Development and validation of a digital self-harm measurement: a population-based study of adolescents in China.

Background: The purpose of this study was to develop a digital self-harm scale suitable for Chinese adolescents, and to test its reliability and validity.

Methods: Through semi-structured interview, literature analysis and expert evaluation, the initial questionnaire was developed, and 1651 students from three middle schools in Jilin Province were selected for questionnaire survey. Item analysis and exploratory factor analysis were carried out, and 843 students were selected for confirmatory factor analysis, convergent validity, discrimination validity, criterion validity, content consistency reliability and retest reliability.

Results: The results showed that the digital self-harm scale consisted of eight items divided into two factors, namely External self image harm and Inner self emotional harm. And 73.47% of the total variance was explained. The two-factor structure model fitted well (²χ/df = 4.2, CFI = 0.994, TLI = 0.989, SRMR = 0.01, RMSEA = 0.062). The total score and each factor score of the digital self-harm scale were negatively correlated with sleep duration, and positively correlated with other criteria. The Cronbach α coefficient of the total scale and each factor was 0.938-0.965, and the retest reliability was 0.983-0.991.

Limitations: The Inner self emotional harm dimension has few questions, the relationship and mechanism between digital self-harm and non-suicidal self-injury is not deep enough.

Conclusions: The digital self-harm scale developed in this study has good validity and reliability, and can be used as a measurement tool to assess the digital self-harm of Chinese adolescents.