The base case considered the continuous abstinence rates during one year of the interventions for 50% of eligible patients, over 25 years. Compared with usual care, the incremental life-years were 210 with minimal counselling, 690 with intensive counselling, and 1,590 with pharmacotherapy. The QALYs were 280 with minimal counselling, 960 with intensive counselling, and 2,240 with pharmacotherapy.
The additional intervention costs (in millions) were EUR 6.8 with minimal counselling, EUR 15.6 with intensive counselling, and EUR 23.2 with pharmacotherapy. The savings in COPD costs (in millions) were EUR 2.0 with minimal counselling, EUR 7.6 with intensive counselling, and EUR 17.9 with pharmacotherapy.
Compared with usual care, the incremental cost per life-year gained was EUR 22,400 with minimal counselling, EUR 11,600 with intensive counselling, and EUR 3,300 with pharmacotherapy. The incremental cost per QALY gained was EUR 16,900 with minimal counselling, EUR 8,200 with intensive counselling, and EUR 2,400 with pharmacotherapy.
The incremental cost per QALY gained was EUR 4,600 with intensive counselling versus minimal counselling, and pharmacotherapy was dominant over intensive counselling as it saved costs and was more effective.
The alternative scenarios considered in the sensitivity analysis did not change the ranking of the interventions and did not have a substantial impact on the cost-effectiveness ratios. The most sensitive parameter was the treatment effect, but all interventions remained cost-effective, compared with no intervention, at standard Dutch thresholds.