Objective measurement of physical activity with accelerometers is a challenging task in community-based intervention research. Challenges include distribution of and orientation to monitors, nonwear, incorrect placement, and loss of equipment. Data collection among participants from disadvantaged populations may be further hindered by factors such as transportation challenges, competing responsibilities, and cultural considerations.
Research staff distributed accelerometers and provided an orientation that was tailored to the population group. General adherence strategies such as follow-up calls, daily diaries, verbal and written instructions, and incentives were accompanied by population-specific strategies such as assisting with transportation, reducing obstacles to wearing the accelerometer, tailoring the message to the participant population, and creating a nonjudgmental environment.
Sixty women asked to wear the Actigraph GT1M returned the accelerometer, and 57 of them provided sufficient data for analysis (at least 10 hours a day for a minimum of 4 days) resulting in 95% adherence to the protocol. Participants wore the accelerometers for an average of 5.98 days and 13.15 hours per day.
The high accelerometer monitoring adherence among this group of economically disadvantaged women demonstrates that collection of high-quality, objective physical activity data from disadvantaged populations in field-based research is possible.
Sharpe, Strong, Hopkins-Campbell, and Butel are with the Prevention Research Center, University of South Carolina, Columbia, SC. Wilcox is with the Dept of Exercise Science, University of South Carolina, Columbia, SC. Rooney is with the Dept of Health Promotion, Education, and Behavior, University of South Carolina, Columbia, SC. Ainsworth is with the Exercise and Wellness Program, School of Nutrition and Health Promotion, Arizona State University, Phoenix, AZ. Parra-Medina is with the Institute for Health Promotion Research, Dept of Epidemiology and Biostatistics, University of Texas Health Science Center San Antonio, San Antonio, TX.