem 3a? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study Yes. "We conducted a within-and between-subjects controlled randomized cross-sectional online experiment." and "At the beginning of the survey, subjects were asked a series of questions to ascertain their identification with Christianity and with the Economic Health of the country (our selected identities). Participants were assigned to either the Christianframed treatment or the economics-framed treatment depending on which identity they identified with more. If subjects identified with both identities equally, the participants were randomly assigned to one of the two treatments. " 3b) Important changes to methods after trial commencement (such as eligibility criteria), with reasons subitem not at all important 1 2 3 4 5 essential 4a) Eligibility criteria for participants Does your paper address CONSORT subitem 3b? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No. There were no changes to methods after commencement.

3b-i) Bug fixes, Downtimes, Content Changes
Bug fixes, Downtimes, Content Changes: ehealth systems are often dynamic systems. A description of changes to methods therefore also includes important changes made on the intervention or comparator during the trial (e.g., major bug fixes or changes in the functionality or content) (5-iii) and other "unexpected events" that may have influenced study design such as staff changes, system failures/downtimes, etc. [2].

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Does your paper address subitem 3b-i?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No. Not relevant to our study CONSORT-EHEALTH (V 1.6.1) -Submission/Publication Form https://docs.google.com/forms/d/e/1FAIpQLSfZBSUp1bwOc_OimqcS6... 1 2 3 4 5 essential Does your paper address CONSORT subitem 4a? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study yes. "we recruited 300 participants from Amazon Mechanical Turk following usual protocols to ensure data quality [40]. We recruited participants only from the United States who held an Amazon Masters classification and included a CAPTCHA to preclude non-human responses. Participants were paid $1.25 and spent an average of about 13 minutes doing the study (minimum 3.6 minutes, maximum 11 hours). Eight subjects failed one or more of the three attention checks (that asked participants to select specific answers), leaving 292 participants. "

4a-i) Computer / Internet literacy
Computer / Internet literacy is often an implicit "de facto" eligibility criterion -this should be explicitly clarified.

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Does your paper address subitem 4a-i?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No. it is not relevant to our study.
CONSORT-EHEALTH (V 1.6.1) -Submission/Publication Form https://docs.google.com/forms/d/e/1FAIpQLSfZBSUp1bwOc_OimqcS6... Open vs. closed, web-based vs. face-to-face assessments: Mention how participants were recruited (online vs. offline), e.g., from an open access website or from a clinic, and clarify if this was a purely webbased trial, or there were face-to-face components (as part of the intervention or for assessment), i.e., to what degree got the study team to know the participant. In online-only trials, clarify if participants were quasi-anonymous and whether having multiple identities was possible or whether technical or logistical measures (e.g., cookies, email confirmation, phone calls) were used to detect/prevent these.

Does your paper address subitem 4a-ii? *
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study Yes. "we recruited 300 participants from Amazon Mechanical Turk following usual protocols to ensure data quality [40]. We recruited participants only from the United States who held an Amazon Masters classification and included a CAPTCHA to preclude non-human responses. Participants were paid $1.25 and spent an average of about 13 minutes doing the study (minimum 3.6 minutes, maximum 11 hours). Eight subjects failed one or more of the three attention checks (that asked participants to select specific answers), leaving 292 participants. "

4a-iii) Information giving during recruitment
Information given during recruitment. Specify how participants were briefed for recruitment and in the informed consent procedures (e.g., publish the informed consent documentation as appendix, see also item X26), as this information may have an effect on user self-selection, user expectation and may also bias results.

4b) Settings and locations where the data were collected
subitem not at all important 1 2 3 4 5 essential Does your paper address subitem 4a-iii?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study

Yes. The Study Information Sheet is included with pre-registration
Does your paper address CONSORT subitem 4b? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study Yes. "we recruited 300 participants from Amazon Mechanical Turk " 4b-i) Report if outcomes were (self-)assessed through online questionnaires Clearly report if outcomes were (self-)assessed through online questionnaires (as common in web-based trials) or otherwise.

Clear selection
Does your paper address subitem 4b-i? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study yes. "After reading each PSA, participants reported to what extent they would engage in the advocated behavior. " CONSORT-EHEALTH (V 1.6.1) -Submission/Publication

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Does your paper address subitem 4b-ii?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study yes. "One PSA was a control PSA with information purportedly from the US Public Health Service" "The identity-framed PSA added a single short phrase designed to appeal either to people who held a Christian social identity (purportedly written by the Chaplain of the US Senate) or to those for whom protecting the country's economy was a central part of their personal identity (purportedly written by the US Chamber of Commerce). " CONSORT-EHEALTH (V 1.6.1) -Submission/Publication

Clear selection
Does your paper address subitem 5-i?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study yes. "One PSA was a control PSA with information purportedly from the US Public Health Service" "The identity-framed PSA added a single short phrase designed to appeal either to people who held a Christian social identity (purportedly written by the Chaplain of the US Senate) or to those for whom protecting the country's economy was a central part of their personal identity (purportedly written by the US Chamber of Commerce). "

5-ii) Describe the history/development process
Describe the history/development process of the application and previous formative evaluations (e.g., focus groups, usability testing), as these will have an impact on adoption/use rates and help with interpreting results.
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No. We did one pilot test and then ran the study.

5-iii) Revisions and updating
Revisions and updating. Clearly mention the date and/or version number of the application/intervention (and comparator, if applicable) evaluated, or describe whether the intervention underwent major changes during the evaluation process, or whether the development and/or content was "frozen" during the trial.
Describe dynamic components such as news feeds or changing content which may have an impact on the replicability of the intervention (for unexpected events see item 3b).

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Does your paper address subitem 5-iii?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study no. The PSA were not changed during the study.

5-iv) Quality assurance methods
Provide information on quality assurance methods to ensure accuracy and quality of information provided [1], if applicable.
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study yes. "In July, 2020, we recruited 300 participants from Amazon Mechanical Turk following usual protocols to ensure data quality [40]. We recruited participants only from the United States who held an Amazon Masters classification and included a CAPTCHA to preclude non-human responses. Participants were paid $1.25 and spent an average of about 13 minutes doing the study (minimum 3.6 minutes, maximum 11 hours). Eight subjects failed one or more of the three attention checks (that asked participants to select specific answers), leaving 292 participants. " 5-v) Ensure replicability by publishing the source code, and/or providing screenshots/screen-capture video, and/or providing flowcharts of the algorithms used Ensure replicability by publishing the source code, and/or providing screenshots/screen-capture video, and/or providing flowcharts of the algorithms used. Replicability (i.e., other researchers should in principle be able to replicate the study) is a hallmark of scientific reporting.

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Does your paper address subitem 5-v?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study yes. the appendix contains the PSA CONSORT-EHEALTH (V 1.6.1) -Submission/Publication Form https://docs.google.com/forms/d/e/1FAIpQLSfZBSUp1bwOc_OimqcS6...

5-vi) Digital preservation
Digital preservation: Provide the URL of the application, but as the intervention is likely to change or disappear over the course of the years; also make sure the intervention is archived (Internet Archive, webcitation.org, and/or publishing the source code or screenshots/videos alongside the article). As pages behind login screens cannot be archived, consider creating demo pages which are accessible without login.

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Does your paper address subitem 5-vi?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study Not relevant to our study. There is no application. the intervention is the PSA in the appendix.

5-vii) Access
Access: Describe how participants accessed the application, in what setting/context, if they had to pay (or were paid) or not, whether they had to be a member of specific group. If known, describe how participants obtained "access to the platform and Internet" [1]. To ensure access for editors/reviewers /readers, consider to provide a "backdoor" login account or demo mode for reviewers/readers to explore the application (also important for archiving purposes, see vi).

Clear selection
Does your paper address subitem 5-viii? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study Yes. "we recruited 300 participants from Amazon Mechanical Turk" the study lasted 3-5 minutes. We provide the full intervention and control in the Appendix CONSORT-EHEALTH (V 1.6.1) -Submission/Publication Form https://docs.google.com/forms/d/e/1FAIpQLSfZBSUp1bwOc_OimqcS6...

5-ix) Describe use parameters
Describe use parameters (e.g., intended "doses" and optimal timing for use). Clarify what instructions or recommendations were given to the user, e.g., regarding timing, frequency, heaviness of use, if any, or was the intervention used ad libitum.

Clear selection
Does your paper address subitem 5-ix?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study This is not relevant to our study. Subjects viewed the PSAs only once

5-x) Clarify the level of human involvement
Clarify the level of human involvement (care providers or health professionals, also technical assistance) in the e-intervention or as co-intervention (detail number and expertise of professionals involved, if any, as well as "type of assistance offered, the timing and frequency of the support, how it is initiated, and the medium by which the assistance is delivered". It may be necessary to distinguish between the level of human involvement required for the trial, and the level of human involvement required for a routine application outside of a RCT setting (discuss under item 21 -generalizability).
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study This is not relevant to our study. Subjects viewed the PSAs online

5-xi) Report any prompts/reminders used
Report any prompts/reminders used: Clarify if there were prompts (letters, emails, phone calls, SMS) to use the application, what triggered them, frequency etc. It may be necessary to distinguish between the level of prompts/reminders required for the trial, and the level of prompts/reminders for a routine application outside of a RCT setting (discuss under item 21 -generalizability).

Clear selection
Does your paper address subitem 5-xi? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study This is not relevant to our study. Subjects viewed the PSAs only once CONSORT-EHEALTH (V 1.6.1) -Submission/Publication Form https://docs.google.com/forms/d/e/1FAIpQLSfZBSUp1bwOc_OimqcS6... Describe any co-interventions (incl. training/support): Clearly state any interventions that are provided in addition to the targeted eHealth intervention, as ehealth intervention may not be designed as stand-alone intervention. This includes training sessions and support [1]. It may be necessary to distinguish between the level of training required for the trial, and the level of training for a routine application outside of a RCT setting (discuss under item 21 -generalizability.

Clear selection
Does your paper address subitem 5-xii? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study This is not relevant to our study. Subjects viewed the PSAs only once CONSORT-EHEALTH (V 1.6.1) -Submission/Publication Form https://docs.google.com/forms/d/e/1FAIpQLSfZBSUp1bwOc_OimqcS6...

Does your paper address CONSORT subitem 6a? *
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study Yes. the specific items are in the Appendix. ". Mask Compliance -Adapted from Dennis, et al., 2017 andVenkatesh, et al., 2003 Please rate your agreement with each of the following statements [0: Strongly Disagree -100: Strongly Agree] I intend to wear a mask whenever I am in public and around other people I predict I will wear a mask whenever I am in public and around other people I plan to wear a mask whenever I am in public and around other people Wearing a mask whenever I am in public and around other people will be part of my usual routine I will recommend to others that they wear a mask whenever I am in public and around other people I will advocate for wearing a mask whenever I am in public and around other people Wearing a mask whenever I am in public and around other people is an appropriate thing to do 4. Stay-at-home Compliance -Adapted from Dennis, et al., 2017 andVenkatesh, et al., 2003 Please rate your agreement with each of the following statements [0: Strongly Disagree -100: Strongly Agree] I intend to remain at home as much as possible I predict I will remain at home as much as possible I plan to remain at home as much as possible Remaining at home as much as possible will be part of my usual routine I will recommend remaining at home as much as possible to others I will advocate for remaining at home as much as possible Remaining at home as much as possible is an appropriate o"thing to d 6a-ii) Describe whether and how "use" (including intensity of use/dosage) was defined/measured/monitored Describe whether and how "use" (including intensity of use/dosage) was defined/measured/monitored (logins, logfile analysis, etc.). Use/adoption metrics are important process outcomes that should be reported in any ehealth trial.

Copy and paste relevant sections from manuscript text
This is not relevant to our study. Subjects viewed the PSAs only once 6a-iii) Describe whether, how, and when qualitative feedback from participants was obtained Describe whether, how, and when qualitative feedback from participants was obtained (e.g., through emails, feedback forms, interviews, focus groups).

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Does your paper address subitem 6a-iii?

Copy and paste relevant sections from manuscript text
No, we did not seek qualitative feedback Does your paper address CONSORT subitem 6b? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study There were no changes once data collection began CONSORT-EHEALTH (V 1.6.1) -Submission/Publication Form https://docs.google.com/forms/d/e/1FAIpQLSfZBSUp1bwOc_OimqcS6...

7a) How sample size was determined
NPT: When applicable, details of whether and how the clustering by care provides or centers was addressed subitem not at all important 1 2 3 4 5 essential 7b) When applicable, explanation of any interim analyses and stopping guidelines 7a-i) Describe whether and how expected attrition was taken into account when calculating the sample size Describe whether and how expected attrition was taken into account when calculating the sample size.

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Does your paper address subitem 7a-i?
Copy and paste relevant sections from manuscript title (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study Yes. "A power analysis using G*Power [47] determined that a 300 participant sample using this design would provide a power of .93 to detect a small effect size (f=.10). " Does your paper address CONSORT subitem 7b? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No. We had no interim analyses and stopping guidelines CONSORT-EHEALTH (V 1.6.1) -Submission/Publication Form https://docs.google.com/forms/d/e/1FAIpQLSfZBSUp1bwOc_OimqcS6... 8a) Method used to generate the random allocation sequence NPT: When applicable, how care providers were allocated to each trial group 8b) Type of randomisation; details of any restriction (such as blocking and block size) 9) Mechanism used to implement the random allocation sequence (such as sequentially numbered containers), describing any steps taken to conceal the sequence until interventions were assigned Does your paper address CONSORT subitem 8a? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No. randomization was done using the Qualtrics randomizer function Does your paper address CONSORT subitem 8b? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No. randomization was done using the Qualtrics randomizer function Does your paper address CONSORT subitem 9? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No. randomization was done using the Qualtrics randomizer function CONSORT-EHEALTH (V 1.6.1) -Submission/Publication Form https://docs.google.com/forms/d/e/1FAIpQLSfZBSUp1bwOc_OimqcS6... 10) Who generated the random allocation sequence, who enrolled participants, and who assigned participants to interventions 11a) If done, who was blinded after assignment to interventions (for example, participants, care providers, those assessing outcomes) and how NPT: Whether or not administering co-interventions were blinded to group assignment subitem not at all important 1 2 3 4 5 essential Does your paper address CONSORT subitem 10? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No. randomization was done using the Qualtrics randomizer function 11a-i) Specify who was blinded, and who wasn't Specify who was blinded, and who wasn't. Usually, in web-based trials it is not possible to blind the participants [1, 3] (this should be clearly acknowledged), but it may be possible to blind outcome assessors, those doing data analysis or those administering co-interventions (if any).

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Does your paper address subitem 11a-i? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study Not relevant to our study.
CONSORT-EHEALTH (V 1.6.1) -Submission/Publication Form https://docs.google.com/forms/d/e/1FAIpQLSfZBSUp1bwOc_OimqcS6... 11a-ii) Discuss e.g., whether participants knew which intervention was the "intervention of interest" and which one was the "comparator" Informed consent procedures (4a-ii) can create biases and certain expectations -discuss e.g., whether participants knew which intervention was the "intervention of interest" and which one was the "comparator".

Clear selection
Does your paper address subitem 11a-ii?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study no. Subjects saw two PSA and responded to both. We did not ask them to report whether they interpreted one intervention as a control or intervention Does your paper address CONSORT subitem 11b? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study Yes. The full PSA used are in the appendix

12a-i) Imputation techniques to deal with attrition / missing values
Imputation techniques to deal with attrition / missing values: Not all participants will use the intervention/comparator as intended and attrition is typically high in ehealth trials. Specify how participants who did not use the application or dropped out from the trial were treated in the statistical analysis (a complete case analysis is strongly discouraged, and simple imputation techniques such as LOCF may also be problematic [4]).

Clear selection
Does your paper address subitem 12a-i? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study Does your paper address CONSORT subitem 12b? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No. We did not have any subgroup analyses

Clear selection
Does your paper address subitem X26-i?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study yes. "The study was reviewed by the Indiana University Institutional Review Board (IRB) as protocol #2004499544 and was determined to be an exempt study. " CONSORT-EHEALTH (V 1.6.1) -Submission/Publication Form https://docs.google.com/forms/d/e/1FAIpQLSfZBSUp1bwOc_OimqcS6...

x26-ii) Outline informed consent procedures
Outline informed consent procedures e.g., if consent was obtained offline or online (how? Checkbox, etc.?), and what information was provided (see 4a-ii). See [6] for some items to be included in informed consent documents.

Clear selection
Does your paper address subitem X26-ii?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study yes. "The study began with the IRB approved study information and if participants consented to participate, then they proceeded to the study."

X26-iii) Safety and security procedures
Safety and security procedures, incl. privacy considerations, and any steps taken to reduce the likelihood or detection of harm (e.g., education and training, availability of a hotline)

Clear selection
Does your paper address subitem X26-iii?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study

RESULTS
13a) For each group, the numbers of participants who were randomly assigned, received intended treatment, and were analysed for the primary outcome NPT: The number of care providers or centers performing the intervention in each group and the number of patients treated by each care provider in each center 13b) For each group, losses and exclusions after randomisation, together with reasons Does your paper address CONSORT subitem 13a? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study yes. See table 1 in the paper.
Does your paper address CONSORT subitem 13b? (NOTE: Preferably, this is shown in a CONSORT flow diagram) * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No. Eight subjects failed the attention check and we did not examine which treatment group they received; they were removed prior to analyses 1 2 3 4 5 essential 14a) Dates defining the periods of recruitment and follow-up

13b-i) Attrition diagram
Strongly recommended: An attrition diagram (e.g., proportion of participants still logging in or using the intervention/comparator in each group plotted over time, similar to a survival curve) or other figures or tables demonstrating usage/dose/engagement.

Clear selection
Does your paper address subitem 13b-i?
Copy and paste relevant sections from the manuscript or cite the figure number if applicable (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study

No. Not relevant to our study
Does your paper address CONSORT subitem 14a? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study yes. "In July, 2020, " was the recruitment. There was no followup CONSORT-EHEALTH (V 1.6.1) -Submission/Publication Form https://docs.google.com/forms/d/e/1FAIpQLSfZBSUp1bwOc_OimqcS6... 14a-i) Indicate if critical "secular events" fell into the study period Indicate if critical "secular events" fell into the study period, e.g., significant changes in Internet resources available or "changes in computer hardware or Internet delivery resources"

Clear selection
Does your paper address subitem 14a-i?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study

No. it is not relevant to our study
Does your paper address CONSORT subitem 14b? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No. the trial was not ended or stopped CONSORT-EHEALTH (V 1.6.1) -Submission/Publication Form https://docs.google.com/forms/d/e/1FAIpQLSfZBSUp1bwOc_OimqcS6... Does your paper address CONSORT subitem 15? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No. We did not examine this

15-i) Report demographics associated with digital divide issues
In ehealth trials it is particularly important to report demographics associated with digital divide issues, such as age, education, gender, social-economic status, computer/Internet/ehealth literacy of the participants, if known.

Clear selection
Does your paper address subitem 15-i? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study We report demographics but not income because that would be intrusive. "About 49% of participants were female, and 82% were White, 8% Asian, 7% Black, and 3% other. 16-i) Report multiple "denominators" and provide definitions Report multiple "denominators" and provide definitions: Report N's (and effect sizes) "across a range of study participation [and use] thresholds" [1], e.g., N exposed, N consented, N used more than x times, N used more than y weeks, N participants "used" the intervention/comparator at specific pre-defined time points of interest (in absolute and relative numbers per group). Always clearly define "use" of the intervention.
Does your paper address subitem 16-i? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No. Not relevant to our study.

16-ii) Primary analysis should be intent-to-treat
Primary analysis should be intent-to-treat, secondary analyses could include comparing only "users", with the appropriate caveats that this is no longer a randomized sample (see 18-i).

Clear selection
Does your paper address subitem 16-ii?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No. We do not understand the meaning of "intent-to-treat" so it was not mentioned that we know of.
CONSORT-EHEALTH (V 1.6.1) -Submission/Publication Form https://docs.google.com/forms/d/e/1FAIpQLSfZBSUp1bwOc_OimqcS6... 17a) For each primary and secondary outcome, results for each group, and the estimated effect size and its precision (such as 95% confidence interval) subitem not at all important 1 2 3 4 5 essential Does your paper address CONSORT subitem 17a? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study yes. "The effects were meaningful in size, increasing compliance by almost 13 percentage points for the Christian-framed PSA (95% CI: 2.9 to 22.6) and almost 7 percentage points for the economy-framed PSA (95% CI: 1.5 to 12.1) compared to the control, non-identity-framed PSA. The average effect sizes (Cohen's d) for the Christian-framed and economy-framed PSAs are 0.30 and 0.24, respectively, which are between small and medium. "

17a-i) Presentation of process outcomes such as metrics of use and intensity of use
In addition to primary/secondary (clinical) outcomes, the presentation of process outcomes such as metrics of use and intensity of use (dose, exposure) and their operational definitions is critical. This does not only refer to metrics of attrition (13-b) (often a binary variable), but also to more continuous exposure metrics such as "average session length". These must be accompanied by a technical description how a metric like a "session" is defined (e.g., timeout after idle time) [1] (report under item 6a).

Clear selection
Does your paper address subitem 17a-i?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No, this is not relevant to our study. Does your paper address CONSORT subitem 17b? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No, this is not relevant to our study.
Does your paper address CONSORT subitem 18? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No, this is not relevant to our study.

18-i) Subgroup analysis of comparing only users
A subgroup analysis of comparing only users is not uncommon in ehealth trials, but if done, it must be stressed that this is a self-selected sample and no longer an unbiased sample from a randomized trial (see 16-iii).

19) All important harms or unintended effects in each group
(for specific guidance see CONSORT for harms) subitem not at all important 1 2 3 4 5 essential Does your paper address subitem 18-i?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No, this is not relevant to our study.

Does your paper address CONSORT subitem 19? *
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No, this is not relevant to our study.

19-i) Include privacy breaches, technical problems
Include privacy breaches, technical problems. This does not only include physical "harm" to participants, but also incidents such as perceived or real privacy breaches [1], technical problems, and other unexpected/unintended incidents. "Unintended effects" also includes unintended positive effects [2].

Clear selection
CONSORT-EHEALTH (V 1.6.1) -Submission/Publication Form https://docs.google.com/forms/d/e/1FAIpQLSfZBSUp1bwOc_OimqcS6... NPT: In addition, take into account the choice of the comparator, lack of or partial blinding, and unequal expertise of care providers or centers in each group Does your paper address subitem 19-i?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No, this is not relevant to our study. We did not collect an personally identifying information.

19-ii) Include qualitative feedback from participants or observations from staff/researchers
Include qualitative feedback from participants or observations from staff/researchers, if available, on strengths and shortcomings of the application, especially if they point to unintended/unexpected effects or uses. This includes (if available) reasons for why people did or did not use the application as intended by the developers.

Clear selection
Does your paper address subitem 19-ii?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No, this is not relevant to our study. We did not collect this CONSORT-EHEALTH (V 1.6.1) -Submission/Publication Form https://docs.google.com/forms/d/e/1FAIpQLSfZBSUp1bwOc_OimqcS6... Restate study questions and summarize the answers suggested by the data, starting with primary outcomes and process outcomes (use).
Does your paper address subitem 22-i? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study Yes. "Our research shows that changing PSAs to leverage social and personal identities can promote increased compliance with public health guidelines for individuals who hold those identities. The Christian-framed PSA increased compliance by about 12.74 points (out of 100) when viewed by those with a Christian identity, and the economy-framed PSA increased compliance by about 6.77 points when viewed by those with an economy identity. One might conclude that the Christian framing is more powerful, but this only applies for people who hold that identity. Thus, we believe that it is better to compare the two different identityframed PSAs to their own controls, not to each other, as the differences in the coefficients between the two identity-aligned PSAs may be due to a variety of subject-level factors that influence their different identities. For example, those with a Christian identity were slightly less likely to comply (p=.012) with any PSA, possibly because those with conservative beliefs are less likely to believe that COVID-19 is a real threat [1,14]. "

22-ii) Highlight unanswered new questions, suggest future research
Highlight unanswered new questions, suggest future research.

Clear selection
CONSORT-EHEALTH (V 1.6.1) -Submission/Publication Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study yes. "We examined one social identity (Christian) and one personal identity (economicallymotivated) linked to noncompliance [36][37][38]. There are many other identities that may also be able to be leveraged to increase the effectiveness of PSAs. By reminding people of a role identity as a parent or grandchild, leveraging social group identities such as sports team loyalties, or by appealing to their self-identity as caring individuals, there are many opportunities to use identities to help persuade people to follow public health guidelines.
Our use of two identities shows that this method can be successful, but which other identities may also be used? Future research may also look into why some identities may be effective when used to increase compliance while others may not be effective. Is compliance affected more by the relationship of the identity to the target behavior or by the relationship of the identity to the individual, or are both equally important? While we control for trust toward the source of the PSA, an interesting question may be what the mediating influence of variables would be (e.g., perceived similarity to the identity used in the PSA). While we did not assess perceived similarity, we did control for the strength of identity. Now that our research suggests that identity-framed PSAs can be used to influence compliance, more research is needed to investigate the potential mediating and moderating variables that could strengthen or weaken the effectiveness of identity-framed PSAs. For example, our identity-framed PSA changed only one short sentence; would adding more identity-related framing increase its effectiveness, or is it sufficient to simply invoke the identity as in our PSAs? Likewise, is the source of the message a critical factor, or is the message more important than the source? This study has the usual limitations of cross-sectional randomly controlled experiments. We studied self-reported perceptions at one point in time, not actual behavior over several periods of time. Our participants were those who chose to participate in a research study, and thus may differ from individuals who choose not to participate in research studies. " CONSORT-EHEALTH (V 1.6.1) -Submission/Publication Form https://docs.google.com/forms/d/e/1FAIpQLSfZBSUp1bwOc_OimqcS6...

20-i) Typical limitations in ehealth trials
Typical limitations in ehealth trials: Participants in ehealth trials are rarely blinded. Ehealth trials often look at a multiplicity of outcomes, increasing risk for a Type I error. Discuss biases due to non-use of the intervention/usability issues, biases through informed consent procedures, unexpected events.

Clear selection
Does your paper address subitem 20-i? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study yes. "This study has the usual limitations of cross-sectional randomly controlled experiments. We studied self-reported perceptions at one point in time, not actual behavior over several periods of time. Our participants were those who chose to participate in a research study, and thus may differ from individuals who choose not to participate in research studies."

21-i) Generalizability to other populations
Generalizability to other populations: In particular, discuss generalizability to a general Internet population, outside of a RCT setting, and general patient population, including applicability of the study results for other organizations

OTHER INFORMATION
Does your paper address subitem 21-i?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study yes. "This study has the usual limitations of cross-sectional randomly controlled experiments. We studied self-reported perceptions at one point in time, not actual behavior over several periods of time. Our participants were those who chose to participate in a research study, and thus may differ from individuals who choose not to participate in research studies."

21-ii) Discuss if there were elements in the RCT that would be different in a routine application setting
Discuss if there were elements in the RCT that would be different in a routine application setting (e.g., prompts/reminders, more human involvement, training sessions or other co-interventions) and what impact the omission of these elements could have on use, adoption, or outcomes if the intervention is applied outside of a RCT setting.

Clear selection
Does your paper address subitem 21-ii?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study 23) Registration number and name of trial registry 24) Where the full trial protocol can be accessed, if available 25) Sources of funding and other support (such as supply of drugs), role of funders Does your paper address CONSORT subitem 23? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study Yes. " ISRCTN 22331899; https://www.isrctn.com/ISRCTN22331899 (retrospectively registered)" Does your paper address CONSORT subitem 24? * Cite a Multimedia Appendix, other reference, or copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study Yes. this is provided in Figure 1 and in the multi-media appendix.
Does your paper address CONSORT subitem 25? * Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No. The study had no funding.

X27) Conflicts of Interest (not a CONSORT item)
subitem not at all important 1 2 3 4 5 essential About the CONSORT EHEALTH checklist yes, major changes yes, minor changes no X27-i) State the relation of the study team towards the system being evaluated In addition to the usual declaration of interests (financial or otherwise), also state the relation of the study team towards the system being evaluated, i.e., state if the authors/evaluators are distinct from or identical with the developers/sponsors of the intervention.

Clear selection
Does your paper address subitem X27-i?
Copy and paste relevant sections from the manuscript (include quotes in quotation marks "like this" to indicate direct quotes from your manuscript), or elaborate on this item by providing additional information not in the ms, or briefly explain why the item is not applicable/relevant for your study No. This is not relevant to our study.