Purpose-To compare the test-retest reliability, convergent validity, and overall feasibility/ usability of activity-based (AB) and time-based (TB) approaches for obtaining self-reported moderate-to-vigorous physical activity (MVPA) from adolescents.Methods-Adolescents (206 females and 114 males) completed two 3-d physical activity recalls using the AB and TB surveys, which contained identical lists of physical activities. The participants wore an MTI Actigraph ® accelerometer for the same period.Results-The TB instrument took about 3 min longer to complete (P = 0.022). Overall 2-d testretest correlations for MVPA were similar for the two surveys (r = 0.676 and 0.667), but the girls had higher reliability on the AB survey than the boys (girls: r = 0.713; boys: r = 0.568). The overall 3-d correlations for MVPA surveys and Actigraph counts varied by gender (girls: AB = 0.265 vs TB = 0.314; boys: AB = 0.340 vs TB = 0.277). Correlations for vigorous physical activity and Actigraph counts were higher for the AB than for the TB (r = 0.281 vs 0.162). As the interval between completing the surveys and the days being recalled increased, reliability and validity were lower, especially for the AB survey.Conclusion-For both genders, either approach is acceptable for obtaining MVPA information on a single day, but the TB approach appears to be slightly favored over the AB approach for obtaining multiple days of MVPA. A 3-d recall period appears to be too long for accurate recall of MVPA Address for Correspondence: Robert McMurray, Dept of Exercise and Sport Science, CB#8700, Fetzer Gym, University of North Carolina, Chapel Hill NC 27599-8700; Email: exphys@email.unc.edu. A complete list of activities used for the survey instruments, as well as the instruments and their instructions, can be obtained by contacting the primary author, Robert G. McMurray. NIH Public Access Author ManuscriptMed Sci Sports Exerc. Author manuscript; available in PMC 2008 June 8. Published in final edited form as:Med Sci Sports Exerc. 2004 December ; 36(12): 2135-2143. NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author Manuscript information from either instrument. For both genders, the surveys overestimated activity levels; thus, self-reports should be supplemented with objective data. Keywords ACCELEROMETERS; RELIABILITY; VALIDITY; YOUTH; EXERCISEThere are a number of self-report questionnaires used to obtain information on physical activity patterns in adolescents. Some of these focus on habitual activity (6,8,12,24), and others examine the previous 1-7 d of activity (20,21,22,25,27). Surveys that examine daily physical activity patterns have used various cues to assist respondents in completing the forms. One approach is a time-based (TB) recall strategy. The TB approach, used by the Previous Day Physical Activity Recall (PDPAR) (25,29) and 3-Day Physical Activity Recall (3DPAR) (18), requires the respondent to report physical activity performed during each of the previous 3 d, beginning with the most recent day and working ba...

Locational data, logged on portable GPS units and matched with accelerometer data, was used to examine associations of the built environment with physical activity and sedentary behaviors of adolescent females. In a sample of 293 adolescent females ages 15 to 18 years old in Minneapolis and San Diego, the built environment around each GPS point and its corresponding sedentary, light, and moderate-to-vigorous intensity physical activity were examined using random intercept multinomial logistic regression models. The odds of higher physical activity intensity (3-level outcome: sedentary, light, MVPA) were higher in places with parks, schools, and high population density, during weekdays, and lower in places with more roads and food outlets. Understanding the places where physical activity and sedentary behaviors occur appears to be a promising strategy to clarify relationships and inform policy aimed at increasing physical activity and reducing sedentary behaviors.

Formative research uses qualitative and quantitative methods to provide information for researchers to plan intervention programs. Gaps in the formative research literature include how to define goals, implementation plans, and research questions; select methods; analyze data; and develop interventions. The National Heart, Lung, and Blood Institute funded the Trial of Activity for Adolescent Girls (TAAG), a randomized, multicenter field trial, to reduce the decline in physical activity in adolescent girls. The goals of the TAAG formative research are to (a) describe study communities and schools, (b) help design the trial's interventions, (c) develop effective recruitment and retention strategies, and (d) design evaluation instruments. To meet these goals, a variety of methods, including telephone interviews, surveys and checklists, semistructured interviews, and focus group discussions, are employed. The purpose, method of development, and analyses are explained for each method.

Process evaluation is a component of intervention research that evaluates whether interventions are delivered and received as intended. Here, we describe the process evaluation results for the Trial of Activity for Adolescent Girls (TAAG) intervention. The intervention consisted of four synergistic components designed to provide supportive school- and community-linked environments to prevent the decline in physical activity in adolescent girls. Process evaluation results indicate that the intervention components were delivered from intervention staff to teachers with high fidelity (84–97%) to the protocol and with lower fidelity (range: 18–93%) from teachers to students. Physical activity programs for girls, a unique feature of the TAAG intervention, increased from a mean of 10 programs per school to a mean of 16 and 15 in years 1 and 2, respectively, in intervention schools, with no change in control schools. These findings suggest that a multicomponent school- and community-based physical activity intervention can be delivered with fidelity and result in a middle school environment that supports physical activity for girls.

Introduction Most evidence-based interventions to improve fruit and vegetable (FV) consumption target individual behaviors and family systems; however, these changes are difficult to sustain without environmental support. This paper describes an innovative social and structural food store-based intervention to increase availability and accessibility of FVs in tiendas (small-to medium-sized Latino food stores) and purchasing and consumption of FVs among tienda customers. Methods Using a cluster randomized controlled trial with 16 tiendas pair-matched and randomized to an intervention or wait-list control condition, this study will evaluate a 2-month intervention directed at tiendas, managers, and employees followed by a 4-month customer-directed food marketing campaign. The intervention involves social (e.g., employee trainings) and structural (e.g., infrastructure) environmental changes. Three hundred sixty-nine customers (approximately 23 per tienda) serve on an evaluation cohort and complete assessments (interviews and measurements of weight) at 3 time points: baseline, 6-months post-baseline, and 12-months post-baseline. The primary study outcome is customer-reported daily consumption of FVs. Manager interviews and monthly tienda audits and collection of sales data will provide evidence of tienda-level intervention effects, our secondary outcomes. Process evaluation methods assess dose delivered, dose received, and fidelity. Results Recruitment of tiendas, managers, employees, and customers is complete. Demographic data shows that 30% of the customers are males, thus providing a unique opportunity to examine the effects of a tienda-based intervention on Latino men. Conclusions Determining whether a tienda-based intervention can improve customers’ FV purchasing and consumption will provide key evidence for how to create healthier consumer food environments.