Does the Time Trade-Off Method Reflect Health-Related Quality of Life? A Mixed-Methods Analysis of Preference Measures 10 Years After Aneurysmal Subarachnoid Hemorrhage

Abstract

To investigate if the time trade-off (TTO) method reflects health-related quality of life (HRQoL) 10 years after an aneurysmal subarachnoid hemorrhage (aSAH). A cross-sectional study with a mixed-methods approach was used to follow up 208 patients treated for aSAH. Data were collected with intramethod mixing; the quantitative data consisted of the EQ-5D-3L instrument and a TTO question, and the qualitative data comprised motivations to the TTO answer. The quantitative data were analyzed statistically and comparisons were made between participants willing to trade off years and those not willing to trade off years. The qualitative data were merged in a matrix and analyzed with manifest content analysis. Participants willing to trade off years scored significantly lower HRQoL, and the correlation between EQ-5Dindex and EQ VAS to TTO values were rs= 0.369 (P < 0.001) and rs= 0.345 (P < 0.001), respectively. In the content analysis, 4 categories emerged: perceived full health or satisfactory life; adaptability and managing strategies; the importance of hope and meaning in life; and unacceptable changes do not make life worth living. The results showed that several reasons other than health status were evident when expressing the willingness to trade off or not trade off life-years. Individuals willing to trade off years showed significantly poorer HRQoL; however the TTO method did not seem to fully reflect HRQoL. Most participants did not want to trade off years, despite their living with severe disability, making it difficult to fully rely on the TTO method in evaluation of medical outcome.