Applying micro-costing methods to estimate the costs of pharmacy interventions: an illustration using multi-professional clinical medication reviews in care homes for older people.

Objectives: Economic methods are underutilised within pharmacy research resulting in a lack of quality evidence to support funding decisions for pharmacy interventions. The aim of this study is to illustrate the methods of micro-costing within the pharmacy context in order to raise awareness and use of this approach in pharmacy research.

Methods: Micro-costing methods are particularly useful where a new service or intervention is being evaluated and for which no previous estimates of the costs of providing the service exist. This paper describes the rationale for undertaking a micro-costing study before detailing and illustrating the process involved. The illustration relates to a recently completed trial of multi-professional medication reviews as an intervention provided in care homes. All costs are presented in UK£2012.

Key Findings: In general, costing methods involve three broad steps (identification, measurement and valuation); when using micro-costing, closer attention to detail is required within all three stages of this process. The mean (standard deviation; 95% confidence interval (CI) ) cost per resident of the multi-professional medication review intervention was £104.80 (50.91; 98.72 to 109.45), such that the overall cost of providing the intervention to all intervention home residents was £36,221.29 (95% CI, 32 810.81 to 39 631.77).

Conclusions: This study has demonstrated that micro-costing can be a useful method, not only for estimating the cost of a pharmacy intervention to feed into a pharmacy economic evaluation, but also as a source of information to help inform those designing pharmacy services about the potential time and costs involved in delivering such services.