Development and application of validation methods for community pharmacy

Abstract

The concept of validation, which is today an essential procedure in the area of chemical analysis, was applied to the area of pharmacy practice. The aim of this research study was to develop validation tools which can be used by community pharmacists to monitor the standards of services provided and to measure the impact of the intervention of the pharmacist in a community setting. The validation process is divided into two parts namely the internal validation study where measurement of standards is undertaken from within the profession and the external validation study where measurement of standards is carried out by consumers and by non-pharmacist members of the health-care team. In order to develop internal validation tools, background studies were carried out to identify professional services for which measurement instruments had to be developed. The background studies consisted of a baseline study and of a field observation study. In the baseline study, data on the services provided from community pharmacies were collected from private community pharmacies (n=184) through a personal visit to all private community pharmacies in Malta (n=189). The field observation study was carried out in 10 community pharmacies selected using stratified random sampling. The investigator visited each pharmacy and in total 1800 minutes of pharmacist time were observed. Using the data obtained in the field observation study the Quantitative Community Pharmacy Model was developed from which the internal validation tools to be established were elicited. Five internal validation tools were developed namely The Setting of the Community Pharmacy, Dispensing a Prescription, Responding to Symptoms, Communicating with the Patient and Equipment and Professional Services available in a Community Pharmacy. Local systems and established international guidelines were used to identify indicators of good pharmacy practice which in turn were used to develop the tools. Face and content validity of the internal validation tools were assessed by setting up a group of explicit judges with mixed expertise. Inter-observer reliability of the five internal validation tools was assessed. The five internal validation tools were applied by the investigator and another rater in the community pharmacies which were randomly selected for the field observation study. Factor analysis was carried out using Biomedical Data Package software version 7.0. Face and content validity of the five internal validation tools were found to be strong. The correlation coefficient for the overall score obtained by the two raters for each tool was high (rs >0.70) indicating consistency of scoring of the tools by different raters. Internal consistency was high (Cronbach's alpha >0.80) for the five internal validation tools. For the external validation process, two external validation tools were developed, namely the Consumer Services Tool directed at consumers and the Health Professionals Tool directed at non-pharmacist members of the health-care team. Face and content validity of the external validation tools were assessed using the same expert judges involved with the review of the five internal validation tools. The test-retest method was adopted to assess the reliability of the two external validation tools. The Biomedical Data Package Software version 7.0 was used to carry out factor analysis. Face and content validity of the two external validation tools were found to be strong. The correlation coefficient for the overall score for test 1 and 2 for each tool was high (rs >0.95) indicating reliability of the two tools. Internal consistency was found to be high (Cronbach's alpha >0.95) for both external validation tools. A standardised protocol for the implementation of the process of validation of community pharmacy was prepared. A pilot test was carried out in 50 community pharmacies selected using stratified random sampling. Areas where these pharmacies need to upgrade the professional services provided were identified. The study revealed that consumers had a good perception of the community pharmacist and that they are satisfied with the services provided while non-pharmacist members of the health-care team were aware of the need to improve professional services provided by the community pharmacist. This research project led to the development and to the psychometric evaluation of validation tools which can be used to monitor standards of professional services provided by the community pharmacist. The validation tools are intended to serve as benchmark procedures in different countries so that international harmonisation of instruments used to measure the effectiveness of the pharmacist in a community setting is achieved.