Improving health-related quality of life instrument translation into South African languages

BACKGROUND: Most health-related quality of life (HRQoL) instruments have been created in English, which can influence their reliability and validity in non-English speaking populations. This study assessed the translation methodology of HRQoL instruments that have been used and translated into South African languages and which could be applied in cost-utility analyses (CUAs). METHODS: A 2019 systematic review was updated with searches conducted in Medline, the Web of ScienceTM (WoSTM) Core Collection and the South African SciELO collection via the WoSTM Platform. Additional searches in Sabinet's African Journals database and on instrument developers' webpages were performed. Only HRQoL instruments suitable for CUAs were included. Articles reporting at least one element of the translation methods were included. Established good practice principles were used to evaluate the translation methodology. RESULTS: Within the 39 publications identified, a dozen translated instruments have been used in South Africa. All instruments used were translated from English and none had originally been created in South Africa. Instrument developers' translations were used more than study investigators' translations. Almost all instrument developer versions met the full translation criteria. No investigator translated instrument met the full translation criteria primarily because recommendations on forward and back translations were not followed. However, this analysis was hampered by a lack of methodological reporting details. The most used instruments, which also had the most translated versions available, were the EQ-5D-3L, SF-36 version 2 and EORTC QLQ-C30. CONCLUSION: Instrument developers' translations more often met recommended translation methodology compared with investigators' versions. The EQ-5D-3L may be best suited for South African economic evaluations and for use in clinical practice, but further work may be needed.