Measuring internal service
quality: comparing the gap-based
and perceptions-only approaches
Bath School of Management, University of Bath, Bath, UK, and
Warwick Business School, University of Warwick, Coventry, UK
Purpose – This paper aims to build upon the debate in the service quality literature regarding both
the theoretical and practical effectiveness of expectations data in the measurement of internal service
quality (ISQ). Gap-based and perceptions-only approaches to measuring ISQ are tested and their
respective beneﬁts and limitations evaluated.
Design/methodology/approach – The internal service context used in this study is the provision
of e-procurement software, training, and user support in four organisations. The two approaches are
evaluated in terms of reliability and validity, as well as pragmatic aspects of survey administration.
Findings – The various tests carried out indicate that both the gap-measure and perceptions-only
measure are reliable and valid, the latter being the marginally higher performer. Both approaches were
found to have beneﬁts and limitations, and so the empirical study, combined with contributions from the
literature, generates some understanding of the internal service context in which the two approaches
might be appropriate.
Research limitations/implications – The survey wasbased on an internal e-procurement service; as
such, the variables and dimensions selected to measure ISQ in this context inevitably limit the scope of the
Practical implications – For operations managers, the paper clariﬁes the basis on which they might
choose between the two approaches to ISQ measurement.
Originality/value – This study is the ﬁrst to directly test and compare the relative merits of these
two approaches to ISQ measurement. The paper also offers insights as to the operational contexts in
which each approach might be appropriate.
Keywords Customer services quality, Service quality assurance, Quality assessment, SERVQUAL,
Paper type Research paper
The management of internal service quality (ISQ) can be traced back to Ishikawa’s
concept of the voice of the customer (1985) and has been an emerging theme in the service
operations and marketing literature over the past two decades (George, 1990; Davis,
1991; Stauss, 1995; Ahmed and Raﬁq, 2000). ISQ is deﬁned as the perceived quality of
service provided by distinctive organisational units or the people working in these,
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The authors wish to thank all those who participated in this research project. In addition, they
would like to express their gratitude to the editors and reviewers for the time and effort they gave
in reviewing this paper. The feedback provided was extremely useful in improving the work.
Received January 2009
Revised September 2009,
Accepted April 2010
International Journal of Operations &
Vol. 30 No. 12, 2010
q Emerald Group Publishing Limited