A Longitudinal Study on the Relationship Between Family Size and Instrumental Activities of Daily Living: The Masking Effect of Depressive Symptoms.

Purpose: According to use and disuse theory, the decreasing size of families in China may have a considerable influence on older adults' health. However, research on the associations among family size, depression, and instrumental activities of daily living (IADL) in this population is limited. Thus, the current study examined the role of depression on the impact of family size on IADL and explored the differences between urban and rural areas.

Method: Mediation analyses were performed with data from 7,290 older adults aged ≥60 years from the Harmonized China Health and Retirement Longitudinal Study in 2011, 2013, 2015, and 2018, using stepwise regression and bootstrap methods.

Results: Family size had a positive impact on IADL limitations of older adults (0.29, p < 0.01), and the masking effects of depressive symptoms had a partial effect of family size on older adults' IADL. However, these effects only exist in rural areas.

Conclusion: Providing emotional support through psychological counseling and guiding caregivers to provide moderate care support is crucial, particularly in rural areas, for alleviating depressive symptoms due to changes in family size and maintaining independent living skills among older adults. [Research in Gerontological Nursing, 17(4), 165-175.].