The purpose is to investigate, the difference between SERVQUAL and SERVPERF's predictive validity of service quality.
Data from 17 studies containing 42 effect sizes of the relationships between SERVQUAL or SERVPERF with overall service quality (OSQ) are meta‐analyzed.
Overall, SERVQUAL and SERVPERF are equally valid predictors of OSQ. Adapting the SERVQUAL scale to the measurement context improves its predictive validity; conversely, the predictive validity of SERVPERF is not improved by context adjustments. In addition, measures of services quality gain predictive validity when used in: less individualistic cultures, non‐English speaking countries, and industries with an intermediate level of customization (hotels, rental cars, or banks).
No study, that were using non‐adapted scales were conducted outside of the USA making it impossible to disentangle the impact of scale adaptation vs contextual differences on the moderating effect of language and culture. More comparative studies on the usage of adapted vs non‐adapted scales outside the USA are needed before settling this issue meta‐analytically.
SERVQUAL scales require to be adapted to the study context more so than SERVPERF. Owing to their equivalent predictive validity the choice between SERVQUAL or SERVPERF should be dictated by diagnostic purpose (SERVQUAL) vs a shorter instrument (SERVPERF).
Because of the high statistical power of meta‐analysis, these findings could be considered as a major step toward ending the debate whether SERVPERF is superior to SERVQUAL as an indicator of OSQ.
