Using item response theory to develop and test a realistic vocational interest scale

An 11-item scale developed with Item Response Theory (IRT) showed strong internal consistency and greater measurement information than two existing instruments for assessing realistic vocational interest among middle-school students. Researchers Pengjuan Zhao, Xuliang Gao and Chuanji Wang analyzed data from 1,248 middle-school students and finalized the Realistic Interest Scale-11 (RIS-11) after evaluating its dimensionality, monotonicity, local independence and item fit. Their analysis included Item Characteristic Curves and Information Functions, which were used to examine the behavior of the questions and the measurement information supplied by the scale.

Based on these evaluations, the researchers selected 11 items for the final short form. The RIS-11 achieved a Cronbach’s alpha of 0.960, indicating high internal consistency reliability in the sample studied. The article describes the scale as reliable and psychometrically sound within the cultural context in which it was developed, while the study specifically examined middle-school students rather than a broader population.

The researchers compared the RIS-11 with the Realistic subscale of the Chinese version of Holland’s RIASEC and the practical-operations-interest subscale of Su’s SETPOINT model. Comparative analyses showed that the RIS-11 provided greater informational value than both comparators. This comparison concerns the measurement information generated by the instruments in the study; the supplied evidence does not establish that the scale is superior for career guidance or that its scores predict later educational or occupational choices.

The open-access research was published in BMC Psychology on 16 September 2026. The publisher’s notice states that the accessible version is an early, peer-reviewed and citable record of accepted research and may be replaced by the final Version of Record after further edits. The results therefore describe the development and testing of RIS-11 in the analyzed sample of 1,248 middle-school students, rather than demonstrating that the same performance will hold in every school, region or population.

Subject of Research: Psychometric development of an 11-item realistic vocational interest scale for middle-school students using Item Response Theory.

Article Title: Using item response theory to develop and test a realistic vocational interest scale

Article References: Zhao, P., Gao, X., & Wang, C. (2026). Using item response theory to develop and test a realistic vocational interest scale. BMC Psychology. https://doi.org/10.1186/s40359-026-05584-1

Image Credits: AI Generated

DOI: 10.1186/s40359-026-05584-1

Keywords: item response theory, vocational interest, scale development, psychometrics, middle-school students, graded response model, measurement information, realistic interest, risk assessment, item, response, theory