Development and validation of a questionnaire to assess quality of life in Australian adults with type 1 diabetes: a pilot psychometric study

The burdensome nature of managing type 1 diabetes (T1D) can influence psychological well-being and reduce quality of life (QoL). This pilot study aims to develop and validate a new questionnaire identifying factors impacting the QoL of Australian adults with T1D. Questionnaire development included literature review, pre-testing, semi-structured interviews, expert evaluation, and pilot testing. Questionnaire validation involved an exploratory factor analysis (EFA) to identify the initial factor structure. Confirmatory factor analysis (CFA) determined domain validity. Further statistical analysis included convergent, relative, predictive validity, and reliability. The initial questionnaire had 28-items relating to physical, psychological, social, and dietary well-being. CFA revealed ‘psychological’ and ‘social’ items underpinned the four questionnaire domains. The four domains identified were: (1) ‘Coping and Adjusting’ (4-items), (2) ‘Fear and Worry’ (4-items), (3) ‘Loss and Grief’ (3-items), and (4) ‘Social Impact’ (4-items). Significant correlations were revealed between ‘Coping and Adjusting’ and HbA1c (r_s = − 0.44, p < 0.01) and ‘Social Impact’ and HbA1c (r_s = 0.13, p < 0.01) respectively. Acceptable convergent validity and reliability (test–retest, internal consistency) was observed in all domains. Our study concludes that dietary well-being does not independently impact QoL but is interwoven with psychological factors.