Validation of Web-Based Physical Activity Measurement Systems Using Doubly Labeled Water
نویسندگان
چکیده
BACKGROUND Online or Web-based measurement systems have been proposed as convenient methods for collecting physical activity data. We developed two Web-based physical activity systems-the 24-hour Physical Activity Record Web (24hPAR WEB) and 7 days Recall Web (7daysRecall WEB). OBJECTIVE To examine the validity of two Web-based physical activity measurement systems using the doubly labeled water (DLW) method. METHODS We assessed the validity of the 24hPAR WEB and 7daysRecall WEB in 20 individuals, aged 25 to 61 years. The order of email distribution and subsequent completion of the two Web-based measurements systems was randomized. Each measurement tool was used for a week. The participants' activity energy expenditure (AEE) and total energy expenditure (TEE) were assessed over each week using the DLW method and compared with the respective energy expenditures estimated using the Web-based systems. RESULTS The mean AEE was 3.90 (SD 1.43) MJ estimated using the 24hPAR WEB and 3.67 (SD 1.48) MJ measured by the DLW method. The Pearson correlation for AEE between the two methods was r = .679 (P < .001). The Bland-Altman 95% limits of agreement ranged from -2.10 to 2.57 MJ between the two methods. The Pearson correlation for TEE between the two methods was r = .874 (P < .001). The mean AEE was 4.29 (SD 1.94) MJ using the 7daysRecall WEB and 3.80 (SD 1.36) MJ by the DLW method. The Pearson correlation for AEE between the two methods was r = .144 (P = .54). The Bland-Altman 95% limits of agreement ranged from -3.83 to 4.81 MJ between the two methods. The Pearson correlation for TEE between the two methods was r = .590 (P = .006). The average input times using terminal devices were 8 minutes and 10 seconds for the 24hPAR WEB and 6 minutes and 38 seconds for the 7daysRecall WEB. CONCLUSIONS Both Web-based systems were found to be effective methods for collecting physical activity data and are appropriate for use in epidemiological studies. Because the measurement accuracy of the 24hPAR WEB was moderate to high, it could be suitable for evaluating the effect of interventions on individuals as well as for examining physical activity behavior.
منابع مشابه
Practice of Epidemiology Validation of a Food Frequency Questionnaire by Direct Measurement of Habitual ad Libitum Food Intake
Food frequency questionnaires are commonly used to assess habitual food intake. Although food frequency questionnaires are known to produce measurement error, the amount of error and effectiveness of correction methods are poorly understood. Twelve men from the Baltimore, MD/Washington, DC, area consumed an ad libitum diet for 16 weeks during the spring of 2001. At the end of the study period, ...
متن کاملValidation of a food frequency questionnaire by direct measurement of habitual ad libitum food intake.
Food frequency questionnaires are commonly used to assess habitual food intake. Although food frequency questionnaires are known to produce measurement error, the amount of error and effectiveness of correction methods are poorly understood. Twelve men from the Baltimore, MD/Washington, DC, area consumed an ad libitum diet for 16 weeks during the spring of 2001. At the end of the study period, ...
متن کاملActive-Q: Validation of the Web-Based Physical Activity Questionnaire Using Doubly Labeled Water
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) l...
متن کاملApplication of the Doubiy Labeied Water Technique for Studying Total Energy Expenditure in Young Chiidren: A Review
The doubly labeled water tecbnique represents an unobtrusive and noninvasive means lo measure total daily energy expenditure in free-living human subjects who are unaware that energy expenditure is being measured. When combined with measurement of resting energy expenditure, the doubly labeled water technique can also be used to estimate energy expenditure related to physical activity. The rela...
متن کاملPractice of Epidemiology A Measurement Error Model for Physical Activity Level as Measured by a Questionnaire With Application to the 1999–2006 NHANES Questionnaire
Systematic investigations into the structure of measurement error of physical activity questionnaires are lacking. We propose a measurement error model for a physical activity questionnaire that uses physical activity level (the ratio of total energy expenditure to basal energy expenditure) to relate questionnaire-based reports of physical activity level to true physical activity levels. The 19...
متن کامل