Validation of the revised Bakas Caregiving Outcomes Scale in Greek caregivers of patients with advanced cancer receiving palliative radiotherapy

Caregiver burden considerably affects the lives of families providing care to people with advanced cancer. The aim of this study was to validate the Greek translation of the revised Bakas Caregiving Outcomes Scale (BCOS) with a sample of informal caregivers of people with advanced cancer receiving outpatient palliative radiotherapy.

Following a formal "forward-backward" method to translate the original BCOS into Greek, the scale was administered to 100 consecutive family caregivers. Participants also completed the Greek Hospital Anxiety and Depression Scale (G-HADS) and five quality-of-life related linear analogue scale assessment (LASA) scales. Validity and reliability analyses were performed.

The Cronbach's alpha coefficient for the total BCOS score was 0.83. Test-retest reliability analysis in a subgroup of caregivers (n = 40) revealed good short-term stability over a 2-week interval. Exploratory factor analysis generated a one-factor structure for the Greek translation, which was further confirmed through confirmatory factor analysis. Construct validity was supported through the scale's high correlations with G-HADS anxiety (-0.524; p <0.001) and depression (-0.533; p <0.001) scores, and LASA quality of life scores (0.696; p <0.001). The BCOS discriminated well between groups of caregivers with different levels of quality of life. A total score of 52.5 offered high sensitivity (91 %) and specificity (86 %) in detecting highly burdened caregivers.

The Greek version of the BCOS is a psychometrically sound instrument that can be usefully implemented into clinical practice to identify family caregivers in need for support, and stimulate relevant research in our country.