It is important to have a measure that can be used to reliably measure beliefs and attitudes about the dentist. Therefore, the aims of our study were to (1) translate the DBS-R into Standard Mandarin and (2) explore the reliability and validity of this newly-translated measure (both long and short-form) in a Chinese sample.
Across the sample, the psychometric properties for both the short and long version of the CDBS-R were found to be similar. Both versions had good reliability and validity. The internal consistency of the Chinese DBS-R was tested using the Cronbach’s alpha coefficient, and it demonstrated a high level of internal consistency in both versions (0.93 – 0.94). These are comparable to alpha levels found in other studies for both clinical and non-clinical samples1,2,4,12. In addition, when we calculated the Cronbach’s Alpha for the subscales of the DBS-R they are all internally consistent though slightly lower values were noted on the shorter form (0.73-0.86 short vs 0.84-0.90 long versions). Thus, our findings show that the items on the CDBS-R measure a single underlying construct for both the long and short versions. Test-retest data demonstrated that the CDBS-R is stable over time (in this instance across a two-week period). Thus the reliability of the CDBS-R in our sample is also evidence that its underlying constructs are stable outside of the dental setting. This is particularly pertinent considering the high number of adults in our sample that are never-attenders. It would now also be useful to test the CDBS-R also in a clinical population.
The weak to moderate but significant correlation between the Modified Dental Anxiety Scale (MDAS) and CDBS-R also indicates that the two scales are tapping somewhat similar, but not identical, underlying constructs. For example, it might be possible for individuals to be highly fearful of certain dental procedures, assessed by the MDAS, but not necessarily to have negative beliefs about the dentist, assessed by the CDBS-R. A similar finding was reported in the validation study for the Spanish version of the DBS-R4. Moreover, as an additional test of validity, when we divide the participants into high and low anxiety groups based on an established cut-off, as predicted we find that scores on the CDBS-R are significantly different, with the highly anxious group having more negative dental perceptions.
Higher scores on the CDBS-R indicate greater negative perceptions of dentists and the dental visit. The mean overall score for the CDBS-R appears high (85.2 for the long form and 72.7 for the shorter form), especially when compared to studies conducted in Western countries. For example, Coolidge et al1, in their psychometric evaluation of both forms of the English version of the DBS-R, the mean score in their American student sample was 51.5 and 46.6 for the longer and shorter-form. Moreover, in a non-clinical study using the 28-item Spanish version of the DBS-R with a Spanish-speaking community sample of Hispanics in the USA the mean was 61.24. In addition, perceptions of the dentist in our Chinese participants were consistently negative across all of the sub-scales on the DBS-R (mean item scores were between 2.97 and 3.10). Abrahamsson et al2 compared item mean scores between students (1.7- 2.3), general dental patients (1.4 - 1.8), periodontal patients (1.6 - 2) and fearful dental patients (2.7 – 3.6). Thus, in comparison our Chinese sample have beliefs most in line with fearful dental patients. Although a cross-cultural study would be needed in order to explore this fully, this appears to indicate that beliefs about dentists in our Chinese sample may be more negative than found in some Western countries.
In our sample, there were differences across the sub-scales in terms of mean item total scores. For the 28-item version, participants had significantly higher mean item totals on the Professionalism/Ethics sub-scale than the Communication and the Control sub-scales. On the 24-item version there was also a significant difference in item mean scores with participants having higher mean item totals on the Ethics sub-scale compared to the other three sub-scales. This would appear to indicate that Professionalism/Ethics of dentists are viewed most negatively by participants, and this is a finding that is not commonly reported in studies utilising the DBS-R. There are overlapping items in terms of the Professionalism/Ethics and Ethics sub-scales across the two scales in that they both include items pertaining to concerns about the dentist providing the necessary information, having the patient’s best interests at heart and carrying out work that is not necessary. Our findings in relation to professionalism and ethics may, in part, be linked with the oral health services in China. Dental care is offered only on a fee-for-service basis and is expensive to access, even though care is primarily provided by the public health service based in hospitals. Although there are private dental practices, insurance does not reimburse for treatment and it is much more expensive than the public health alternative. Thus dental care is expensive across sectors. It may be that this contributes to a belief that dentists perform treatment that is expensive and not always necessary. However, this is speculative, and does not fully explain negative perceptions across other factors included in this dimension e.g., how dentists handle information (such as, withholding information and not giving clear explanations). There is a need for further work, possibly of a qualitative nature, to fully explore these beliefs in the Chinese culture.
Interestingly, Kvale et al12 in the 24-item DBS-R, omitted several items from the Professionalism/Ethics sub-scale that relate to the technical competence of the dentist. ‘I worry if the dentist is technically competent and is doing quality work’ and ‘I’m concerned that dentists might not be skilled enough to deal with my fear or dental problems’ were removed as these items were not considered directly relevant to the interpersonal relationship. However, in our sample these items scored highly - Item 3 which is related to competency/skilled work was the highest scoring item. This may indicate two things. First, that technical competency and skill are important issues when viewing dentists in China (for those who have and have not been a dental patient), and as such should be explored further. Second, since only the 28-item CDBS-R includes these items, this may be the scale of choice when assessing perceptions of the dentist in a non-clinical Chinese sample.
Mean item totals were higher on the Control subscale than the Communication subscale only on the 28-item scale and this is similar to other studies. For example, in Abrahamsson et al’s study2 they found that the Control sub-scale had the highest mean item total (across both the 24 and 28 item versions) and in both clinical and non-clinical groups. As Abrahamsson and colleagues highlight, these feelings should be acknowledged and strategies put in place to increase patients feeling more in control.
In our sample, there were low rates of regular dental attendance and twenty-two percent of the participants reported that they had never been to the dentist. Though we should acknowledge that these are based on self-report, these findings concur with previous (though sparse) research exploring dental service utilization in China. It has been noted that the number of dental practitioners is low relative to population and though the numbers of dentists have grown rapidly in recent years, dental service utilization remains low17. Zhu et al18 reported on the third oral health national survey including oral health practices, behavior, knowledge and attitudes. Twenty-two percent of the respondents had never visited a dentist. Moreover, dental attendance in the last 12 months from the fourth, and most recent, national survey (2015 – 2016) showed that only twenty percent of adults surveyed reported attending the dentist in the past year19. Within our pilot study, the high number of ‘never attenders’ was also acknowledged during the pilot stage of our study (7 out of 35 had never attended). Thus the instructions on the Chinese DBS-R were slightly modified in order to reflect this. It was deemed important to do this, so that items ‘made sense’ to all participants – not just those who had visited a dentist. We would argue that it is as important to assess the perceptions of those who have never attended, as it is to assess those who have. Indeed, perceptions of the behaviour and attitude of dentists can affect dental anxiety and could influence the decision to access dental care – this could be irregularly or not at all. When we compared total CDBS-R scores between those who had never attended the dentist and those who had – those who had never attended had more negative perceptions of the dentist and this difference was significant. This provides further evidence of validity but also indicates that there is a need to assess and address (and further explore the possible underlying reasons for) the negative perceptions of these non-attenders to hopefully also help facilitate accessing dental care.
It is important to acknowledge the strengths and limitations of our study. In terms of strengths, we followed a rigorous translation method (forwards-backwards method). We also piloted the measure which was an important step to ensure that the measure was understandable for Chinese individuals. We also tried to ensure that the same meaning was conveyed on the translated measure while at the same time making the Chinese version culturally meaningful. In terms of limitations, although we sampled from three provinces, and aimed to get a varied sample in terms of demographics and experience, we still had a relatively high number of students in our sample, so cannot purport to generalise across the whole of China. In addition, there was an over-representation of females in our sample. However, it should be noted that across countries females do appear to take part in studies on dental-related beliefs and dental-related fear more often than males, and as such there is an over-representation of females in study samples across both clinical and non-clinical samples2, 20-22.