Cost offset PT vs. TAU
The cost offset of a psychotherapeutic intervention PT vs. TAU (Cost offset PT vs. TAU) represents the difference in total costs after the intervention is provided compared to cost related to the provision of treatment as usual (TAU) (i.e. post- difference in healthcare cost related to PT vs. TAU).
In order to assess the costs and cost offsets, and to present a financial evaluation, we applied present-day financial costing standards to the data. Cost data were inflated and converted to 2015 US-$ purchasing power parities (PPP) to ensure comparability of the data [24].
If an included study did not report the cost year, the year in which the study was accepted for publication was used as a proxy. To further ensure comparability of the data, costs per patient were calculated if costs data related to groups or a population. Subsequently, if the time horizon chosen in the study was less or more than one year, costs were converted to one year costs.
Due to the variation in sample size, means weighted for sample size were calculated and reported when presenting the overall cost offset of PT and the overall cost offset of PT vs TAU of all the economic evaluations identified in this review, and where appropriate, compared using independent samples t test.