Smartphone addiction, work duration and job burnout in nursing interns: a multicenter cross-sectional study

Background Job burnout prevalence among healthcare workers is high, posing significant threats to physical or mental health, care quality, and patient safety. While work duration is an established risk factor for burnout, the impact of smartphone addiction and its potential synergistic effect with prolonged work hours on job burnout remains unclear. Methods In this multicenter cross-sectional study, a total of 1,055 nursing interns were recruited from hospitals in Hunan Province, China. Smartphone addiction was measured with the Smartphone Addiction Scale-Short Version, and job burnout was evaluated using the Maslach Burnout Inventory-General Survey (MBI-GS). Logistic regression was used to estimate the associations between smartphone addiction, work duration and job burnout. Additive interactions were examined using relative excess risk due to interaction (RERI) and attributable proportion (AP) metrics. Results Among 1,055 nursing interns, job burnout prevalence was higher with smartphone addiction (47.5% vs 38.5%; P = 0.012). Each 1-unit increase in addiction score elevated MBIGS by 0.471 (95% CI: 0.360–0.583), while addiction status showed borderline association with job burnout (OR = 1.33, 95% CI: 0.99–1.78). Additionally, participants with work duration more than 50 hours had significant increased odds of job burnout as compared to those with work duration less than 40 hours (OR = 1.97, 95% CI: 1.22–3.19). Notably, smartphone addiction combined with prolonged work duration synergistically exhibited a markedly increased odds of job burnout (OR = 3.24, 95% CI: 1.63–6.51; RERI = 1.948, 95% CI: 0.240–3.656; AP = 0.601, 95% CI: 0.293–0.908). Conclusions This study suggested that both smartphone addiction and prolonged work duration are independent risk factors for job burnout among nursing interns, and they exhibit synergistic effects on burnout.