TY - JOUR
T1 - An exploration of differences between Japan and two European countries in the self-reporting and valuation of pain and discomfort on the EQ-5D
AU - Feng, Yan
AU - Herdman, Mike
AU - van Nooten, Floortje
AU - Cleeland, Charles
AU - Parkin, David
AU - Ikeda, Shunya
AU - Igarashi, Ataru
AU - Devlin, Nancy J.
N1 - Publisher Copyright:
© 2017, The Author(s).
PY - 2017/8/1
Y1 - 2017/8/1
N2 - Purpose: To investigate the systematic differences in the self-reporting and valuation of overall health and, in particular, pain/discomfort between three countries (England/UK, Japan, and Spain) on the EQ-5D. Methods: Existing datasets were used to explore differences in responses on the EQ-5D descriptive system between Japan (3L and 5L), the UK (3L), England (5L), and Spain (5L), particularly on the dimension of pain/discomfort. The role of different EQ dimensions in determining self-reported overall health scores for the EuroQol visual analog scale (EQ-VAS) was investigated using ordinary least squares regression. Time trade-off (TTO) results from Japanese and UK respondents for the EQ-5D-3L as well as Japanese and English respondents for the EQ-5D-5L were compared using t tests. Results: For the EQ-5D-3L, a higher percentage of respondents in Japan than in the UK reported ‘no pain/discomfort’ (81.6 vs 67.0%, respectively); for the EQ-5D-5L, the proportions were 79.2% in Spain, 73.2% in Japan, and 63–64% in England, after adjusting for age differences in samples. The ‘pain/discomfort’ dimension had the largest impact on respondents’ self-reported EQ-VAS only for EQ-5D-3L in Japan. Using the EQ-5D-3L, Japanese respondents were considerably less willing to trade off time to avoid pain/discomfort than the UK respondents; for example, moving from health state, 11121 (some problems with pain/discomfort) to 11131 (extreme pain/discomfort) represented a decrement of 0.65 on the observed TTO value in the UK compared with 0.15 in Japan. Using the EQ-5D-5L, Japanese respondents were also less willing to trade off time to avoid pain/discomfort than respondents in England; however, the difference in values was much smaller than that observed using EQ-5D-3L data. Conclusions: This study provides evidence of between-country differences in the self-reporting and valuation of health, including pain/discomfort, when using EQ-5D in general population samples. The results suggest a need for caution when comparing or aggregating EQ-5D self-reported data in multi-country studies.
AB - Purpose: To investigate the systematic differences in the self-reporting and valuation of overall health and, in particular, pain/discomfort between three countries (England/UK, Japan, and Spain) on the EQ-5D. Methods: Existing datasets were used to explore differences in responses on the EQ-5D descriptive system between Japan (3L and 5L), the UK (3L), England (5L), and Spain (5L), particularly on the dimension of pain/discomfort. The role of different EQ dimensions in determining self-reported overall health scores for the EuroQol visual analog scale (EQ-VAS) was investigated using ordinary least squares regression. Time trade-off (TTO) results from Japanese and UK respondents for the EQ-5D-3L as well as Japanese and English respondents for the EQ-5D-5L were compared using t tests. Results: For the EQ-5D-3L, a higher percentage of respondents in Japan than in the UK reported ‘no pain/discomfort’ (81.6 vs 67.0%, respectively); for the EQ-5D-5L, the proportions were 79.2% in Spain, 73.2% in Japan, and 63–64% in England, after adjusting for age differences in samples. The ‘pain/discomfort’ dimension had the largest impact on respondents’ self-reported EQ-VAS only for EQ-5D-3L in Japan. Using the EQ-5D-3L, Japanese respondents were considerably less willing to trade off time to avoid pain/discomfort than the UK respondents; for example, moving from health state, 11121 (some problems with pain/discomfort) to 11131 (extreme pain/discomfort) represented a decrement of 0.65 on the observed TTO value in the UK compared with 0.15 in Japan. Using the EQ-5D-5L, Japanese respondents were also less willing to trade off time to avoid pain/discomfort than respondents in England; however, the difference in values was much smaller than that observed using EQ-5D-3L data. Conclusions: This study provides evidence of between-country differences in the self-reporting and valuation of health, including pain/discomfort, when using EQ-5D in general population samples. The results suggest a need for caution when comparing or aggregating EQ-5D self-reported data in multi-country studies.
KW - Between-country comparison
KW - EQ-5D
KW - Health state valuation
KW - Patient-reported outcomes
KW - Self-reported pain/discomfort
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U2 - 10.1007/s11136-017-1541-5
DO - 10.1007/s11136-017-1541-5
M3 - Article
C2 - 28343350
AN - SCOPUS:85016060917
SN - 0962-9343
VL - 26
SP - 2067
EP - 2078
JO - Quality of Life Research
JF - Quality of Life Research
IS - 8
ER -