Portuguese validation of the Adult Carer Quality of Life Questionnaire (AC-QoL)

Abstract

Background. Assuring informal carers' quality of life (QoL) must be a priority for public health policies and practices. The Adult Carer Quality of Life Questionnaire (AC-QoL) is a recent and valid instrument, overpassing limitations of previous tools, and being already used among informal stroke carers. This study aimed to assess the feasibility, reliability and validity of the AC-QoL among Portuguese informal carers of stroke survivors. Methods. The linguistic adaptation of the AC-QoL was performed. Informal carers (n = 212) of stroke survivors hospitalized between September 2018 and August 2019 in all Stroke Units of the North of Portugal (n = 12) were invited to participate, 18 to 24 months post-stroke. Data on sociodemographic characteristics, psychological profile, burden and QoL were collected using a structured questionnaire. The psychometric properties of the AC-QoL were investigated through exploratory and confirmatory factor analyses. Cronbach's alpha was used to measure internal consistency. Construct validity was assessed through the association of the overall score of AC-QoL with anxiety and depressive symptoms, burden and sociodemographic characteristics. Results. Exploratory factor analysis supported the original eight-factor structure of the AC-QoL, revealing an adequate goodness of fit to the study sample (X2(674)=1145.926; CFI=0.916; TLI=0.908; RMSEA=0.058). The AC-QoL showed a high degree of reliability, with Cronbach's scores for the subscales ranging from 0.64 to 0.97 and a Cronbach's alpha of 0.91 for the overall score. Anxiety symptoms (p < 0.001), depression symptoms (p < 0.001) and burden (p < 0.001) were inversely associated with the overall score of AC-QoL. Younger (p = 0.032) and employed (p = 0.021) informal carers presented more frequently higher scores of overall QoL, than those older and unemployed. Conclusions. The Portuguese version of the AC-QoL is a comprehensive, simple, reliable and valid instrument to assess informal stroke carers' QoL.