@Article{info:doi/10.2196/jmir.1974,
author="Bonn, Stephanie Erika
and Trolle Lagerros, Ylva
and Christensen, Sara Elisabeth
and M{\"o}ller, Elisabeth
and Wright, Antony
and Sj{\"o}lander, Arvid
and B{\"a}lter, Katarina",
title="Active-Q: Validation of the Web-Based Physical Activity Questionnaire Using Doubly Labeled Water",
journal="J Med Internet Res",
year="2012",
month="Feb",
day="15",
volume="14",
number="1",
pages="e29",
keywords="activity assessment; epidemiology; Internet; total energy expenditure",
abstract="Background: Increased use of the Internet provides new opportunities for collecting data in large studies. The aim of our new Web-based questionnaire, Active-Q, is to assess total physical activity and inactivity in adults. Active-Q assesses habitual activity during the past year via questions in four different domains: (1) daily occupation, (2) transportation to and from daily occupation, (3) leisure time activities, and (4) sporting activities. Objective: The objective of our study is to validate Active-Q's energy expenditure estimates using the doubly labeled water (DLW) method, and to assess the reproducibility of Active-Q by comparing the results of the questionnaire completed by the same group on two occasions. Methods: The validity and reproducibility of Active-Q were assessed in a group of 37 individuals, aged 20 to 65 years. Active-Q was distributed via email to the participants. The total energy expenditure of the participants was assessed using DLW for 11 consecutive days. Results: The median time to complete Active-Q was 6.1 minutes. The majority of participants (27/37, 73{\%}) reported that the questionnaire was ``easy'' or ``very easy'' to answer. On average, Active-Q overestimated the total daily energy expenditure by 440 kJ compared with the DLW. The Spearman correlation between the two methods was r = 0.52 (P < .001). The intraclass correlation coefficient for total energy expenditure between the results of Active-Q completed on two occasions was 0.83 (95{\%} CI 0.73-0.93). Conclusions: Active-Q is a valid and reproducible method of assessing total energy expenditure. It is also a user-friendly method and suitable for Web-based data collection in large epidemiological studies. ",
issn="1438-8871",
doi="10.2196/jmir.1974",
url="http://www.jmir.org/2012/1/e29/",
url="https://doi.org/10.2196/jmir.1974",
url="http://www.ncbi.nlm.nih.gov/pubmed/22356755"
}