Enhancing content validity assessment with item response theory modeling

Background: Ensuring the validity of assessments requires a thorough examination of the test content. Subject matter experts (SMEs) are commonly employed to evaluate the relevance, representativeness, and appropriateness of the items. This article proposes incorporating item response theory (IRT) in...

Descripción completa

Detalles Bibliográficos
Autores: Schames Kreitchmann, Rodrigo, Najera Álvarez, Pablo, Sanz Velasco, Susana, Sorrel Luján, Miguel Ángel
Tipo de recurso: artículo
Fecha de publicación:2024
País:España
Institución:Universidad Autónoma de Madrid
Repositorio:Biblos-e Archivo. Repositorio Institucional de la UAM
Idioma:inglés
OAI Identifier:oai:repositorio.uam.es:10486/719367
Acceso en línea:http://hdl.handle.net/10486/719367
https://dx.doi.org/10.7334/psicothema2023.208
Access Level:acceso abierto
Palabra clave:Content validity
item response theory
subject matter experts
test development
validity
Biología y Biomedicina / Biología
Descripción
Sumario:Background: Ensuring the validity of assessments requires a thorough examination of the test content. Subject matter experts (SMEs) are commonly employed to evaluate the relevance, representativeness, and appropriateness of the items. This article proposes incorporating item response theory (IRT) into model assessments conducted by SMEs. Using IRT allows for the estimation of discrimination and threshold parameters for each SME, providing evidence of their performance in differentiating relevant from irrelevant items, thus facilitating the detection of suboptimal SME performance while improving item relevance scores. Method: Use of IRT was compared to traditional validity indices (content validity index and Aiken’s V) in the evaluation of conscientiousness items. The aim was to assess the SMEs’ accuracy in identifying whether items were designed to measure conscientiousness or not, and predicting their factor loadings. Results: The IRT-based scores effectively identified conscientiousness items (R2 = 0.57) and accurately predicted their factor loadings (R2 = 0.45). These scores demonstrated incremental validity, explaining 11% more variance than Aiken’s V and up to 17% more than the content validity index. Conclusions: Modeling SME assessments with IRT improves item alignment and provides better predictions of factor loadings, enabling improvement of the content validity of measurement instruments