Measuring the quality of life of people with life-threatening illnesses: the internal structure of the Polish adaptation of the McGill Quality of Life Questionnaire - Revised.

Aim of the study: The McGill Quality of Life Questionnaire has been widely used for people with life-threatening illnesses since 1996. In 2016 Cohen et al. revised the McGill Quality of Life Questionnaire and improved its psychometric properties and length. The aim of the present study was to adapt the McGill Quality of Life Questionnaire - Revised (MQOL-R) into Polish. The study assessed the factorial structure, reliability, and validity of the Polish adaptation of the MQOL-R.

Material and methods: The study had a non-randomised, cross-sectional design. The Polish translation of the MQOL-R was administered to 140 people with life-threatening illnesses. Patients were recruited from acute and palliative care units. Data were analysed using confirmatory factor analysis, and correlational and multiple regression analyses.

Results: The results provide support for the measurement structure of the Polish adaptation of the MQOL-R. Both the overall scale and four subscales have satisfactory internal consistency and the construct and concurrent validity.

Conclusions: The Polish MQOL-R is psychometrically sound and may serve as a valuable asset in research on quality of life of people with life-threatening illnesses.