Description of an individual patient methodology for calculating the cost-effectiveness of treatments for osteoporosis in women

Models of the cost-effectiveness of pharmaceutical interventions for the treatment of osteoporosis have traditionally adopted cohort-based approaches. We present a transition-state model to simulate the experience of individual patients, allowing the full patient history and residential status to influence the probabilities of future fractures at the hip, spine, wrist or proximal humerus. Alongside epidemiological data, we used systematic literature reviews of costs, utilities and efficacy to populate the model for a UK setting. We established a statistical relationship between the inputs and outputs of the individual patient model creating a near instantaneous emulation of the individual patient model. We undertook extensive sensitivity analyses to analyse the uncertainty in the estimated incremental cost per quality-adjusted life year due to uncertainty in the efficacy of the drugs. We provide illustrative results accompanied by individual and multi-interventional cost-effectiveness acceptability curves.