Pharmacist Interventions and Drug‐Related Problems Classification Systems in the Inpatient Setting: A Systematic Review of Psychometric Properties

BACKGROUND: Pharmacist intervention (PI) is an important strategy for reducing drug-related problems (DRP; events or circumstances related to drug therapy that actually or potentially interfere with desired health outcomes) and improving efficiency, quality, and clinical outcomes, thereby avoiding unnecessary health care costs. This systematic review aims to identify and analyze studies that have validated PI and/or DRP classification systems within inpatient hospital settings, and to assess the validity and quality of the methodological procedures adopted in these systems. METHODS: This research followed the recommendations of the Cochrane Handbook for Systematic Reviews of Interventions. We searched MEDLINE, Embase, LILACS, Web of Science, Scopus, and the gray literature databases without restrictions on publication date or language. Two authors independently carried out study selection, data extraction, quality assessment, and analysis. A narrative synthesis was conducted, and the results were tabulated and synthesized descriptively in tables and in the text. RESULTS: Seventeen articles were included, in which 14 distinct classification systems for PI and/or DRP were identified. Most studies (13/17) were conducted in Europe, did not conceptualize the construct of interest (12/17), failed to disclose the undertaking of a literature review to support the generation of items for the classification system (13/17), and did not assess the content validity evidence (13/17). Also, the majority of studies (15/17) demonstrated the reliability of the classification instrument, but did not report whether the sample used was representative of the population, information on controlling confounding variables, or on evaluator blinding. CONCLUSION: Most instruments demonstrated acceptable reliability. However, few studies assessed sources of validity evidence, often with methodological limitations. Further studies employing rigorous methods for assessing validity evidence are needed to develop an instrument that is both valid and reliable for use in hospital pharmacy clinical practice.