School of Pharmacy, Faculty of Medicine and Health, University of Sydney, Australia.
Royal Prince Alfred Hospital, Sydney, Australia.
Am J Health Syst Pharm. 2021 Aug 30;78(17):1559-1567. doi: 10.1093/ajhp/zxab211.
Cost-avoidance studies of pharmacist interventions are common and often the first type of study conducted by investigators to quantify the economic impact of clinical pharmacy services. The purpose of this primer is to provide guidance for conducting cost-avoidance studies pertaining to clinical pharmacy practice.
Cost-avoidance studies represent a paradigm conceptually different from traditional pharmacoeconomic analysis. A cost-avoidance study reports on cost savings from a given intervention, where the savings is estimated based on a counterfactual scenario. Investigators need to determine what specifically would have happened to the patient if the intervention did not occur. This assessment can be fundamentally flawed, depending on underlying assumptions regarding the pharmacists' action and the patient trajectory. It requires careful identification of the potential consequence of nonaction, as well as probability and cost assessment. Given the uncertainty of assumptions, sensitivity analyses should be performed. A step-by-step methodology, formula for calculations, and best practice guidance is provided.
Cost-avoidance studies focused on pharmacist interventions should be considered low-level evidence. These studies are acceptable to provide pilot data for the planning of future clinical trials. The guidance provided in this article should be followed to improve the quality and validity of such investigations.
药师干预的成本避免研究很常见，通常是调查人员进行的第一种类型的研究，用于量化临床药学服务的经济影响。本指南旨在为临床药学实践相关的成本避免研究提供指导。
成本避免研究代表了一种与传统药物经济学分析在概念上不同的范例。成本避免研究报告了给定干预措施的成本节约，其中节约是基于反事实情景估计的。调查人员需要确定如果干预措施不发生，患者会发生什么具体情况。这种评估可能存在根本缺陷，具体取决于对药剂师的行动和患者轨迹的基本假设。这需要仔细确定不采取行动的潜在后果，以及概率和成本评估。鉴于假设的不确定性，应进行敏感性分析。提供了逐步的方法、计算公式和最佳实践指南。
应将侧重于药师干预的成本避免研究视为低水平证据。这些研究可以接受，为未来临床试验的规划提供试点数据。应遵循本文提供的指南，以提高此类研究的质量和有效性。
