A newly developed 18-item psychometric assessment, the Clinical Contraceptive Knowledge Test (CCKT-18), demonstrated strong initial validity, reliability, and structural robustness for assessing contraceptive knowledge among undergraduate medical students in Vietnam. In a cross-sectional multicenter study, researchers evaluated the instrument using item response theory, finding that a unidimensional two-parameter logistic model showed good fit to the data with a Comparative Fit Index of 0.983, Tucker-Lewis Index of 0.980, Root Mean Square Error of Approximation of 0.036, and Standardized Root Mean Squared Residual of 0.039. The unidimensional structure was retained based on comparable fit to multidimensional models and high inter-factor correlations exceeding 0.80.
The research addressed ongoing challenges in accurately measuring contraceptive knowledge among medical trainees arising from limitations in traditional assessment instruments. The multi-phase development process encompassed four sequential stages: initial item generation grounded in Bloom’s taxonomy and the World Health Organization Medical Eligibility Criteria, expert panel review for content validity, preliminary pilot testing under Classical Test Theory, and large-scale validation applying item response theory. The multicenter investigation recruited 723 undergraduate medical students across Vietnam, with 636 participants retained in the final analytical sample to evaluate item characteristics, dimensionality, and measurement precision.
The resulting scale achieved high measurement precision across a broad spectrum of student ability levels, exhibiting peak information around the average proficiency level with a marginal reliability of 0.844. Sensitivity analyses confirmed structural robustness, as item parameters and overall model fit remained stable with a delta CFI of 0.003. While differential item functioning analyses demonstrated measurement invariance across sex, several items showed differential item functioning across participants’ training stages. The authors concluded that the instrument’s framework provides precise, competency-oriented evaluation and actionable insights for targeted curriculum improvements in reproductive health education.
Subject of Research: Validation of the Clinical Contraceptive Knowledge Test among Vietnamese medical students
Article Title: Measuring what future physicians know about contraception: development and validation of the clinical contraceptive knowledge test (CCKT) in Vietnam using item response theory
Article References: Ky, N. D., Anh, N. Q., Minh, N. N., Lam, P. T., Cham, D. T. H., Linh, T. K., Chi, N. D. L., Anh, P. H., Hanh, N. T. H., Nguyen-Tien, T., Anh, N. T. H., & Thang, N. M. (2026). Measuring what future physicians know about contraception: development and validation of the clinical contraceptive knowledge test (CCKT) in Vietnam using item response theory. Contraception and Reproductive Medicine. https://doi.org/10.1186/s40834-026-00488-2
Image Credits: AI Generated
DOI: 10.1186/s40834-026-00488-2
Keywords: contraceptive knowledge, medical students, item response theory, psychometrics, Vietnam, reproductive health education, CCKT-18, medical education, Measuring, future, physicians, know
News Source: Ophelia Keating. (November 5, 2026). New Clinical Contraceptive Knowledge Test Validated for Medical Students in Vietnam. Scienmag.
