Development of a shyness scale for Chinese high school students

Grounded in Chinese indigenous culture and the psychosocial developmental characteristics of high school adolescents, this study developed and validated a culturally adapted shyness scale for Chinese high school students-the High School Student Shyness Scale (HSSS). The instrument aims to provide a valid and localized psychometric tool for objective shyness assessment and empirical research on adolescent shyness.

The preliminary dimensional framework and items were established through literature review, open-ended questionnaire investigation, and expert review. Participants were recruited from district and county-level high schools in Chongqing, China, covering both urban and rural household registration backgrounds, using a combination of cluster sampling and convenience sampling. The study was conducted in stages: an open-ended questionnaire survey was first conducted with 138 high school students to generate indigenous items; 487 valid samples were used for item analysis and exploratory factor analysis (EFA) to screen items and construct the initial factor structure; an independent cohort of 427 students was administered for confirmatory factor analysis (CFA), alternative model comparisons, measurement invariance tests, multivariate generalizability theory (MGT) analysis, and systematic reliability and validity assessment; an additional 176 students completed a four-week retest to evaluate test-retest reliability; and 200 participants completed the classic Cheek and Buss Shyness Scale to examine the criterion-related validity of the newly developed scale.

The final 18-item HSSS comprises three dimensions: Withdrawal from avoidant speech and behavior, Negative self-consciousness, and Negative emotional experience. EFA using Principal Axis Factoring with Promax rotation and parallel analysis supported a three-factor structure (KMO = 0.947; cumulative variance explained = 50.084%). CFA confirmed that the three-factor model fit well (χ ² /df = 2.798, RMSEA = 0.065, CFI = 0.946, TLI = 0.937, GFI = 0.906, NFI = 0.919), and its fit was superior to that of the one-factor and two-factor models. The higher-order model was mathematically equivalent to the first-order three-factor model, and the bifactor model did not yield clearly interpretable specific factors. The first-order three-factor model was therefore retained as the most parsimonious and interpretable solution. Full measurement invariance across gender was supported (configural, metric, scalar, and strict invariance), whereas strict invariance across grade level was partially supported. MGT analysis yielded an overall scale generalizability coefficient of 0.948 and a reliability coefficient of 0.947, indicating high measurement precision across the three dimensions. The scale demonstrated excellent internal consistency (Cronbach's α = 0.935) and test-retest reliability (r = 0.894). Validity analyses revealed acceptable convergent validity (AVE = 0.510-0.610), content validity (I-CVI ≥ 0.78; S-CVI/Ave = 0.91), and criterion-related validity (r = 0.771, p < 0.001).

The HSSS demonstrates acceptable psychometric properties, including evidence of structural validity, high measurement precision, and measurement invariance across gender and grade level. The core three-factor structure was broadly replicated in an independent sample, although the fit was somewhat less optimal than in the primary sample. As a standardized and reliable psychometric instrument, it is suitable for quantitative shyness assessment and related empirical research among Chinese high school populations.