A challenge to the cross-cultural validity of the SF-36 health survey: factor structure in Maori, Pacific and New Zealand European ethnic groups

This paper reports on a principal component factor analysis of the SF-36 he alth status questionnaire in the three major ethnic groups in New Zealand ( New Zealand Europeans, Maori and Pacific). The SF-36 is hypothesised to hav e a two-dimensional structure with distinct (weakly correlated) mental and physical health components, and support for this structural model has gener ally been found cross-nationally. However, in Maori and Pacific models of h ealth mental and physical dimensions are not generally seen as separable, o r independently functioning. This raises the possibility that the questionn aire's hypothesised structural model would not be supported among Maori and Pacific ethnic groups. This study evaluated that possibility. The results of the analysis showed a similar factor structure among New Zealand Europea ns, and younger Maori (<45 years) to that reported by Ware et al. for Weste rn European countries. Among Pacific people and older Maori (45 years and o ver), however, the factor structure did not clearly differentiate physical and mental health components. Implications are discussed both specific to t he SF-36 (and in particular the use of principal component summary scores), and more generally for the cross-cultural validity of self-reported health status measures. (C) 2000 Elsevier Science Ltd. All rights reserved.