Low health literacy and psychological symptoms potentially increase the risks of non-suicidal self-injury in Chinese middle school students

BACKGROUND: Low health literacy (HL) has been known to be involved in various risk behaviors and mental disorder among adolescent. The purpose of this study was to examine the independent and interactive association between HL and self-reported mental health with non-suicidal self-injury (NSSI) in Chinese middle school students. METHODS: Twenty five thousand three hundred seventy-eight junior and high school students in China were enrolled in this study. The outcomes were self-reported HL, psychological symptoms and NSSI. Logistic regression models were conducted to examine relations between them. RESULTS: The prevalence of NSSI was 27.5 %. Low HL was significantly associated with NSSI (OR = 2.538, 95 % CI: 2.335–2.758). Psychological symptoms were significantly positively correlated with NSSI (OR = 3.872, 95 % CI: 3.637–4.123). Low HL and psychological symptoms were independently and interactively associated with increased risks of NSSI. CONCLUSIONS: These results suggest that Chinese middle school students with low HL and psychological symptoms are intending to exhibit NSSI. The intervention programs of mental health and behavior problems should enhance HL levels and attenuate the severity of psychological symptoms. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12888-016-1035-y) contains supplementary material, which is available to authorized users.