To understand the relationship between smartphone use and self-rated health among rural middle-aged and older adults, investigate its heterogeneity among different groups, and explore the mediating effect of health-promoting behaviors, so as to provide scientific recommendations for promoting healthy aging in rural areas.

Based on data from the 2020 China Rural Revitalization Survey (CRRS), multiple linear regression models were established to examine the direct effect of smartphone use (including whether to use, difficulty of use, and duration of use) on self-rated health among rural middle-aged and older adults. Heterogeneity tests were conducted based on gender, age, and education level. The mediating effect of health-promoting behaviors between smartphone use and self-rated health was analyzed using a three-step regression method and the Bootstrap test.

A total of 2 876 respondents were included, with an average age of (58.82 ± 8.54) years. Among them, 2 266 (78.79%) were male, 2 221 (77.23%) used smartphones, 958 (43.13%) reported no difficulty using smartphones, the average daily smartphone use duration was (2.44 ± 1.86) h, the average health-promoting behavior score was (4.66 ± 2.14) points, and 476 (16.55%) self-rated their health as very good. Multiple linear regression results showed that smartphone use among rural middle-aged and older adults had a significant positive impact on their health-promoting behaviors (β = 0.182) and self-rated health (β = 0.135). Smartphone use duration had a significant positive impact on their health-promoting behaviors (β = 0.076) and self-rated health (β = 0.032). Smartphone use difficulty had a significant negative impact on their health-promoting behaviors (β = -0.173) and self-rated health (β = -0.169) (all P < 0.05). The positive impact of smartphone use on self-rated health varied among rural middle-aged and older adults of different genders, ages, and education levels. Health-promoting behaviors played a mediating role between smartphone use (three dimensions) and self-rated health (indirect effect values were 0.125, -0.161, and 0.030, respectively), accounting for 91.91%, 95.27%, and 90.91% of the total effect, respectively.

Smartphone use among rural middle-aged and older adults has a positive effect on improving self-rated health, with variations among groups with different genders, ages, and education levels. Health-promoting behaviors play a mediating role between smartphone use and self-rated health among rural middle-aged and older adults.