Lessons From the Qolibri Overall Scale (QOLIBRI-OS) for its use Worldwide

Abstract

Background: The Quality of Life after Brain Injury (QOLIBRI) scale is a recently developed instrument that provides a profile of health-related quality of life (HRQoL) in domains typically affected by traumatic brain injury (TBI). However, for some purposes (e.g. when time is costly or the concentration of respondents limited) it is desirable to have a brief summary measure. This study examined a six-item QOLIBRI Overall Scale (QOLIBRI-OS), and considered whether it could provide an index of HRQOL after TBI. Methods: The properties of the QOLIBRI-OS were studied in a sample of 792 participants after TBI recruited from centres in nine countries covering six languages. An examination of construct validity was undertaken on a sub-sample of 153 participants recruited in Germany who had been assessed on two relevant brief quality of life measures: the Satisfaction With Life Scale and the Quality of Life Visual Analogue Scale. Results: The reliability of the QOLIBRI-OS was good (Cronbach’s ? =0.86, test-retest reliability=0.81), and similar in participants with higher and lower cognitive performance. Factor analyses indicated that the scale is unidimensional. Rasch analysis also showed a satisfactory fit with this model. The QOLIBRI-OS correlates highly with the total score from the full QOLIBRI scale (r=0.87). Moderate to strong relationships were found between the QOLIBRI-OS and the GOSE, SF-36, and Hospital Anxiety and Depression scale (r=0.54 to - 0.76). The QOLIBRI-OS showed good construct validity in the TBI group. Conclusion: The QOLIBRI-OS assesses a similar construct to the QOLIBRI total score and can be used internationally as a brief index and screening instrument of HRQoL for TBI. Key words: Traumatic brain injury, outcome, health-related quality of life, short index.