‘Compliance’ versus ‘adherence’ in sport injury prevention: why definition matters

For sport injury prevention efforts to be successful, athletes must adopt and continue to use preventive measures.1 To this end, researchers have conceptualised intervention uptake as both a modifying factor in efficacy trials,2 and as an outcome in effectiveness and implementation studies.3 While this has advanced our understanding of effective intervention designs, dose–response relationships, and barriers to programme use, the definition of ‘uptake’ has been inconsistent. Researchers often use ‘compliance’ and ‘adherence’ interchangeably, overlooking important differences in these constructs.4 We propose that efficacy trials require ‘compliance’, but effectiveness studies do not; instead, these should measure and interpret ‘adherence’ in real-life contexts. This distinction is an important first step for developing a framework to guide appropriate selection of outcome measures, measurement tools and analysis strategies to answer specific research questions. ‘Compliance’ refers to the act of an individual conforming to professional recommendations with regard to prescribed dosage, timing and frequency of an intervention.5 This requires the measurement of behaviour relative to a fixed standard, …