Table 1.

Four approaches to studying adherence.

Approach	Type of adherence data expected
Analysis of dropout data	Comparison of adherent and nonadherent service-user data including demographic, symptom, cognitive or other data; baseline assessment of between group differences
Within studies analyses to establish relationship between adherence and various factors	Within study correlational, regression or other analysis of service-user specific factors or intervention specific factors that may impact on the level of adherence to intervention or technology
Poststudy questionnaire on participants’ experience	Questionnaire data; qualitative or quantitative feedback on satisfaction, acceptability of study or intervention with specific questions on usability, helpfulness, and continued use
Experimental manipulation of factors impacting adherence	Comparison of interventions or interfaces that are specifically designed to impact on adherence