Accurate calculations of out-of-pocket costs for mental healthcare consultations.

What is known about the topic? When assessing real growth in costs, it is important to adjust for inflation through indexation to the Consumer Price Index (CPI). The change in prices or costs over time can be calculated in constant currency amounts by adjusting by a ratio of the CPI in the year of interest to the CPI in the baseline year. What does this paper add? Rosenberg et al. (2022) did not calculate out-of-pocket costs in constant currency, which does not give an accurate estimation of costs adjusted for inflation. What are the implications for practitioners? We calculated examples to illustrate the impact of such adjustments, which substantially impact the results of the study.