|Prof. Parasuraman of Texas A&M univ.|
Parasuram et al proposed a method of how Gap 5 (the gap between customer perceptions and expectations which is a direct measure of the quality of service as experienced by the customer) can be measured quantitatively by asking a series of 22 questions relating to the 5 factors crucial in service - RATER - Reliability, Assurance, Tangibles, Empathy and Responsiveness .
Click for the original paper here from ResearchGate ..
Gap 1 - difference between what customer expects and what managements perceives are the customers expectations
Gap 2 - difference between what management perceives and the service design
Gap 3 - difference between service design and what service delivery
Gap 4 - difference between service delivery and what customer perceives as service
Gap 5 - difference between customer expectations and customer perception,
The 22 questions measuring instrument is given here ..
The basic premise for this quality instrument is the fact that service quality is directly proportional to customer satisfaction. Customer satisfaction is dependent on and directly proportional to the 5 factors of Reliability, Assurance, Tangibles, Empathy and Responsiveness (RATER) ..
The P-E score can be calculated for each of the 5 parameters. If for any of the factor, the P-E score is less, corrective actions can be initiated for those factors.
The P-E score is then taken for all 22 questions across the five factors and the average score for the total service delivery is calculated.
The total P-E score gives what the customer finally feels about the service.
If perceptions - expectations, (P-E), is positive, it is customer delight
If perceptions = expectations, (P=E), it is good service
If perceptions - expectations, (P-E), is negative, it is deficient service
Comparison between Net Promoter score and SERVQUAL :
While Net Promoter Score does not differentiate between the different factors and instead just gives only an overall final score of what the customer feels about the service, SERVQUAL instrument gives the gap between customer perception and expectation across the five factors, RATER.SERVQUAL thus helps us to understand exactly in which of the above factors is the service deficient and one can then take necessary steps to understand the deficiency in those factor areas and take corrective steps to overcome it.
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