Abstract
Background: Behavioral intervention effectiveness in randomized controlled trials requires fidelity to the protocol. Fidelity assessment tools tailored to the intervention may strengthen intervention research.
Objective: The aim of this study was to describe the assessment of fidelity to the structured intervention protocol in an examination of a nurse-delivered telephone intervention designed to improve medication adherence.
Methods: Fidelity assessment included random selection and review of approximately 10% of the audiorecorded intervention sessions, stratified by interventionist and intervention session. Audiotapes were reviewed along with field notes for percentage of agreement, addressing whether key components were covered during the sessions. Visual analog scales were used to provide summary scores (0 = low to 5 = high) of interaction characteristics of the interventionists and participants with respect to engagement, demeanor, listening skills, attentiveness, and openness.
Results: Four nurse interventionists delivered 871 structured intervention sessions to 113 participants. Three trained graduate student researchers assessed 131 intervention sessions. The mean percentage of agreement was 92.0% (+/-10.5%), meeting the criteria of 90% congruence with the intervention protocol. The mean interventionist interaction summary score was 4.5 +/- 0.4, and the mean participant interaction summary score was 4.5 +/- 0.4.
Discussion: Overall, the interventionists successfully delivered the structured intervention content, with some variability in both the percentage of agreement and quality of interaction scores. Ongoing assessment aids in ensuring fidelity to study protocol and having reliable study results.