Cost-effectiveness Model

All interventions showed positive incremental net monetary benefit versus usual care in the base case at the £20,000 per QALY threshold. Group interventions outperformed individual interventions because equal clinical effectiveness was assumed while group delivery cost less. Group physical activity promotion had the highest incremental net monetary benefit in the base-case ranking. The primary outcome was an ICER expressed as cost savings per adverse event avoided. The model used a three-state Markov structure with progression-free survival, progressive disease, and death. The study used decision analytic modelling informed by a systematic review and network meta-analysis of randomized controlled trials. The economic perspective was the UK NHS and Personal Social Services. The primary outcome was incremental net monetary benefit at a willingness-to-pay threshold of £20,000 per QALY gained. The model included only direct medical costs from UK cost sources and expressed them in 2023 British pounds.