New Publications: Study Design Considerations in Health State Valuation Research

Recently published are two articles exploring the design of health state valuation studies. The articles are authored by OHE’s Koonal Shah, in collaboration with Brendan Mulhern of the University of Technology Sydney, Louise Longworth of Brunel University London, Bas Janssen of the EuroQol Office, and Rachel Ibbotson of Sheffield Hallam University.

The first article, published in the January/February 2016 issue of Value in Health, reports the methods and findings of a study assessing two comparator health states (‘full health’ and EQ-5D-5L health state 11111) for use in time trade-off exercises. An earlier version was published as a EuroQol Working Paper. The main finding is that EQ-5D-5L values elicited using the time trade-off method (see Figure 1) are not greatly affected by the choice of comparator state.

Access the paper here.

Figure 1: Screenshots from the time trade-off survey (left: full health; right: 11111)

The second article, forthcoming in the same journal and available as an ‘Article in Press’, examines the impact of ordering effects – specifically, whether EQ-5D-5L values are affected by the order in which the five health dimensions are presented to survey respondents. The sample was split into three study arms – each presented the dimensions in a different order. A variety of statistical tests and regression analyses were used to assess differences in time trade-off and discrete choice experiment data across the three arms. The results show that the dimension coefficients differed across arms. This highlights the fact that the order of dimensions is a key consideration in the design of health state valuation studies.

Access the paper here.

Both articles are based on a wider study that was funded by the EuroQol Research Foundation. However, the views expressed do not necessarily reflect the views of the EuroQol Research Foundation.

A summary of the first article will be featured in the January/February issue of Value & Outcomes Spotlight.

Full references:

Shah, K., Mulhern, B., Longworth, L. and Janssen, M.F., 2016. An empirical study of two alternative comparators for use in time-trade off studies. Value in Health, 19, pp.53-59.

Shah, K., Mulhern, B., Janssen, M.F., Longworth, L. and Ibbotson, R., 2016.  Valuing health using time trade-off and discrete choice experiment methods: does dimension order impact on health state values? Value in Health, Article in Press. DOI: http://dx.doi.org/10.1016/j.jval.2015.11.005

Posted in EQ-5D and PROMs, Research | Tagged External publications