2. LITERATURE REVIEW
Researchers believe that the service quality theory is based on the literature of customer satisfaction
and product quality (Brady & Cronin, 2001). There are many service quality models but scientists are not
of one mind about these models and measurements. Service quality has different dimensions regarding
the various service sectors (Pollack, 2009) Nevertheless, service quality measurement enables managers
to recognize quality problems and enhance the efficiency and quality of services to exceed expectations
and reach customer satisfaction.
Service quality perception wildly has been studied in last three decades. Zeithaml (1988) define service
quality as an assessment of customer from the overall excellence of service. It is because of service
quality nature, which is intangible, heterogeneous and inseparable. In recent decades, many models
have been developed for measuring service quality and the first attempt was by Gronroos in 1984. He
believes in distinguish between technical quality as an outcome for performance of service and
functional quality as a subjective perception of service delivered. Rust and Oliver have expanded
Gronroos model in 1994 by adding service environment as a new dimension.
In 1985 Parasuraman, Zeithaml, and Berry suggested the most used and famous model named
SERVQUAL. At first, they suggested ten dimensions for service quality but after some initial study in
1988, they reduced to five dimensions for service quality model. The SERVQUAL model was based on
difference between perception and expectation of quality of service through five dimensions.
Some researchers believe measuring the gap between expectation and perception, psychometrically
cannot obtain superior assessment of service quality. Hence, in 1992 Cronin and Taylor recommended
the SERVPERF model that was based on performance in service quality measurement. SERVPERF was
inclusive more of variance in overall service quality measurement than SERVQUAL. In addition,
Dobholkar, Thorpe, and Rentz in 1996 tested SERVQUAL and reported that this measurement has not
been adapted in some areas like retail store environment. They proposed a new model so called Retail
Service Quality Scale (RSQS). Brady and Cronin proposed Hierarchical and Multidimensional model for
service quality in 2001. They combined Rust and Oliver (1994) three components model and Dabholkar
et al. (1996) the multilevel model.