Characterization of published randomized controlled trials assessing clinical pharmacy services around the world

A critical analysis of the research on clinical pharmacy services with regards to study characteristics has not been undertaken since 1998. However, several meta-analyses have been conducted to demonstrate the impact of pharmacists' interventions in specific medical conditions. These meta-analyses present high heterogeneity in part because the interventions are poorly and inconsistently described in primary studies. The aim of this article is to present the characteristics of randomized control trials (RCTs) that assess clinical pharmacy services to identify areas of improvement in future pharmacy practice research studies. Different emphasis of research across geographic regions of the world were also examined. During these 40 years, 520 articles reporting 439 RCTs assessing clinical pharmacy services were published. Of the 439 studies, 77.7% (n = 341) were published in the year 2000 or thereafter, 41.46% (n = 182) were conducted in the US, 27.56% (n = 121) in Europe, and 30.98% (n = 136) in the rest of the world. Studies in pharmacy practice have improved in terms of design, with an increase in the number of published RCTs after 2000. However, the small sample size of RCTs is still an issue. After 2000, a significantly higher proportion of studies were conducted in community pharmacy, targeting specific medical conditions, and with a higher number of patients randomized to the intervention group. Conversely, a significantly smaller proportion of studies were conducted in the hospital and targeted a single recipient after 2000. Studies conducted in the US had significantly more intervention arms, focused mostly on a specific medical condition, and were performed in primary care. Different health care systems' organization and policies may influence clinical pharmacy services research across countries.