Translation and cross-cultural adaptation of the mSQUASH into European Portuguese

Regular physical activity is recommended for all patients with axial spondyloarthritis (axSpA), but measuring its frequency, duration and intensity can be challenging. The modified Short Questionnaire to ASsess Health-enhancing physical activity (mSQUASH) is a patient-reported outcome measurement designed to assess daily physical activity in patients with axSpA. This study aimed to translate the mSQUASH into European Portuguese and to perform field testing with cognitive debriefing interviews in patients with axSpA in Portugal.

The mSQUASH was translated into European Portuguese following the Beaton method. Two bilingual translators independently translated the questionnaire from English to European Portuguese, which was then harmonized into a consensus version. Two other translators back translated the synthesized version into English. Translation discrepancies were resolved within a scientific committee, resulting in a preliminary version. The preliminary version was field-tested through semi-structured one-to-one interviews with 10 patients with axSpA with a broad range of socio-demographic and clinical characteristics.

The translation process was completed without major issues and minor disagreements were resolved in consensus meetings. During field testing, all participants found the questionnaire clear and appropriate. The median time to complete the questionnaire was 4 minutes and 15 seconds. Patient's feedback led to the correction of minor spelling errors and the addition of examples to the item "Home maintenance", which was misinterpreted as household activities by half of patients. The final version of the questionnaire, incorporating patient feedback, was approved by the scientific committee.

The European Portuguese version of the mSQUASH demonstrated good linguistic properties and performed well in a field test with axSpA patients. Further studies are needed to evaluate its psychometric properties.