Perceived social support and social/non-social problematic smartphone use among Chinese university students: a cross-sectional study of indirect associations via social anxiety

Introduction Problematic smartphone use (PSU) is associated with poorer sleep, impaired attention, reduced academic functioning, and mental and physical health risks. This concern is salient among Chinese university students with smartphone engagement and elevated social anxiety (SA). Prior research links perceived social support (PSS) to lower anxiety and links SA to PSU severity, yet direct PSS–PSU associations are often modest or mixed. Moreover, most studies treat PSU as a unitary construct or examine subtypes, leaving subtype-specific tests of the PSS → SA → PSU pathway limited. Therefore, this study examined whether PSS was indirectly associated with social PSU (SPSU) and non-social PSU (NSPSU) via SA among Chinese university students. Methods We conducted a cross-sectional self-report survey among undergraduates from one university in Jiangsu, China ( N = 248; 58.1% women, 41.9% men; M age = 19.69 years, SD = 1.53). Structural equation modeling (SEM) with maximum-likelihood estimation and bootstrapping (5,000 resamples) was used to estimate indirect associations adjusting for gender, age, and subjective socioeconomic status. Common method variance was assessed using Harman’s single-factor test. Results The structural model showed marginally acceptable fit (CFI = 0.90; TLI = 0.89; RMSEA = 0.07 [90% CI = (0.06, 0.08)]; SRMR = 0.07). PSS was negatively associated with SA ( β = −0.26, p = 0.002). SA was positively associated with SPSU ( β = 0.51, p = 0.001) and NSPSU ( β = 0.55, p < 0.001). Bootstrapped estimates indicated significant indirect associations from PSS to SPSU and NSPSU via SA [SPSU: β _ind = −0.13, BC 95% CI (−0.36, −0.07); NSPSU: β _ind = −0.14, BC 95% CI (−0.39, −0.07)]. Direct paths from PSS to SPSU and NSPSU were non-significant; the PSS → SPSU direct effect was opposite in sign to the indirect effect. Harman’s test suggested limited common method bias (first factor = 29.124%). Conclusion Social anxiety was associated with both PSU subtypes and was more strongly linked to NSPSU than SPSU in this sample. Perceived social support was indirectly associated with lower PSU through lower social anxiety, whereas direct associations with PSU subtypes were not significant. Given the cross-sectional design, findings reflect theory-consistent associations rather than causal effects.