Development and testing of two implementation tools to measure components of professional pharmacy service fidelity

There is a need to evaluate both service process and implementation outcomes as professional services are being implemented into pharmacy practice. Fidelity is an implementation outcome, which may be used for service optimization, by associating service components to patient outcomes, as well as use in process evaluation. The objective of this study was to develop tools to measure components of fidelity, specifically, an adherence index (adherence of the service provider to the elements of the service) and a patient responsiveness scale for the professional pharmacy service, medication review with follow-up.

The procedure described by DeVellis was followed to develop the tools. An expert panel was used to create items and establish content validity. Primary data were collected from 190 service provider pharmacists from 128 pharmacies across 11 provinces of Spain using Spanish version tools as part of an ongoing implementation study (English translations appended to the online version of the article as supplementary material). An initial assessment of item functionality was performed using descriptive statistics and item discrimination for both tools. The patient responsiveness scale's internal consistency was confirmed by calculating Cronbach's alpha coefficient and inter-item correlations. In addition, for the patient responsiveness scale, the number of factors to retain was based on Kaiser criterion, parallel analysis and Cattell's scree test and the number of items was optimized as guided by iterative exploratory factor analysis (EFA).

Acceptability of both tools was high. An adherence index of 39 items was developed. After five EFA iterations, four items were removed, resulting in a reliable, 12-item, two-factor patient responsiveness scale, explaining 53.9% of total variance.

Two tools for measuring implementation fidelity, an adherence index and a patient responsiveness scale, have been developed and tested. Future assessment, in particular to establish criterion validity, is recommended.