The interplay of factors shaping quality of life among informal caregivers of people with visual impairment: moving beyond single-determinant models

Informal caregivers of people with visual impairment (VI) experience multidimensional challenges that substantially affect their quality of life (QoL). Existing literature often examines determinants in isolation and overlooks complex interactions and unobserved heterogeneity. This paper addresses the QoL of caregivers of visually impaired individuals through a comprehensive multivariate analysis that accounts for complex interactions and unobserved heterogeneity among determinants. Data were collected from 251 caregivers of people with VI. Caregiver QoL was analyzed using a “correlated random parameter ordered probit model” to account for “unobserved heterogeneity” and interdependence among determinants. The analysis integrated demographic, socioeconomic, clinical, psychological, and social factors to capture the multidimensional nature of caregiver well-being. Econometric modeling revealed that caregiver QoL was shaped by cumulative, interacting effects rather than isolated influences. Mid-life (35–50 years old), female, and single caregivers experienced significantly higher risks of poor QoL. Random parameters show 57.1% of single caregivers inclining toward lower QoL. Overall, 54.3% of female caregivers were predisposed to lower QoL outcomes. Financial strain and transportation limitations intensified vulnerability, with financial hardship yielding the highest low-category marginal effects of 0.0690 and 0.1068. Moreover, cataracts drove a 42% combined probability of low QoL, outstripping glaucoma (27%). Vertical son caregivers exhibited a 27% combined probability of low QoL compared to 7% for horizontal sisters. Subjective health satisfaction emerged as the strongest predictor, boosting “good” and “very good” QoL by 16.19% and 33.58%. Finally, correlated random parameters revealed substantial unobserved heterogeneity within the latent system. A strong positive correlation (0.651) between singlehood and social relationships demonstrated that spousal support and social networks are tightly intertwined, while a positive correlation (0.167) between the single and female parameters confirmed that single women face compounded, multi-layered vulnerabilities. The findings indicated the need for tailored policy interventions for informal caregivers, including financial assistance, accessible transportation, and structured support networks for single caregivers, routine health assessments, and mental health referral pathways. Addressing caregiver QoL through integrated, subgroup-specific policies will strengthen caregiving sustainability and improve care quality for visually impaired populations.