Mapping AcroQoL scores to EQ-5D to obtain utility values for patients with acromegaly

Xavier Badia, Peter Trainer, Nienke R. Biermasz, Jitske Tiemensma, Agata Carreño, Montse Roset, Anna Forsythe, Susan M. Webb

Research output: Contribution to journalArticleResearchpeer-review

4 Citations (Scopus)

Abstract

© 2017 Informa UK Limited, trading as Taylor & Francis Group. Aims: To estimate a preference-based single index for the disease-specific instrument (AcroQoL) by mapping it onto the EQ-5D to assist in future economic evaluations. Materials and methods: A sample of 245 acromegaly patients with AcroQoL and EQ-5D scores was obtained from three previously published European studies. The sample was split into two: one sub-sample to construct the model (algorithm construction sample, n = 184), and the other one to confirm it (validation sample, n = 61). Various multiple regression models including two-part model, tobit model, and generalized additive models were tested and/or evaluated for predictive ability, consistency of estimated coefficients, normality of prediction errors, and simplicity. Results: Across these studies, mean age was 50–60 years and the proportion of males was 36–59%. At overall level the percentage of patients with controlled disease was 37.4%. Mean (SD) scores for AcroQoL Global Score and EQ-5D utility were 62.3 (18.5) and 0.71 (0.28), respectively. The best model for predicting EQ-5D was a generalized regression model that included the Physical Dimension summary score and categories from questions 9 and 14 as independent variables (Adj. R2 = 0.56, with mean absolute error of 0.0128 in the confirmatory sample). Observed and predicted utilities were strongly correlated (Spearman r = 0.73, p <.001) and paired t-Student test revealed non-significant differences between means (p >.05). Estimated utility scores showed a minimum error of ≤10% in 45% of patients; however, error increased in patients with an observed utility score under 0.2. The model’s predictive ability was confirmed in the validation cohort. Limitations and conclusions: A mapping algorithm was developed for mapping of AcroQoL to EQ-5D, using patient level data from three previously published studies, and including validation in the confirmatory sub-sample. Mean (SD) utilities index in this study population was estimated as 0.71 (0.28). Additional research may be needed to test this mapping algorithm in other acromegaly populations.
Original languageEnglish
Pages (from-to)382-389
JournalJournal of Medical Economics
Volume21
Issue number4
DOIs
Publication statusPublished - 3 Apr 2018

Keywords

  • AcroQoL
  • Acromegaly
  • Mapping
  • Utilities

Fingerprint Dive into the research topics of 'Mapping AcroQoL scores to EQ-5D to obtain utility values for patients with acromegaly'. Together they form a unique fingerprint.

Cite this