Results. Psychological predictors of treatment response were successfully integrated with the health economic simulation model and allowed new treatment policies to be evaluated.
Health economic modelling has paid limited attention to incorporating the effects patients’ psychological characteristics can have on the effectiveness of a treatment. In attempting to represent the real world this is a substantial limitation, particularly when modelling diseases that involve a large element of self-care or when evaluating interventions that aim to change health behaviours.
The objective of this study was to test the feasibility of incorporating psychological prediction models of treatment response within an economic model of a diabetes structured education programme: Dose Adjustment For Normal Eating (DAFNE).
Data from the National Institute for Health Research (NIHR) DAFNE Research Programme were used to support all analyses*. Three regression models were used to investigate the relationships between patients’ baseline psychological characteristics (e.g. beliefs about diabetes, confidence in performing self-care behaviours, fear of hypoglycaemia) and their 12-month blood glucose (% HbA1c)response to DAFNE. The regression prediction models were integrated with a patient-level simulation model of type 1 diabetes (Sheffield Type 1 Diabetes Model) to evaluate the cost-effectiveness of two new policies:
Providing DAFNE only to predicted responders
Offering a follow-up intervention to predicted non-responders
Response was defined as a reduction in HbA1c of 0.5% or more. Both new policies were compared with current practice of providing DAFNE to all adults with type 1 diabetes and not offering a follow-up intervention.
The model estimated costs and quality-adjusted life-years (QALYs) over a 50-year time horizon from a UK National Health Service (NHS) perspective. Deterministic sensitivity analyses were conducted.
By collecting data on psychological variables for a subgroup of patients before an intervention, we can construct predictive models of treatment response to behavioural interventions and incorporate these into health economic simulation models to investigate more complex treatment policies. Further research using this methodology is indicated.
Accounting for Psychological Determinants of Treatment Response in Health Economic Simulation Models of Behavioural Interventions
A Case Study in Type 1 Diabetes
Jen Kruger1, Alan Brennan1, Praveen Thokala1, Debbie Cooke2, Rod Bond3 and Simon Heller4
1Health Economics and Decision Science, ScHARR, University of Sheffield, UK., 2Department of Epidemiology & Public Health, University College London, UK.,
3School of Psychology, University of Sussex, UK., 4Academic Unit of Diabetes, Endocrinology and Metabolism, University of Sheffield, UK.
Figure 1The cost-effectiveness of providing DAFNE only to predicted responders vs. current practice
Figure 2The cost-effectiveness of providing a follow-up intervention costing the same as the original DAFNE intervention vs. current practice
Contact: J. Kruger
Postal address: ScHARR, Regents Court, 30 Regent Street, Sheffield S1 4DA, United Kingdom.
* This study was funded by the NIHR. This poster presents independent research commissioned by the NIHR under the Programme for Applied Research. The views expressed in this poster are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Health.