618 MEP051 – Compliance to responding to weekly questionnaires and to adhering to an injury risk reduction programme during a randomized controlled trial in athletics

AbstractBackground Often, the proportion of athletes responding to weekly questionnaires is low and their low adherence to following a predefined intervention is problematic in randomized controlled trials exploring efficacy of injury prevention programme.Objective To investigate the potential differences between athletes' characteristics in time to 1) non-response to weekly questionnaire on injury and exposure data and 2) non-compliance with an intervention.Design Cohort study with 39-weeks follow-up.Setting Secondary analysis of data from PREVATHLE randomized controlled trial.Participants 840 female and male competitive athletics athletes.Intervention Unsupervised exercise-based injury prevention programme.Main Outcomes Measures We analyzed the association between athletes' baseline characteristics (intervention/control group, sex, age, explosive/endurance discipline, athletics and non-specific sport training, previous injuries) and the following outcomes: time to failing to (1) responding to a weekly questionnaire and (2) complete a prescribed intervention using univariate Cox proportional hazards regression models.Results Over the 39 weeks, eighty percent of athletes failed to complete all questionnaires (n=672), with female, younger, explosive-related discipline athletes, athletes in the intervention group and with higher non-specific sport training, failing faster. Nearly all athletes (n=446; 99.3%) in the intervention group failed to comply with the intervention. In the latter, no certain characteristics amongst the athletes were identified to fail faster than their athletic peers with other characteristics. Conclusions Strategies to improve athletes´ willingness to responding to weekly questionnaires and to complete the intervention as prescribed should take into consideration when designing randomized trials trails in a sports science context.