An update on evidence of clinical pharmacy services' impact on health-related quality of life

OBJECTIVE: To describe and critique recent studies of clinical pharmacy services that have evaluated impact on health-related quality of life (HRQL) and to determine whether studies that lacked a control group were more likely to report a statistically significant impact on HRQL. DATA SOURCES: MEDLINE, EMBASE and International Pharmaceutical Abstracts were searched (March 1999-December 2004) using terms for HRQL and clinical pharmacy services. STUDY SELECTION AND DATA EXTRACTION: All original research articles in English identified from the data sources were examined. Abstracts were screened by 2 reviewers, and studies were included if a clinical pharmacy service was evaluated and pre-/post HRQL outcomes were reported. DATA SYNTHESIS: Of 1152 citations identified by the literature search, 36 articles met the inclusion criteria. Twenty-two studies had a condition-specific focus. Fifteen studies incorporated a generic HRQL measure (primarily the short-form-36 items), 13 studies used a condition-specific measure, and 8 studies included both. Significant impact on one or more domains of HRQL was predominantly demonstrated in interventions relating to asthma, hypertension, and chronic heart failure. Statistically significant change in HRQL was reported in 8 of 21 studies that used a randomized controlled design (38%), in 2 of 5 studies with a nonrandomized design with control group (40%), and in 6 of 8 studies without a control group (75%; chi(2) 2.00; p = 0.16). CONCLUSIONS: Since 1999, the number of published studies of clinical pharmacy services that evaluated HRQL as an endpoint has more than tripled. Study designs have improved in terms of longer length of follow-up, and a wider breadth of clinical services has been evaluated. Certain pharmacy services, such as asthma management, appear to offer the most convincing evidence for the value of clinical pharmacy services in terms of measurable short-term HRQL benefit.