Background: Exercise training (ET) is a promising rehabilitation approach for long-term negative consequences of traumatic brain injury (TBI). However, little is known regarding overall rates of attrition, adherence, and compliance to ET in TBI.
Objective: The purpose of this systematic review was to estimate average attrition, adherence, and compliance rates in ET studies in persons with TBI.
Methods: Databases were searched from inception to April 15, 2024. Two authors independently extracted data related to attrition, adherence, compliance, and possible moderators identified a priori.
Results: The average rate of attrition from 45 studies was 14.4%, although the majority of studies had small sample sizes (i.e. n < 42). Based on hierarchical linear regression, the most influential predictors of attrition were sample size and study design. A minority of studies reported adherence (44.4%) or compliance (22.2%) but those that did reported good average adherence (85.1%) and compliance (77.7%). These studies support the ability of persons with TBI to complete an ET intervention as prescribed.
Conclusions: Researchers can use this information to ensure adequate power to detect a true effect of ET in persons with TBI. Researchers conducting ET studies in persons with TBI should clearly and thoroughly report data on attrition, adherence, and compliance.
Keywords: Traumatic brain injury (TBI); adherence; attrition; compliance; exercise training; systematic review.