Short CommunicationAccelerometer data treatment for adolescents: Fitting a piece of the puzzle

- We examine the impact of different accelerometer data inclusion criteria on participant retention.
- Fewer participants were included with more stringent accelerometer data inclusion criteria.
- Higher body fatness was associated with reduced odds of meeting more stringent criteria.
- Moderate-to-vigorous activity was associated with reduced odds of meeting more stringent criteria.

This study aimed to assess the differences in participant retention and associations between physical activity and key variables when a range of accelerometer data inclusion criteria are employed. Data were drawn from 204 adolescents of Pacific Island heritage (survey, body composition, 7-day accelerometry) and their parents (date of birth, socioeconomic status) between October 2014 and February 2016 in Auckland, New Zealand. Data wear time criteria for inclusion were as follows: A) > = 10 h/weekday or > = 8 h weekend day, > = 5 days (at least one weekend day); B) > = 10 h/weekday or > = 8 h weekend day, > = 4 days; C) > = 7 h/day, > = 3 days; D) > = 10 h/day, > = 1 day. Overall, 49%, 62%, 88%, and 96% of participants met the criteria, respectively. Adjusted odds of meeting each criterion were examined using a multivariable logistic regression model. Almost 50% of participants were excluded by the most stringent inclusion criteria. Increased body fat percentage and proportion of time in moderate-to-vigorous activity were associated with decreased odds of meeting Criterions A and B. This research contributes to a growing understanding of the impact of differing accelerometer reduction approaches to sample retention and bias in adolescent physical activity research.