Comparing the German Translation of the ICECAP-A Capability Wellbeing Measure to the Original English Version: Psychometric Properties across Healthy Samples and Seven Health Condition Groups

As the cross-cultural use of outcome measures grows, it is important to determine
whether these instruments are: appropriate for use in other settings, translated accurately,
and perform in a similar manner to their original tools. This research aimed to
compare the validity of the German translation of the ICECAP-A to the original
English version of the instrument, across healthy adults and seven health condition
groups (arthritis, asthma, cancer, depression, diabetes, hearing loss and heart disease).
Data were analysed from a cross-cultural study, which recruited participants through
online panels in 2012. Data were analysed on capability wellbeing (ICECAP-A),
health-related quality of life (EQ-5D-5L and SF-6D), satisfaction with life (SWLS),
and a series of other condition-specific outcome measures. The ICECAP-A was
assessed for internal consistency, convergent validity and construct validity. 2501
individuals were included in the analysis. The ICECAP-A demonstrated good internal
consistency within Germany and the UK population, and across all seven health
condition sub-groups (α = .74–.86). In both countries, ICECAP-A scores were significantly
correlated with SWLS, SF-6D and EQ-5D-5L scores for healthy participants
and health condition groups (r = .35–.77). Finally, experiencing one of the seven health
conditions (compared to being healthy) was significantly associated with lower levels
of capability wellbeing in the German and UK samples (construct validity). The
German translation of the ICECAP-A yielded valid and reliable data, in both healthy
respondents and the seven health condition groups. Further work could be undertaken
to develop a German specific value-set for the ICECAP-A.
Keywords ICECAP-A . German translation . Cultural validation