The group of 121 respondents consists of 65 medical staff and 56 medical engineers. Among the respondents, 27 were from the primary hospitals and 94 were from tertiary hospitals. The Pearson correlation coefficient between the observed and estimated preferences (the observed and predicted rank orders for the holdout profiles) was 0.875 and the Kendall’s tau was 0.662 (p < 0.001), showing the results were reliable and valid. Table 2 showed the utility values and attribute importance scores of endoscope after-sales service rated by different groups of respondents, i.e., medical staff, medical engineers and the whole population of both medical staff and medical engineers.
Table 2
Utility scores and attributed importance rated by respondents with different occupations
Attribute | Level | Medical staff | Medical engineers | Population |
Utility value | Attribute Importance (%) | Utility value | Attribute Importance (%) | Utility value | Attribute Importance (%) |
Service provision | 1. by the original manufacturer | 0.450 | 16.546 | 0.313 | 18.923 | 0.373 | 17.873 |
2. By third party service providers | -0.450 | -0.313 | -0.373 |
Maintenance quality | 1. Same fault ≤ 6 months | -2.811 | 22.612 | -2.601 | 21.811 | -2.694 | 22.165 |
2. 6 months < the same fault ≤ 12 months | -3.847 | -3.565 | -3.690 |
3. Same fault > 12 months | -3.106 | -2.894 | -2.988 |
Maintenance price | 1. Hard mirror ≤ 5000 yuan, soft mirror ≤ 10000 yuan | 1.774 | 20.396 | 1.011 | 21.408 | 1.348 | 20.961 |
2. Hard mirror ≤ 10000 yuan, soft mirror ≤ 30000 yuan | 2.469 | 1.416 | 1.881 |
3. Hard mirror ≤ 20000 yuan, soft mirror ≤ 50000 yuan | 2.087 | 1.215 | 1.600 |
Maintenance response | 1. Response ≤ 1 day | 1.547 | 24.328 | 1.519 | 23.141 | 1.531 | 23.665 |
2. 1 day < response ≤ 3 days | 2.392 | 2.280 | 2.329 |
3. 3 days < Response ≤ 7 days | 2.533 | 2.284 | 2.394 |
Maintenance efficiency | 1. Maintenance time ≤ 10 days | 1.226 | 16.118 | 1.071 | 14.717 | 1.140 | 15.336 |
2. 10 days ༜ maintenance time ≤ 20 days | 1.762 | 1.534 | 1.634 |
3. 20 days ༜ maintenance time ≤ 30 days | 1.606 | 1.388 | 1.484 |
Preferences of after-sale service of medical endoscope
Using equations (1)-(3), we obtained importance values of service attributes which reflected the hospitals’ awareness of the importance ranking of service attributes. According to the results of the conjoint analysis, the major factor influencing medical staff and engineers’ satisfaction on after-sales service is the “maintenance response"(23.665%), followed by "maintenance quality"(22.165%), “maintenance price”(20.961%), “service providers”(17.873%), and “maintenance efficiency” (15.336%), as shown in Table 2.
In Table 2, the utility values of the attribute level reflected the respondents' preference for the service selection. The greater the absolute value of the utility, the stronger the preference. The whole population’s preferences on endoscope after-sales services had the following features: for the attribute of "service provision”, there was a big difference between the two factor levels. There was a stronger preference on the "service provided by the original manufacturer" which received a utility value of 0.373, while the "service provided by the third party" received a negative utility value of − 0.373. It seems that medical staff and engineers were reluctant to use the third-party service providers. Under the attribute of “maintenance quality”, the utility values of the three factor levels were all negative, indicating that medical staff and engineers were not satisfied with the maintenance quality, regardless of the frequency of the same fault occurrence. Compared with the other two attribute levels, the medical staff and engineers were more willing to accept the moderate level of maintenance quality, i.e., 6 months ≤ same fault ≤ 12 months, as the absolute value of this attribute level is the highest (3.690). Regarding the attribute of "maintenance price", the utility values of the three factor levels were all positive, and the absolute values were relatively large, which showed that "maintenance price" was positively related to respondents’ preferences, and the correlation intensity was relatively high. The preference on the price level of "hard mirror ≤ 10,000 yuan, soft mirror ≤ 30,000 yuan" received the highest utility value of 1.881, showing that hospitals preferred to receive better maintenance services at the expense of a higher price. The attribute "maintenance response" had three levels of positive utility values, of which the utility value of "3 days < maintenance response ≤ 7 days" received the highest score of 2.394. This means that moderate maintenance response and receive maintenance response within 7 days was most describable. The attribute of "maintenance efficiency" also had three levels of positive utility values, of which the factor level "10 days < maintenance time ≤ 20 days" received the highest utility value of 1.634, showing that this level of efficiency was most desirable for medical staff and engineers.
Analysis of preferences on service profiles
Using the orthogonal design, 16 endoscope after-sales service profiles defined by 16 combinations of the attribute levels were evaluated, and the attribute important scores were obtained. The optimal results were derived from the conjoint analysis: the most desirable endoscope after-sales service profile was: "6 months ༜the same fault ≤ 12 months", "hard mirror ≤ 5000 yuan, soft mirror ≤ 10000 yuan", "response ≤ 1 day", "maintenance time ≤ 10 days" and "service provided by the original factory"; while the least favorable service profile was: "the same fault ≤ 6 months", "hard mirror ≤ 20000 yuan, soft mirror ≤ 50000 yuan", "3 days < response ≤ 7 days", "maintenance ≤ 20 days" and "the third party provides services". The results showed that response time, maintenance time, maintenance price and service providers were important to medical staff and engineers, who tent to choose the service provided by the original manufacturer, with quick response time, short maintenance time and low price. Compared with the other four attributes, a moderate level of maintenance quality (6 months ༜the same fault ≤ 12 months) was generally acceptable to the medical staff and engineers. This was attributed to the following reasons: medical endoscopes are operated in human body with a high frequency of use, and the operating environment is complex, therefore, there is usually a high fault or failure rate, with an average maintenance frequency of once per 12 months. The least favorable service profile was characterized by the "third party service providers" and poor "maintenance quality" ("the same fault ≤ 6 months"), which was consistent with the actual expectations on endoscope after-sales service, i.e., there was a strong resistance on the third-party post sales service and poor maintenance service.
Analysis of preferences by respondents with different occupations
Taking the occupation of respondents as a variable, we analysed and compared the relative importance of attributes, and factor utility values, rated by medical staff and medical engineers (see Table 2). The results showed that there was no significant difference existing in attribute importance or factor utility values between the two groups. The ranking of attribute importance was consistent between the two groups, showing that the selection preferences were identical in terms of service provision, maintenance quality, maintenance price, maintenance response, and maintenance efficiency. The utility values of factor levels varied between medical staff and engineers.
When choosing service provision, both groups preferred the service provided by the original manufacturer, but medical engineers felt that there was a small difference between the maintenance service provided by the original manufacturer and the service provided by the third-party provider, while medical staff thought that the difference was large. The different opinions were reflected in the utility values; 0.45 and − 0.45 were scored by medical staff, and 0.313 and − 0.313 were rated by engineers.
In terms of maintenance quality, both medical staff and engineers chose level 2, "6 months ༜ the same fault ≤ 12 months", but the utility values of this factor level was different.
Doctors and medical engineers both chose maintenance price level 2, i.e., "hard mirror ≤ 10000 yuan, soft mirror ≤ 30000 yuan”.
Both medical staff and engineers preferred the maintenance response level 3, i.e., "3 days < response ≤ 7 days", while medical engineers were also willing to accept level 2, i.e., "1 day < response ≤ 3 days". The scores assigned by medical engineers to levels 2 and 3 were 2.280 and 2.284, with a minor difference of 0.004. Medical staff rated levels 2 and 3 by 2.392 and 2.533, indicating that they were more inclined to accept level 3 rather than both levels 2 and 3. In addition, doctors and medical engineers were mroe willing to accept the maintenance efficiency level 2, i.e., "10 days ༜ maintenance ≤ 20 days". Both groups expected a high maintenance efficiency of endoscope after-sales service. The utility scores estimated from medical staff responses were higher than the utility values derived from engineers’ responses, which to an extent reflect the professional characteristics of different occupations hospitals.
Analysis of preferences by respondents from different medical institutions
Taking the type of medical institutions as a variable, we analysed and compared attribute importance, and utility values of factor levels, rated by respondents from primary hospitals and tertiary hospitals (as shown in Table 3). The two types of hospitals ranked the attributes in different orders: primary hospitals ranked the attributes as 1) maintenance response (the most important), 2) maintenance price, 3) maintenance quality, 4) service provision and 5) maintenance efficiency (the least important); while the ranking assigned by tertiary hospitals is: 1) maintenance response (the most important), 2) maintenance quality, 3) maintenance price, 4) service provision and 5) maintenance efficiency (the least important). The weight ranking of different attributes and the selection of each attribute level are also consistent. It was clear that maintenance price matters more to primary hospital than maintenance quality; while quality was more important to tertiary hospitals. The different focus was related to the overall strength and performances of different medical institutions. Primary hospitals usually had less investment in, or resources assigned to medical device services, hence, the maintenance quality was sacrificed as a trade-off to lower maintenance price. While tertiary hospitals’ overall performances and capabilities were stronger so that they could afford more expensive maintenance to ensure high maintenance quality. Although there was a difference in ranking attribute importance, the most desirable after-sales service profile chosen by primary hospitals and tertiary hospitals was identical, as defined by "service provided by the original factory", "6 months ༜ the same fault ≤ 12 months", "hard mirror ≤ 10000 yuan, soft mirror ≤ 30000 yuan", "response ≤ 7 days" and "7 days ༜ maintenance ≤ 20 days".
Table 3
Preference scores rated by respondence from different medical institutions
Variable | Level | Primary hospital | Tertiary hospital | Population |
Effect value | Weight(%) | Effect value | Weight(%) | Effect value | Weight(%) |
Service provision | 1. by the original manufacturer | 0.350 | 16.378 | 0.380 | 18.307 | 0.373 | 17.873 |
2. by third party service providers | -0.350 | -0.380 | -0.373 |
Maintenance quality | 1. Same fault ≤ 6 months | -2.639 | 20.399 | -2.710 | 22.678 | -2.694 | 22.165 |
2. 6 months < the same fault ≤ 12 months | -3.579 | -3.722 | -3.690 |
3. Same fault > 12 months | -2.819 | -3.036 | -2.988 |
Maintenance price | 1. Hard mirror ≤ 5000 yuan, soft mirror ≤ 10000 yuan | 1.620 | 21.479 | 1.269 | 20.811 | 1.348 | 20.961 |
2. Hard mirror ≤ 10000 yuan, soft mirror ≤ 30000 yuan | 2.181 | 1.794 | 1.881 |
3. Hard mirror ≤ 20000 yuan, soft mirror ≤ 50000 yuan | 1.681 | 1.577 | 1.600 |
Maintenance response | 1. Response ≤ 1 day | 1.250 | 26.946 | 1.613 | 22.713 | 1.531 | 23.665 |
2. 1 day < response ≤ 3 days | 1.958 | 2.437 | 2.329 |
3. 3 days < Response ≤ 7 days | 2.125 | 2.472 | 2.394 |
Maintenance efficiency | 1. Maintenance time ≤ 10 days | 0.880 | 14.799 | 1.215 | 15.492 | 1.140 | 15.336 |
2. 10 days ༜ maintenance time ≤ 20 days | 1.292 | 1.734 | 1.634 |
3. 20 days ༜ maintenance time ≤ 30 days | 1.236 | 1.556 | 1.484 |
Discussions
The influences of attributes on medical endoscope after-sales service
In the process of evaluating after-sales service of medical endoscopes, medical staff and engineers put stronger emphasis on two attributes, i.e., maintenance quality and maintenance response, and less attention was given to service provision, maintenance price and efficiency. Users of medical endoscopes, represented by medical staff and engineers in this research, paid more attention to the maintenance quality of medical endoscopes, and was not willing to accept the endoscope failure during use. They preferred to high maintenance quality to ensure less device failure in a short period of time, which would cause less disruption to medical diagnosis and treatment. Medical endoscopes are important and commonly used medical devices in the medical examination process; when a malfunction occurs, the users expect prompt responses from the after-sales service providers to resolve the problem, and to maintain continuity in examination and treatment.
Since public hospitals are non-profit institutions and benefit from partial financial subsidies from governments, they had the advantages of being able to afford high quality (with relative higher prices) medical endoscope after-sales service. They were not tolerant with low-price and low-quality after-sales service, nor were they interested in excessively expensive services.
Regarding the service provision, although “service provision” is a less important factor, the hospitals were resistant to "third party service providers". This is attributed to the poor standards the third-party service and the unreliable quality level. From the market perspectives, there is an expectation that the third-party service providers to provide fast response, flexible, customised support at competitive price, hence become the primary after-sales service providers [28, 29]. "Maintenance time" is least concerned. As a medical device, medical endoscopes require high maintenance quality, which takes a relatively long maintenance time. It took a long maintenance time to repair or maintain endoscopes and this was generally accepted, especially when the service providers could offer alternative endoscopes to use.
Medical staff and engineers have different preferences on after-sales service
Hospital workers were divided into medical staff and medical engineers, and there was no significant difference in the five attribute importance values rated by medical staff group and medical engineers group. Medical staff and medical engineers put strong emphasis on maintenance response, quality and price. Since medical staff was lack of knowledge on the causes or mechanisms to endoscope failures, as endoscope users, they needed prompt response from service providers, thereby to enhance their understanding of the impacts of the failure on the diagnosis/treatment, and to give them psychological support. Therefore, medical staff assigned higher preference scores to “maintenance response”. However, as providers of daily maintenance of medical endoscopes, medical engineers had a better understanding of the operation mechanism and working principle of endoscopes. When the medical endoscopes malfunctioned during use, they paid more attention to the causes of the malfunction, troubleshooting the problems and proposing solutions to fix the problems and avoid it in the future. With different emphasis and expectations on the after-sales service provision, medical engineers also assigned higher scores to maintenance response and maintenance quality. Furthermore, in the event of there being a failure of a endoscopes, medical engineers did not experience the same level of nervousness as medical staff, so they did not rate “maintenance response” as high as medical staff. On the contrary, medical staff, as users of endoscopes, did not understand the technical requirements of endoscope maintenance, so they believed the service provided by the original manufacturer was the best. Compared with medical engineers, medical staff assigned a higher score (0.450) to the service provision by the original manufacturer.
Primary hospitals and tertiary hospitals had different preferences on after-sales service
By analysing the attribute importance rated by respondents from different medical institutions, we found that “maintenance response” was the most important factor for both primary and tertiary hospitals. This is due to the similar reasons discussed above, which led to medical staff and medical engineers assign the highest score to this attribute.
With regards the second most important attribute, tertiary hospitals put more emphasis on "maintenance quality" while primary hospitals had more focus on "maintenance price”. It was related to the regional economic capacity, comprehensive strength of medical institutions and operation mechanism of medical institutions. In China, most hospitals are non-profit public organizations that are primarily funded by governments and generate revenue through service charges and medicine charges. In recent years, private medical institutions in China have developed rapidly, and some hospitals have further expanded in the form of groups and chains. In this study, it was observed that primary hospitals that rely on full funding from governments were more cautious in terms of operating expenses. This was reflected in the strong emphasis on "maintenance price”, which was higher than of the score rated by tertiary public hospitals. As a high-end medical equipment, medical endoscopes were widely used in higher level medical institutions, but less used in low-level medical institutions and private medical institutions was relatively low. Having a strong orientation towards low price endoscope maintenance service put the quality of maintenance at risk, which could lead to defective endoscopes used for diagnosis or examination. This is an important issue that is noteworthy and needs prompt actions. The segmentation of hospitals classified hospitals into different groups, for example, the primary and tertiary hospitals; general hospitals and specialist hospitals; public and private hospitals. Primary hospitals and private hospitals are more sensitive to the price factor, than tertiary and public hospitals. Considering the further opening of China's medical market and the vigorous development of private institutions, it can be predicted that demands on high-end and low-end medical products and services will continue to co-exist in China's medical market for a long time [30-33]. It is, therefore, imperative that medical product and service providers develop a wide portfolio of products and services, to meet hospitals’ diverse needs, and specifications for functions, features, service and price.
Selection and information bias
The experimental study design means that selection bias and information bias might exist, which is the limitation of this research. Selection bias could result from the selection of the respondents (subjects) in the conjoint analysis, which limits the comparability between groups (medical staff and medical engineers; primary and tertiary hospitals) being studied. To reduce the impacts of selection bias, the sampling method used in choosing respondents was random, and the professionals who met the criteria had equal probability to be included in the study. Future work will expand the conjoint analysis to include more subjects, and to further refine the conjoint analysis results.
The use of questionnaire is useful in collecting perspectives, views, and opinions on the preferences of endoscope service attributes. However, information bias may arise from self-reporting bias (such as recall bias), or inaccurate estimation. To overcome recall bias, we defined the selection criteria to choose respondents (subjects) to participate the questionnaire, requiring them having more than 3 years of experiences of using or managing medical endoscopes, therefore, these respondents were supposed to have up to date knowledge to evaluate the service attributes. To ensure internal validity of the collected responses and to minimise the impacts of inaccurate estimation, Pearson’s correlation coefficient and Kendall’s tau were calculated to check the reliability and validity of the regression model and estimated utility values.
The next phase of study will involve surveys with a wider group of respondents who will rate the service attributes. In additional to the use of statistical methods, we will compare the survey data and the results from conjoint analysis with Users’ Evaluation reports or Technical reports on medical endoscopes, to examine the validity and reliability of the self-reporting instrument.