This chapter starts with the initial proposal for building the HealthAgeingMod model-system. It then follows through the major steps involved in carrying out the initial literature searches; research on how to implement the novel features proposed; assessment of the best way to treat each element of the system; examination of the data and methods to be used; and the building and validation of a complex individual-based and nationally representative chronic disease model-system. It also documents the difficulties and modeling pitfalls encountered and describes how the project evolved from the initial detailed plans, through the building of a prototype, and the final, validated version of HealthAgeingMod.
The outcome is a policy relevant tool in which chronic disease progression models are linked to a population-wide microsimulation projection model. The system accounts for individuals’ demographic, socio-economic and health characteristics, comorbidities, health expenditures, quality of life, work prospects. Its outputs are estimates of the costs and benefits of simulated policy interventions. HealthAgeingMod is a validated personlevel system able to simultaneously account for diabetes and cardiovascular disease (CVD), with the possibility of extensions to other major chronic diseases.
Keywords: Common health risk factors, diabetes, cardiovascular disease, comorbidities, chronic disease onset and prevalences, nationally representative data sources, psychological distress, model building.