Challenges in Valuing Temporary Health States for Economic Evaluation: A Review of Empirical Applications of the Chained Time Trade-Off Method

A new paper titled “Challenges in Valuing Temporary Health States for Economic Evaluation: A Review of Empirical Applications of the Chained Time Trade-Off Method” has been published in Value in Health.

A new paper titled “Challenges in Valuing Temporary Health States for Economic Evaluation: A Review of Empirical Applications of the Chained Time Trade-Off Method” has been published in Value in Health. The paper is co-authored by OHE’s David Mott, with Julija Stoniute and Dr Jing Shen based in the Health Economics Group in the Institute of Health & Society at Newcastle University.

The time trade-off (TTO) technique is commonly used to elicit health state utilities. However, when the health states being valued are temporary, the conventional TTO approach may be unsuitable. A variant of TTO – chained TTO – has been put forward for use when the health states being valued are temporary. Chained TTO uses a two-stage approach. In the first stage, the temporary health state is valued against another temporary health state (known as the anchor state). Death is only introduced in the second stage, where the anchor state is valued using conventional TTO, often using a longer time horizon.

Little research has been done on how chained TTO should be conducted. This paper presents a systematic literature review of existing published chained TTO studies. In total, 9 studies were identified for the review. All of the reviewed studies used face-to-face interviews, most had small sample sizes (<100), and all studies valued a small number of health states (<7), with time horizons typically ranging from 4 weeks to 1 year. All studies discussed methodological issues relating to the use of chained TTO, and some compared the results with those generated using other preference elicitation methods.

On the whole chained TTO appears to be feasible, consistent and responsive. The limitations of conventional TTO when valuing temporary health states are well known, and chained TTO may prove to be a useful alternative. However, there are challenges that remain, such as defining a suitable anchor state and determining the ideal time horizon for each stage of the process. The limited number of published studies suggests that further research using this method is needed.

The systematic review was conducted as part of an internship project, funded by The Health Foundation. The results of the review was used to inform a TTO study conducted as part of the OPEN trial.