Development and psychometric evaluation of the stigma scale for caring for individuals with sexually transmitted infections (STISS)- student version

BACKGROUND: While stigmatization by healthcare providers is a primary barrier to effective care for individuals with sexually transmitted infections (STIs), there is currently a lack of specialized, validated instruments to assess these attitudes across the broader spectrum of STI care. This study aimed to fill this gap by developing and psychometrically validating the Sexually Transmitted Infections Stigma Scale (STISS) among future healthcare professionals. The scale provides a standardized framework for identifying and addressing discriminatory perceptions to enhance inclusive clinical practice. METHODS: This methodological study involved the development and validation of the Sexually Transmitted Infections Stigma Scale (STISS) in three stages. Content validity was assessed by a seven-member expert panel using the Davis technique to calculate the Content Validity Index (CVI). Construct validity was evaluated using Exploratory Factor Analysis (EFA, n₁ = 227) with Maximum Likelihood extraction and Promax rotation. The resulting structure was then cross-validated using second-order confirmatory factor analysis (CFA, n₂ = 200). Internal consistency was evaluated using Cronbach’s alpha for the overall scale and its subscales. RESULTS: Content validity was excellent, with a CVI of 1.0. EFA identified a 20-item, four-factor structure (Blame, Concealment, Personal Reaction and Segregation) which explained 68.8% of the total variance, with factor loadings ranging from 0.521 to 0.965. CFA confirmed the model, yielding acceptable fit indices: χ²/df = 2.947, RMSEA = 0.059, CFI = 0.954, NFI = 0.925 and GFI = 0.912. The overall Cronbach’s alpha was 0.94, while subscale reliability coefficients ranged from 0.83 to 0.92, demonstrating robust internal consistency across all analytical stages. CONCLUSION: The STISS is a psychometrically robust instrument for assessing stigmatising attitudes in STI care. Although it was initially validated within a student cohort, the scale’s clear factor structure and high reliability suggest that it is a suitable tool for identifying biases in infectious disease nursing. Further validation with diverse professional groups is recommended to enhance the scale’s generalisability. CLINICAL TRIAL NUMBER: Not applicable.