Reliability and Validity of Early Adolescent Mental Health Scale: An Analysis of Cross-Sectional and Longitudinal Data of the Global Early Adolescent Study

Objective Assessment of mental health problems among young adolescents remains challenging due to a scarcity of suitable measurement tools. A six-item questionnaire, the Early Adolescent Mental Health Scale (EAMHS), was designed to measure the mental health of urban-poor young adolescents and was used in the Global Early Adolescent Study(GEAS). This study aims to assess the reliability and validity of EAMHS. Method Through a secondary data analysis of cross-sectional and longitudinal datasets from the GEAS, we first refined the underlying constructs of EAMHS using Exploratory Factor Analysis and assessed its internal reliability. We then took a set of measurement invariance tests to verify the cross-group, cross-cultural, and cross-time-point validity of the refined scale. Subsequently, we conducted a hypothesis test of construct validity and responsiveness using linear regression, incorporating adjustments for the complex sampling design. We carried out calibration between EAMHS and PHQ-4 through a single-group design Kernel Equipercentile Equating method, and obtained suggested cut-off scores at each site based on the first follow-up (T2) data. The discriminative ability of the scale with suggested cut-offs was assessed against the adolescents' PHQ-4 scores of 6 or higher at the second follow-up (T3) using ROC curve analyses. Results The initial six-item EAMHS was reduced to a four-item version of a unidimensional structure. Scalar invariance was achieved across genders, age groups, and cultures in longitudinal datasets of five study sites. The four-item EAMHS demonstrated acceptable internal reliability and structural validity, as well as excellent construct validity relevant to the PHQ-4. Suggested EAMHS cut-off scores showed fair to good discriminative ability in the subsequent follow-up round, with AUC values ranging from 0.71 (95% CI: 0.64-0.74) in Kinshasa to 0.82 (95% CI: 0.77-0.87) in Shanghai. Conclusion The findings verified EAMHS as a consistent and accurate measure, supporting its use for monitoring and evaluating general emotional disturbance within the study context. Diversity & Inclusion Statement We worked to ensure sex and gender balance in the recruitment of human participants. We worked to ensure that the study questionnaires were prepared in an inclusive way. Diverse cell lines and/or genomic datasets were not available. One or more of the authors of this paper self-identifies as a member of one or more historically underrepresented racial and/or ethnic groups in science. We actively worked to promote sex and gender balance in our author group. We actively worked to promote inclusion of historically underrepresented racial and/or ethnic groups in science in our author group. The author list of this paper includes contributors from the location and/or community where the research was conducted who participated in the data collection, design, analysis, and/or interpretation of the work.