OBJECTIVETo study the prevalence of internet addiction disorder (IAD) in middle school students of Hunan and to explore its risk factors.

METHODS5760 middle school students and their parents were sampled at random in Hunan province using two-stage sampling (stratified sampling and cluster sampling) method. The ten-item diagnosis tool for IAD, self-rating depression scale, self-rating anxiety scale, interpersonal sensitivity subscale of symptom checklist, family assessment device, parenting locus of control scale, and self-developed questionnaire were employed together to gather related data. 95% confidence interval (CI) was used to describe the prevalence of IAD. Chi-square and logistic regression tests were employed respectively to compare the differences of IAD prevalence among different subpopulations and to explore the possible influential factors.

RESULTSThe overall prevalence of IAD in middle school students of Hunan was 5.52%, with 95% CI as 4.84-6.20. IAD prevalence rates between males and females, being or not being monitored in the class and among different grades, showed significant differences (P < 0.05). No statistical difference was found between single child or having siblings in the family, being at key middle school or ordinary middle school, or within residential areas, (P > 0.05). Gender, tired of going to school, anxiety, interpersonal sensitivity, peer influence in haunting at internet bars, father's education level, the number of recreational settings in the community etc. were the influencing factors of IAD, with ORs as 0.281, 3.469, 2.318, 1.710, 1.877, 1.456, 1.273 and 0.726 respectively (P < 0.10).

CONCLUSIONThe prevalence of IAD in middle school students of Hunan was moderate compared to the reported prevalence rates in other provinces. Gender and peer influence in haunting at internet bars and other 6 factors were suggested to be correlated with IAD events.