The impact of pharmacist interventions on health-related quality of life.

OBJECTIVE

To describe and evaluate pharmacy practice-based studies that include health-related quality of life (HRQL) as an outcome measure in assessments of pharmacist interventions and to recommend approaches for incorporating HRQL as a patient outcome in pharmacy practice-based intervention studies.

METHODS

Citations were identified in MEDLINE, Healthstar, EMBASE, and International Pharmaceutical Abstracts from January 1988 to February 1999 using terms for health-related quality of life and pharmacist interventions. Abstracts were screened by two reviewers and articles that reported a pharmacist intervention performed with HRQL as an outcome measure were included.

RESULTS

Of 689 citations identified by the literature search terms, 11 met the inclusion criteria. Nine studies contained a disease-specific focus. The SF-36, or its variations, was the only generic instrument used, and seven studies described using a disease-specific instrument. Pharmacist interventions inconsistently demonstrated positive effects on patient HRQL.

DISCUSSION

Possible reasons for not detecting significant differences in HRQL include length of study period, insufficient sample size and power, selection bias, labeling effects, the type of measure applied, and lack of actual influence of pharmaceutical services on HRQL. Strategies to strengthen the design and methodologic approach, such as the reporting of effect size, are recommended.

CONCLUSIONS

In order to demonstrate the positive effect of pharmaceutical services on patient health, pharmacy practice researchers should continue incorporating HRQL outcome measures, complemented by clinical, economic, and other humanistic outcome indicators.