International Journal of Health Policy and Management

International Journal of Health Policy and Management

Measuring the Benefits of Healthcare: DALYs and QALYs – Does the Choice of Measure Matter? A Case Study of Two Preventive Interventions

Document Type : Original Article

Authors
Federico Augustovski 1
Lisandro D. Colantonio 2
Julieta Galante 3
Ariel Bardach 1
Joaquín E. Caporale 1
Víctor Zárate 4
Ling Hsiang Chuang 5
Andres Pichon-Riviere 1
Paul Kind 6
1 Institute for Clinical Effectiveness and Health Policy (IECS-CONICET), Buenos Aires, Argentina
2 University of Alabama at Birmingham, Birmingham, AL, USA
3 Cardiff University, Cardiff, UK
4 Facultad de Medicina, Universidad San Sebastian, Santiago, Chile
5 Pharmerit, Rotterdam, The Netherlands
6 University of Leeds, Leeds, UK
10.15171/ijhpm.2017.47
Abstract
Background
The measurement of health benefits is a key issue in health economic evaluations. There is very scarce empirical literature exploring the differences of using quality-adjusted life years (QALYs) or disability-adjusted life years (DALYs) as benefit metrics and their potential impact in decision-making.

 
Methods
Two previously published models delivering outputs in QALYs, were adapted to estimate DALYs: a Markov model for human papilloma virus (HPV) vaccination, and a pneumococcal vaccination deterministic model (PNEUMO). Argentina, Chile, and the United Kingdom studies were used, where local EQ-5D social value weights were available to provide local QALY weights. A primary study with descriptive vignettes was done (n = 73) to obtain EQ-5D data for all health states included in both models. Several scenario analyses were carried-out to evaluate the relative importance of using different metrics (DALYS or QALYs) to estimate health benefits on these economic evaluations.

 
Results
QALY gains were larger than DALYs avoided in all countries for HPV, leading to more favorable decisions using the former. With discounting and age-weighting – scenario with greatest differences in all countries – incremental DALYs avoided represented the 75%, 68%, and 43% of the QALYs gained in Argentina, Chile, and United Kingdom respectively. Differences using QALYs or DALYs were less consistent and sometimes in the opposite direction for PNEUMO. These differences, similar to other widely used assumptions, could directly influence decision-making using usual gross domestic products (GDPs) per capita per DALY or QALY thresholds.

 
Conclusion
We did not find evidence that contradicts current practice of many researchers and decision-makers of using QALYs or DALYs interchangeably. Differences attributed to the choice of metric could influence final decisions, but similarly to other frequently used assumptions.
Keywords
Quality-Adjusted Life Year (QALY)
Disability-Adjusted Life Year (DALY)
Health Benefit Measure
Economic Evaluation
Subjects
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International Journal of Health Policy and Management
Volume 7, Issue 2
2018
Pages 120-136

  • Received Date 09 May 2016
  • Revised Date 09 January 2017
  • Accepted Date 10 April 2017
  • First Published Date 01 February 2018
  • Published Date 01 February 2018