SERVQUAL Outgrew Its Originators: A Bibliometric and Conceptual Analysis of Four Decades of Research, 1985–2025

Preprint. SERVQUAL was proposed as an instrument for measuring perceived service quality, and four decades later it is cited more often as a model than used as a scale. This study maps how the concept has been used across 1985–2025 and reads the resulting structure through the lens of concept analysis. All 3,746 Scopus records that mention SERVQUAL in their title, abstract, or keywords were retrieved on November 1, 2026, with a single reproducible query, and analyzed with the R package bibliometrix and a documented script. Thematic evolution across four periods (1985–1994, 1995–2004, 2005–2014, 2015–2025), local and global citation structures, a historiograph, a title-only subset, and keyword-based application domains were examined. The literature grew from 31 records in the first period to 2,418 in the last; the United States led until 2004, after which China, India, Indonesia, Iran, and Malaysia became the main sources of corresponding authors. Themes moved from application sectors (health care, higher education, tourism) in 1995–2004 to outcome concepts (customer satisfaction, quality) in 2005–2014 and then split into dimension-level and derivative themes (reliability, patient satisfaction, e-servqual, servqual model) in 2015–2025. Health care is the largest application domain throughout and regained share in the last period. The founding papers of 1985, 1988, and 1991 are absent from Scopus as records but are the most cited references within the corpus, and the two reviews of 1996 and 2009 are the most cited records. Read with the elements of concept analysis proposed in nursing (defining attributes, antecedents, consequences, related concepts), the trajectory shows a concept whose attributes stabilized early, whose consequences became its dominant research question, and whose related concepts multiplied beyond its authors' own revisions. This paper is a revised and extended version of "SERVQUAL Research Trends of the Past Decade: A Bibliometric Review of Themes and Structural Elements" (SSRN, 2025; archived at https://doi.org/10.5281/zenodo.23852069). The analysis script and output tables are at https://doi.org/10.5281/zenodo.23851891.