Observational measures of implementer fidelity for a school-based preventive intervention: development, reliability, and validity.

Current measures of implementer fidelity often fail to adequately measure core constructs of adherence and competence, and their relationship to outcomes can be mixed. To address these limitations, we used observational methods to assess these constructs and their relationships to proximal outcomes in a randomized trial of a school-based preventive intervention (Rochester Resilience Project) designed to strengthen emotion self-regulation skills in first-third graders with elevated aggressive-disruptive behaviors. Within the intervention group (n = 203), a subsample (n = 76) of students was selected to reflect the overall sample. Implementers were 10 paraprofessionals. Videotaped observations of three lessons from year 1 of the intervention (14 lessons) were coded for each implementer-child dyad on adherence (content) and competence (quality). Using multilevel modeling, we examined how much of the variance in the fidelity measures was attributed to implementer and to the child within implementer. Both measures had large and significant variance accounted for by implementer (competence, 68 %; adherence, 41 %); child within implementer did not account for significant variance indicating that ratings reflected stable qualities of the implementer rather than the child. Raw adherence and competence scores shared 46 % of variance (r = .68). Controlling for baseline differences and age, the amount (adherence) and quality (competence) of program delivered predicted children's enhanced response to the intervention on both child and parent reports after 6 months, but not on teacher report of externalizing behavior. Our findings support the use of multiple observations for measuring fidelity and that adherence and competence are important components of fidelity which could be assessed by many programs using these methods.