Cost-effectiveness analysis of each strategy
The direct cost of the phone call strategy was €430.38, whereas the mail letter strategy was €222.6. If we include the switch path in this calculation, the cost of the phone call strategy amounts to €681.08 compared with €360.8 for the mail letter strategy.The cost per patient who attended the medical visit was €621.3 (2.5 QALY) in the phone call strategy and €611.8 (2.4 QALY) in the mail letter strategy, with an incremental cost-effectiveness ratio of €235/QALY. When the switch is included, the cost of the phone call strategy was €854.2 (1.9 QALY) and €650 (1.1 QALY), with an incremental cost-effectiveness ratio of €259/QALY. Figure Two-way sensitivity analysis.