The performance measurement conundrum: Construct validity of the Individual Work Performance Questionnaire in South Africa

Abstract

Background: Performance remains high on the agenda of both researchers and practitioners, and rigorous measurement is central to evidence-based investigations. Several instruments have been developed to measure performance, of which one – the Individual Work Performance Questionnaire (IWPQ) – seems to be a scientifically rigorous instrument. Despite the growth in IWPQ validation studies, little is known about its psychometric properties in South Africa.

Aim: The current study seeks to address the construct validity of the IWPQ. The objective was to evaluate the construct (i.e. convergent, discriminant and nomological) validity of the instrument.

Setting: Information technology professionals were targeted in the current study, and the final sample consisted of 296 employees.

Method: Latent variable modelling was performed, using both independent cluster and exploratory structural equation model frameworks, with the mean- and variance-adjusted weighted least squares estimator. The analysis was complemented with the heterotrait-monotrait method.

Results: The results supported the construct validity of the instrument. Specifically, individual work performance was found to be a three-dimensional construct with acceptable convergent and discriminant validity. Job resources were also related to the three performance dimensions.

Conclusion: The factor structure of the IWPQ mirrors the factor structure found in the literature. Researchers and practitioners can use this instrument in South Africa to identify determinants and consequence of individual work performance, as well as to evaluate the effectiveness of performance improvement interventions.