Analytical approach:
This patient level economic evaluation was based on one trial. The time horizon was almost two years and the authors did not report the study perspective.
Effectiveness data:
The effectiveness data were from one randomised controlled trial. From an initial sample of 555 patients, 438 were randomly assigned, with 172 allocated to a short wait and 266 allocated to a usual care. The key inclusion criteria were the need for a primary total knee replacement due to osteoarthritis of the knee joint. Patients were followed up at one year after surgery. Double-blinding was not possible, due to ethical reasons. The main clinical effectiveness estimates were the days waiting for surgery; and knee pain and function.
Monetary benefit and utility valuations:
Health-related quality of life (HRQoL) was measured using the generic 15-dimension (15D) questionnaire. The disease-specific, self-reported, modified Knee Society clinical rating system, Knee Score (KS) was used to measure knee pain and physical function.
Measure of benefit:
The primary measure of benefit was quality-adjusted life-years. Other benefit measures were the pain and function scores.
Cost data:
The main cost category was the cost of medication. The price per tablet was obtained from Pharmacy data. The costs of medication during the waiting period were calculated as a product of the weeks spent on the waiting list and the medication costs per week. All costs were reported in Euros (EUR).
Analysis of uncertainty:
The 95% confidence intervals were generated for the cost and benefit estimates.