Measuring the level of severity in pharmacoeconomic analyses : an empirical approach

Abstract

Background: Economic evaluations are increasingly being used to inform decision makers regarding the allocation of scarce health care resources. In reimbursement applications to the Norwegian Drug Reimbursement Scheme the cost-utility analysis (CUA) is a common feature, expressing the cost-effectiveness of a treatment. Norwegian Medicines Agency (NoMA),which administers the scheme, is interested in supplementing the existing dossier with measurements of the conditions severity level. During their work on revising the pharmacoeconomic guidelines they identified a lack of empirical studies concerning severity measures (NoMA, 2011b).

Objective: To find out how to operationalize severity measurements in a Norwegian context and investigate the implications of the included severity measures; providing a contribution to the discussion of severity level in Norway.

Method: An explorative approach with a systematic literature review to identify different severity measures. Quality-adjusted life expectancy (QALE) based on Scandinavian data is developed to establish a reference class for the included conditions. The data material is reimbursement applications received by NoMA in the period 2009-2011, including 20 cases in the analysis.

Results: Two severity measures, Absolute shortfall (AS) and Proportional shortfall (PS), are included and operationalized. They both make use of Quality-adjusted lifeyar (QALY) utility values, but have a fundamental difference in how the age of the patient is handled. None of them stands out as being clearly superior regarding existing policy and studies concerning the public opinion.

Conclusions: NoMA and other governmental agencies could get useful information to utilize in resource allocation if doing a more consistent evaluation of medical conditions’ severity levels. AS favored younger individuals, but the age component was reduced by including discounting in the procedure. PS was more sensitive to conditions with an expected death in near future independent of patient’s age. The thesis identifies various components that have to be addressed to developers of pharmacoeconomic models to achieve valid measurements. This type of methodology are not widespread and it would be interesting to see more research done on applying severity measures to real-life data to develop new and refine existing principles.