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Development of a Dental Anxiety Provoking Scale: A pilot study in Hong Kong
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Journal of Dental Sciences (2015) xx, 1e8
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ORIGINAL ARTICLE
Development of a dental anxiety provoking scale: A pilot study in Hong Kong Hai Ming Wong a*, Cheuk Ming Mak b, Wai Ming To c a
Department of Paediatric Dentistry and Orthodontics, Faculty of Dentistry, the University of Hong Kong, Hong Kong b Department of Building Services Engineering, the Hong Kong Polytechnic University, Hong Kong c School of Business, Macao Polytechnic Institute, Macao, China Received 22 May 2014; Final revision received 29 August 2014
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KEYWORDS dental anxieties; pilot study; test anxiety scale
Abstract Background/purpose: Dental anxiety is closely related to one’s past experience in dental clinics. However, little is known about what clinical, environmental, and psychological aspects provoke anxiety in dental patients. Extending on previous work in The Netherlands which explored anxiety provoking stimuli, the objective of the study was to develop a Dental Anxiety Provoking Scale (DAPS) that measures the degree to which anxiety was provoked by dental stimuli and to identify the underlying factor structure of the DAPS. Materials and methods: Four hundred and sixty study participants were recruited from two universities in Hong Kong. Each participant completed a self-administrated questionnaire that included a 73-item measure of dental anxiety provoking stimuli, and a four-item dental anxiety scale. Results: Results of exploratory and confirmatory factor analyses showed that the DAPS has seven factors, namely, dental check-up, injection, scale and drill, surgery, empathy, perceived lack of control, and clinic environment, and has 27 items. Results of structural equation modeling showed that three factors of the DAPS; dental check-up, surgery, and clinic environment, had a significant effect on dental anxiety score. The Cronbach a values ranged from 0.76 to 0.92 while the composite reliability values ranged from 0.78 to 0.93. The average variance extracted (AVE) values ranged from 0.55 to 0.81. The minimum AVE value was greater than the square of correlation value for each pair of factors. Conclusion: The study developed and validated the DAPS covering a wide range of dental anxiety provoking stimuli, findings were concise enough to be used in clinical based studies. Copyright ª 2015, Association for Dental Sciences of the Republic of China. Published by Elsevier Taiwan LLC. All rights reserved.
* Corresponding author. Department of Paediatric Dentistry and Orthodontics, Faculty of Dentistry, the University of Hong Kong, 2/F Prince Philip Dental Hospital, 34 Hospital Road, Hong Kong. E-mail address: [email protected] (H.M. Wong). http://dx.doi.org/10.1016/j.jds.2014.09.003 1991-7902/Copyright ª 2015, Association for Dental Sciences of the Republic of China. Published by Elsevier Taiwan LLC. All rights reserved.
Please cite this article in press as: Wong HM, et al., Development of a dental anxiety provoking scale: A pilot study in Hong Kong, Journal of Dental Sciences (2015), http://dx.doi.org/10.1016/j.jds.2014.09.003
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H.M. Wong et al
Introduction
Materials and methods
Dental anxiety has been a research focus over the past several decades.1e9 Despite the advances in dental equipment and procedures, dental anxiety is still recognized as a major issue in the provision of dental care.2,3,5e10 Patients with high dental anxiety recall more pain than they actually experienced in tooth extraction.11 Empirical evidence demonstrated that a high level of dental anxiety was significantly associated with irregular dental attendance,12,13 delays in dental treatment,10 and dental avoidance.14,15 Armfield et al10 reported that high dental anxiety was related to less frequent dental visits, more severe dental problems, and only visiting dental clinics for painful dental problems. Hence, high dental anxiety is significantly associated with poor oral health.5,10 In addition, it was found that parents’ dental anxiety and avoidance behaviors were related to dental caries in children.15 Hence the vicious cycle of dental anxiety not only affects a person’s oral health but may also affect the person’s next of kin. The existing literature has put a lot of emphasis on the consequences of dental anxiety. However, the current study examines what causes dental anxiety. Although dental anxiety is shown to be closely related to one’s past experience in dental clinics,16e18 the provoking effect of clinical and environmental aspects on the anxiety of dental patients has yet to be comprehensively studied. Oosterink et al16 conducted an extensive literature review and found that most literature focused on certain aspects of anxiety provoking stimuli and practices in the dental setting. The most common aspects include pain sensations,19,20 having dental surgery,21 having an injection,22,23 sight, sound, and feeling of the drill,12,19,24 negative dentist behavior,25 various aspects of clinical environment such as the sight and sound of dental chair and equipment,12 the smell of the clinic,18,24,26 and perceived lack of control.18,26 Oosterink et al16 compiled a questionnaire that covered 67 potentially anxiety provoking stimuli in the dental setting and tested the questionnaire using a convenience sample in The Netherlands. They aimed to establish a hierarchy of anxiety provoking stimuli. Using the Scree plot of eigenvalues from the exploratory factor analysis they found that stimuli could be categorized by two sets of factors: (1) invasivetreatment-related stimuli factors; and (2) noninvasivetreatment-related stimuli factors. Oosterink et al16 showed that the number of extreme anxiety-provoking stimuli had the greatest influence on the dental anxiety score (DAS) using stepwise regression analysis. However, Oosterink et al16 did not continue to investigate the factor structure of those stimuli in detail and did not establish the relationships between anxiety provoking stimuli factors and DAS. The current study addresses these gaps in dental research by establishing a Dental Anxiety Provoking Scale (DAPS) and examining the relationship between DAPS and dental anxiety. The developed DAPS is more concise and better suited for clinical use. This study followed established procedures for scale development in social science starting with identification of an item pool, checking the face and content validity of the items, collecting data, performing exploratory and confirmatory factor analyses, and ending with assessing external validity of the scale.
Participants A convenience sample of university students in Hong Kong was recruited from the University of Hong Kong (250 students) and the Hong Kong Polytechnic University (400 students). Out of the sample of 650 students, 460 students (230 students from each university) completed and returned questionnaires, representing a response rate of 71%. All of the participants had dental experience as free dental check-ups and treatment are provided in the universities, and 95% of school children join the School Dental Care Service provided by the Department of Health, Government of Hong Kong Special Administrative Region. University students were selected because they have the language ability to respond to an English questionnaire and they can articulate their experiences in the dental setting. The problems inherent in translation were avoided. Out of the 460 respondents, 230 (50%) were female. The largest group of respondents were aged 20e21 years (n Z 160), followed by 22e23 years (n Z 140), 18e19 years (n Z 120), < 18 years (n Z 20), and 24 years (n Z 20). It should be noted that the use of students as study participants may threaten the generalizability of the study findings due to the unique characteristics of the student population.
Data collection Ethical approval was obtained from the Institutional Review Board of the University of Hong Kong/Hospital Authority Hong Kong West Cluster (UW 14e010). Teaching assistants invited students who attended lectures and tutorials in various faculties to participate. Participation was voluntary and selfadministered anonymous questionnaires were used to collect data. Informed consent was obtained from all participants. Teaching assistants distributed the questionnaires in the classroom and participants were asked to return the questionnaires in 15 minutes, before lectures/tutorials began.
Instrument: Dental anxiety provoking stimuli This list contains 73 items covering a wide range of situations and stimuli that provoke a person’s anxiety toward dentistry. The stimuli include the 67 potential anxiety provoking stimuli adopted from Oosterink et al16 and the following six items proposed by the authors: (1) sight of the scaler; (2) the smell when scaling teeth; (3) the taste when scaling teeth; (4) the sound of scaling teeth; (5) sensation of the active scaler; and (6) the taste when drilling teeth. The items were reviewed by two faculty members and 10 students in the Faculty of Dentistry to ensure face and content validity.27,28 All items were rated on a 4-point Likert scale ranging from 1, representing not anxiety provoking at all, to 4, representing extremely anxiety provoking.
Instrument: Dental anxiety scale (DAS) DAS is a four-item measure designed to assess a person’s anxiety toward dentistry. The scale was developed by
Please cite this article in press as: Wong HM, et al., Development of a dental anxiety provoking scale: A pilot study in Hong Kong, Journal of Dental Sciences (2015), http://dx.doi.org/10.1016/j.jds.2014.09.003
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Development of a dental anxiety provoking scale
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Corah1 and has been the most widely used measure in dental anxiety studies.29 The participant is asked to imagine her/himself in four different dental situations and to rate how she/he feels, from “reasonably enjoyable/ relaxed” to “very frightened/almost feel physically sick”. High scores indicate high dental anxiety. The Cronbach a values of the DAS were 0.89 and 0.86 in a study by Eli et al.4
analysis (CFA) was performed on the second group of samples using structural equation modeling to further investigate the stability and validity of the scale identified in EFA.
Results Exploratory factor analysis
Statistical analysis
Based on the initial 73-item measure, Bartlett’s test of sphericity was found to be significant (c2 Z 10,685; df Z 2,628; P < 0.001) and the Kaiser-Meyer-Olkin measure of sampling adequacy was 0.94. These results suggested that the correlation matrix was not an identity matrix and the inter-correlation matrix contained enough common variance to make factor analysis worthwhile. The EFA was then performed using principal components analysis with varimax rotation. By deleting items with loadings < 0.6 and cross-loading > 0.4 iteratively, a seven-factor structure of DAPS that explained 71.3% of the variance of the measures was identified. The identified seven factors are injection (4 items), surgery (3 items), scale and drill (3 items), perceived lack of control (4 items), empathy (3 items), environment (3 items), and dental check-up (7 items). Table 1 shows descriptive statistics, reliability estimates (Cronbach a values), and bivariate correlations among the identified variables using the first group of samples (n Z 160; 74 females and 86 males). In general terms, this
The collected data were coded and analyzed using SPSS version 17.0 and AMOS 17.0 (SPSS Inc., Chicago, IL, USA). Following established procedures for scale development28 the data were randomly split into two groups: 160 for the first group and the remaining 300 for the second group. Chisquare tests and independent t tests were performed. Results showed that there was no statistically significant difference in demographic data and item scores between the two groups and the whole sample. Exploratory factor analysis (EFA) was performed on the first group of samples to identify factor structures using principal component analysis with varimax rotation. The latent root criterion and a scree plot were used simultaneously to determine the number of factors. Items with loadings < 0.6 and crossloading > 0.4 on more than one factor were deleted iteratively. The results from the EFA would yield theoretically meaningful, interpretable factors. Confirmatory factor
Table 1 Descriptive statistics, reliability estimates, and bivariate correlations between the variables identified in exploratory factor analysis and dental anxiety scale (DAS) scores (N Z 160; 74 females and 86 males). Factor
No. of items
Mean (SD)
a
1
(1) Injection Female subgroup Male subgroup (2)Surgery Female subgroup Male subgroup (3)Perceived lack of control Female subgroup Male subgroup (4)Empathy Female subgroup Male subgroup (5)Scale and drill Female subgroup Male subgroup (6)Environment Female subgroup Male subgroup (7)Dental check-up Female subgroup Male subgroup DAS (Total score) Female subgroup Male subgroup
4
2.68 2.71 2.64 2.61 2.66 2.57 2.33
(0.88) (0.82) (0.93) (0.92) (0.90) (0.95) (0.82)
0.89
1.00
0.84
0.51
1.00
0.89
0.42
0.48
1.00
2.29 2.36 2.32 2.28 2.35 1.95 2.02 1.88 1.71 1.74 1.68 1.59 1.52 1.65 8.57 8.97 8.38
(0.82) (0.83) (0.77) (0.75) (0.78) (0.81) (0.87) (0.77) (0.77) (0.85) (0.70) (0.64) (0.62) (0.65) (3.30) (3.10) (3.46)
0.83
0.36
0.43
0.51
1.00
0.87
0.52
0.47
0.35
0.37
1.00
0.90
0.38
0.38
0.26
0.28
0.61
1.00
0.91
0.32
0.34
0.27
0.36
0.58
0.63
1.00
0.85
0.39
0.48
0.35
0.28
0.59
0.61
0.49
3
4
3
3
3
7
4
2
3
4
5
6
7
SD Z standard deviation.
Please cite this article in press as: Wong HM, et al., Development of a dental anxiety provoking scale: A pilot study in Hong Kong, Journal of Dental Sciences (2015), http://dx.doi.org/10.1016/j.jds.2014.09.003
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4 group of respondents indicated that perceptions of injection [mean (M) Z 2.68, standard deviation (SD) Z 0.88] and surgery (M Z 2.61, SD Z 0.92) are anxiety-provoking events and showed moderate levels of dental anxiety (M Z 8.66, SD Z 3.30). Among the 160 respondents, 20 (12.5%) were classified as dentally anxious individuals because they had a DAS score of 13 or more.30 The Cronbach a values ranged from 0.83 to 0.91, all greater than the threshold of 0.7 for internal consistency.31 Female respondents showed a relatively higher anxiety toward injection, surgery, scale and drill, and environment while male respondents showed a relatively higher anxiety toward perceived lack of control, empathy, and dental check-up as shown in Table 1. However, independent t tests showed that the differences between females and males on the seven identified factors and the DAS were too small to be significant. The seven factors and the associated 27 items identified are given in Appendix 1.
Confirmatory factor analysis CFA was applied to the data from the second group of samples i.e. 300 respondents. The CFA results confirmed the seven-factor structure identified in the EFA as an acceptable structure. Fig. 1 shows the factor structure of the CFA model. The fit indices of this measurement model were: c2/df Z 2.16 (c2 Z 655.6; df Z 303), goodness of fit index (GFI) Z 0.86, comparative fit index (CFI) Z 0.93, root mean square residual (RMSR) Z 0.04, and root mean square error of approximation (RMSEA) Z 0.06 in which GFI and CFI were >0.85 (i.e., acceptable) and 0.90 (i.e., good), RMSR and RMSEA were <0.08, respectively.32,33 The average variance extracted (AVE) was computed using standardized loadings. The measurement errors and AVE were used to assess the convergent validity and the discriminant validity of the factors. Table 2 shows descriptive statistics, reliability estimates including Cronbach a values, composite reliability (CR) and AVE values, inter-correlations of the seven factors, and DAS. This group of respondents indicated that perceptions of injection (M Z 2.85, SD Z 0.79) and surgery (M Z 2.71, SD Z 0.88) are anxiety-provoking events and showed moderate levels of dental anxiety (M Z 9.07, SD Z 3.28). Independent t tests showed that there were no significant differences between the second group of respondents and the first group of respondents. Among the 300 respondents, 45 (15%) were classified as dentally anxious individuals because they had a DAS score of 13. In this group of respondents, females showed a relatively higher anxiety toward the identified seven factors and had a relatively higher DAS score (Table 2). However, independent t tests showed that the differences between females and males on all factors and DAS were too small to be significant. The Cronbach a values ranged from 0.76 to 0.92 while the CR values ranged from 0.78 to 0.93, suggesting that the factors have high internal reliability. The AVE values ranged from 0.55 to 0.81. These values were greater than the threshold of 0.5, suggesting that each factor has adequate convergent validity and measures its intended concept.34 Discriminant validity, i.e., the degree to which factors are distinct, was assessed by comparing the minimum AVE value
H.M. Wong et al for each pair of factors with the square of the correlation between two factors. The minimum AVE value was greater than the square of the correlation value for each pair of factors, indicating good discriminant validity. The predictive validity of DAPS was assessed by using structural equation modeling (SEM). In this case, DAS was employed as the outcome variable while the seven factors were treated as independent variables. The structural model showed that three factors including surgery, environment, and dental check-up had significant effects on DAS. The path estimates between surgery and DAS, environment and DAS, and dental check-up were 0.44, 0.30, and 0.21, respectively. The results indicated that a person’s perception of surgical treatment strongly and significantly provoked anxiety, followed by perception of getting into the dental office and lying in the dental chair (i.e., clinic environment), and a general perception of having a dental check-up. The fit indices of this structural model were: c2/ df Z 2.10 (c2 Z 860.5; df Z 410), GFI Z 0.85, CFI Z 0.93, RMSR Z 0.05, and RMSEA Z 0.06, suggesting that the structural model fitted the data appropriately. The composite reliability value of DAS was 0.86. The data were collected from self-administrated questionnaires. Hence, common method bias could be a problem. As suggested by Podsakoff et al,35 two post hoc statistical tests, namely Harman’s one factor test and a single-factor CFA, were conducted to examine the common method variance. Results from both tests indicated that common method bias was unlikely to be a concern in the study. For example, the result of Harman’s test revealed that seven factors with eigenvalues > 1 combined to account for 71.3% of the total variance while the first factor accounted for 31.7% of the total variance in the first group (similar results were obtained from the second group and the whole sample).
Discussion The long questionnaire developed by Oosterink et al16 prevents it from regularly being used for assessment of anxiety provoking stimuli especially in clinical dental practices where time with a patient is a premium. In addition, some items were almost identical in content to other items, causing a high degree of redundancy. The current study established a more concise measurement scale, that is DAPS, which recategorizes dental anxiety provoking stimuli into seven distinct but related factors, and is more suited to clinical based studies. The Cronbach a and AVE values obtained in this study suggest that the scale has adequate internal consistency and convergent validity. The minimum AVE value, which is greater than the square of the correlation value for each pair of factors, indicates good discriminant validity of the scale. Three factors, namely surgery, environment, and dental check-up, were found to have significant effects on DAS. The factor “surgery” may well cover Questions 3 and 4 of DAS which state that “when you are in the dentist’ chair waiting while the dentist gets the drill ready to begin working on your teeth, how do you feel?” and “you are in the dentist’s or hygienist’s chair to have your teeth cleaned; while you are waiting and the dentist is getting out
Please cite this article in press as: Wong HM, et al., Development of a dental anxiety provoking scale: A pilot study in Hong Kong, Journal of Dental Sciences (2015), http://dx.doi.org/10.1016/j.jds.2014.09.003
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Development of a dental anxiety provoking scale
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Factor structure of dental anxiety provoking sale (DAPS).
the instruments which she/he will use to scrape your teeth around the gums, how do you feel?”. The factor “environment” has items similar to Questions1 and 2 of DAS which state that “if you had to go to the dentist tomorrow, how would you feel about it?” and “when you are waiting in the
dentist’s office for your turn in the chair, how do you feel?”. While the factor “dental check-up” also covers part of Questions 1 and 2 of DAS. The findings are similar to a previous study,36 which reported that the DAS items were related to two factors: anticipation (Questions 1 and 2) and
Please cite this article in press as: Wong HM, et al., Development of a dental anxiety provoking scale: A pilot study in Hong Kong, Journal of Dental Sciences (2015), http://dx.doi.org/10.1016/j.jds.2014.09.003
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H.M. Wong et al Table 2 Descriptive statistics, reliability estimates, and inter-correlations among dental anxiety provoking sale factors and dental anxiety scale (DAS) (N Z 300; 156 females and 144 males). Factor
No. of items
Mean (SD)
a
CR
AVE
1
(1) Injection Female subgroup Male subgroup (2) Surgery Female subgroup Male subgroup (3) Perceived lack of control Female subgroup Male subgroup (4) Empathy Female subgroup Male subgroup (5). Scale and drill Female subgroup Male subgroup (6) Environment Female subgroup Male subgroup (7) Dental check-up Female subgroup Male subgroup DAS* Female subgroup Male subgroup
4
2.85 2.87 2.84 2.71 2.76 2.66 2.47
(0.79) (0.75) (0.84) (0.88) (0.86) (0.91) (0.81)
0.87
0.88
0.65
1.00
0.84
0.84
0.64
0.66
1.00
0.89
0.89
0.68
0.40
0.45
1.00
2.48 2.46 2.37 2.39 2.34 2.01 2.06 1.97 1.71 1.75 1.67 1.65 1.67 1.63 9.07 9.10 9.04
(0.79) (0.83) (0.73) (0.71) (0.76) (0.86) (0.86) (0.67) (0.70) (0.69) (0.72) (0.61) (0.61) (0.61) (3.28) (3.14) (3.43)
0.76
0.78
0.55
0.33
0.35
0.60
1.00
0.92
0.93
0.81
0.48
0.55
0.39
0.45
1.00
0.86
0.86
0.68
0.35
0.32
0.27
0.38
0.56
1.00
0.90
0.90
0.56
0.35
0.43
0.42
0.48
0.70
0.63
1.00
0.86
0.86
0.61
0.45
0.63
0.39
0.43
0.59
0.58
0.58
3
4
3
3
3
7
4
2
3
4
5
6
7
AVE Z average variance extracted; CR Z composite reliability; SD Z standard deviation. * DAS was formed as a latent variable for confirmatory factor analysis and structural equation modeling analyses.
treatment (Questions 3 and 4). Hence, the new scale DAPS covers a broader spectrum of patients’ individual dentistry related anxiety than DAS and the identified seven factors are interrelated. It is recognized that multiple measures of dental anxiety have a part to play in studying what a multifactorial psychological condition is. DAPS may also function as a further assessment to supplement initial screening, such as DAS, so that patients with higher dental fear can first be identified and the causes of their dental fear can then be addressed. A limitation of the study is the sampling of participants. Ideally, a broad sample of various age groups and socioeconomic status would assist in providing representative responses of dental anxiety-provoking situations and thoughts. Previous research has shown that people with different personal life experiences, particularly at different age groups and from different cultures, differ in terms of their behavioral and attitudinal characteristics, thus affecting anxiety towards dental treatment as well as their perception of how much various dental stimuli provoke anxiety.37e40 In the present study, the cohort effect was not measured because respondents were in the same age group and were exposed to similar social, intellectual, and cultural environments. Moreover, easily accessible dental services and frequent dental attendances (especially for the dental students, most of whom were regular dental attendees) helped university students avoid rating anxiety-provoking capacities of stimuli or situations that
they may not have encountered before; otherwise, it is conceivable that over- or less-estimation of the unfamiliar anxiety provoking stimuli in the 73-item self-administered questionnaire may be obtained from participants. This may have negatively influenced the reliability and validity of responses obtained. Their high educational background also enhanced the comprehension of the questionnaire. Thus, responses, as far as clinical applications are concerned, assist in developing an understanding of possible origins of dental anxiety and fear. The current study shows that perception of injection and surgical treatment provoked the highest anxiety in a dental setting. This result is similar to previous research findings.16,22 Although dental fear is often related to traumatic dental experiences, perceived dentist behavior had an impact on the expression and development of dental fear. Factors of empathy and lack of control revealed in this study also indicate that clinicians should be aware of the patients’ fear of dentist behavior and other anxious preoccupations.19 In particular, perceived lack of control that is a component of cognitive vulnerability8 has been found to correlate with other factors in the present study. Moreover, it has been suggested that the dentistepatient relationship is strongly related to patients’ feelings of safety and control during dental treatment.25 In summary, DAPS has appropriate psychometric properties that were demonstrated by evidences of validity and reliability. DAPS provides a more detailed profile of the patient’s specific responses to anxiety-provoking situations
Please cite this article in press as: Wong HM, et al., Development of a dental anxiety provoking scale: A pilot study in Hong Kong, Journal of Dental Sciences (2015), http://dx.doi.org/10.1016/j.jds.2014.09.003
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Development of a dental anxiety provoking scale and it is sufficiently brief to be used in clinical settings. The validity and reliability including test-retest reliability of DAPS should be examined with more representative samples to produce stable estimates, in which further adaptation of the scale may need to address cutoff point, age, gender, and race issues. Taking this into consideration, DAPS requires translating into the native language (Cantonese) before it can be applied locally in Hong Kong. Moreover, personal life experiences and environmental factors, some dispositional factors such as catastrophizing or trait anxiety, would also influence dental anxiety.37e40 The interaction between DAPS and these factors shall be investigated so that a more comprehensive and generalizable DAPS can be established.
Conflicts of interest The authors have no conflicts of interest relevant to this article.
Acknowledgments The authors acknowledge the financial support provided by the University Research Committee, the University of Hong Kong, with the Small Project Funding Grant Number: 104002439. The authors would like to thank the editor and the anonymous reviewers for their constructive suggestions and valuable comments.
Appendix 1. The identified seven factors and their items of the dental anxiety provoking sale. (1) Injection Inject 1 e Sensation of the needle Inject 2 e Sensation of pain Inject 3 e Sensation of an injection Inject 4 e Receiving an injection (2) Surgery Surgery 1 e Having some gum burned away Surgery 2 e Having root canal treatment Surgery 3 e Having dental surgery (3) Perceived lack of control Lack 1 e Perceived lack of control Lack 2 e Feeling helpless Lack 3 e The perceived fear reaction Lack 4 e The fact that you don’t know (4) Empathy Emp 1 e Lack of explanation of the dentist Emp 2 e Lack of sufficient conversation Emp 3 e A dentist in a hurry (5) Scale and Drill S&D 1 e The smell when scaling teeth S&D 2 e The smell when drilling teeth S&D 3 e The taste when scaling teeth (6) Environment Environ 1 e Approaching the dental office Environ 2 e Getting in the dental chair Environ 3 e Lying in the dental chair (position) (7) Dental check-up
7 Check Check Check Check Check Check Check
1 2 3 4 5 6 7
e e e e e e e
Having a dental check-up Keeping mouth opened The sight of the cold air spray instrument The sight of the white gown Having dental X-rays taken Having teeth cleaned Cold air spray on tooth or molar
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8 19. De Jongh A, Stouthard ME. Anxiety about dental hygienist treatment. Community Dent Oral Epidemiol 2003;21:91e5. 20. Kent G. Anxiety, pain and type of dental procedure. Behav Res Ther 1984;22:465e9. 21. Stabholz A, Peretz B. Dental anxiety among patients prior to different dental treatments. Int Dent J 1999;49:90e4. 22. Humphris GM, Freeman R, Campbell J, Tuutti H, D’Souza D. Further evidence for the reliability and validity of the Modified Dental Anxiety Scale. Int Dent J 2000;50:367e70. 23. Wong HM, Humphris GM, Lee GT. Preliminary validation and reliability of the Modified Child Dental Anxiety Scale. Psychol Rep 1998;83:1179e86. 24. Domoto PK, Weinstein P, Melnick S, et al. Results of a dental fear survey in Japan: Implications for dental public health in Asia. Community Dent Oral Epidemiol 1998;16:199e201. 25. Abrahamsson KH, Berggren U, Hallberg L, Carlsson SG. Dental phobic patients’ view of dental anxiety and experiences in dental care: a qualitative study. Scand J Caring Sci 2002;16: 188e96. 26. Cohen SM, Fiske J, Newton JT. Behavioural dentistry: the impact of dental anxiety on daily living. Br Dent J 2000;189: 385e90. 27. Churchill Jr GA. A paradigm for developing better measures of marketing constructs. J Mark Res 1979;16:64e73. 28. Bearden WO, Netemeyer RG, Haws KL. Handbook of Marketing Scales: Multi-item Measures for Marketing and Consumer Behavior Research, 3rd ed. Thousand Oaks: Sage Publications, 2011. 29. Armfield JM. A preliminary investigation of the relationship of dental fear to other specific fears, general fearfulness, disgust sensitivity and harm sensitivity. Community Dent Oral Epidemiol 2008;36:128e36. 30. Corah NL, Gale EN, Illig SJ. Assessment of a dental anxiety scale. J Am Dent Assoc 1978;97:816e9.
H.M. Wong et al 31. Nunnally JC, Bernstein IH. Psychometric Theory, 3rd ed. New York: McGraw-Hill, 1994. 32. Anderson JC, Gerbing DW. The effect of sampling error on convergence, improper solutions, and goodness-of-fit indices for maximum likelihood confirmatory factor analysis. Psychometrika 1984;49:155e73. 33. Hu LT, Bentler PM. Cutoff criteria for fit indexes in covariance structure analysis: Conventional versus new alternatives. Struct Equ Modeling 1999;6:1e55. 34. Hair JF, Black WC, Babin BJ, Anderson RE, Tatham RL. Multivariate Data Analysis, 6th ed. Upper Saddle River: Prentice Hall, 2006. 35. Podsakoff PM, MacKenzie SB, Lee JY, Podsakoff NP. Common method biases in behavioral research: a critical review of the literature and recommended remedies. J Appl Psychol 2003; 88:879e903. 36. Yuan S, Freeman R, Lahti S, Lloyd-Williams F, Humphris G. Some psychometric properties of the Chinese version of the Modified Dental Anxiety Scale with cross validation. Health Qual Life Outcomes 2008;6:22. 37. Locker D, Liddell A, Burman D. Dental fear and anxiety in an older adult population. Community Dent Oral Epidemiol 1991; 19:120e4. 38. Freeman R. The psychology of dental patient care: barriers to accessing dental care: patient factor. Br Dent J 1999;187: 141e4. 39. Eli I, Baht R, Blacher S. Prediction of success and failure of behavior modification as treatment for dental anxiety. Eur J Oral Sci 2004;112:311e5. 40. Suprabha BS, Rao A, Choudhary S, Shenoy R. Child dental fear and behavior: the role of environmental factors in a hospital cohort. J Indian Soc Pedod Prev Dent 2011;29: 95e101.
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Journal of Dental Sciences (2015) xx, 1e8
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ORIGINAL ARTICLE
Development of a dental anxiety provoking scale: A pilot study in Hong Kong Hai Ming Wong a*, Cheuk Ming Mak b, Wai Ming To c a
Department of Paediatric Dentistry and Orthodontics, Faculty of Dentistry, the University of Hong Kong, Hong Kong b Department of Building Services Engineering, the Hong Kong Polytechnic University, Hong Kong c School of Business, Macao Polytechnic Institute, Macao, China Received 22 May 2014; Final revision received 29 August 2014
Available online - - -
KEYWORDS dental anxieties; pilot study; test anxiety scale
Abstract Background/purpose: Dental anxiety is closely related to one’s past experience in dental clinics. However, little is known about what clinical, environmental, and psychological aspects provoke anxiety in dental patients. Extending on previous work in The Netherlands which explored anxiety provoking stimuli, the objective of the study was to develop a Dental Anxiety Provoking Scale (DAPS) that measures the degree to which anxiety was provoked by dental stimuli and to identify the underlying factor structure of the DAPS. Materials and methods: Four hundred and sixty study participants were recruited from two universities in Hong Kong. Each participant completed a self-administrated questionnaire that included a 73-item measure of dental anxiety provoking stimuli, and a four-item dental anxiety scale. Results: Results of exploratory and confirmatory factor analyses showed that the DAPS has seven factors, namely, dental check-up, injection, scale and drill, surgery, empathy, perceived lack of control, and clinic environment, and has 27 items. Results of structural equation modeling showed that three factors of the DAPS; dental check-up, surgery, and clinic environment, had a significant effect on dental anxiety score. The Cronbach a values ranged from 0.76 to 0.92 while the composite reliability values ranged from 0.78 to 0.93. The average variance extracted (AVE) values ranged from 0.55 to 0.81. The minimum AVE value was greater than the square of correlation value for each pair of factors. Conclusion: The study developed and validated the DAPS covering a wide range of dental anxiety provoking stimuli, findings were concise enough to be used in clinical based studies. Copyright ª 2015, Association for Dental Sciences of the Republic of China. Published by Elsevier Taiwan LLC. All rights reserved.
* Corresponding author. Department of Paediatric Dentistry and Orthodontics, Faculty of Dentistry, the University of Hong Kong, 2/F Prince Philip Dental Hospital, 34 Hospital Road, Hong Kong. E-mail address: [email protected] (H.M. Wong). http://dx.doi.org/10.1016/j.jds.2014.09.003 1991-7902/Copyright ª 2015, Association for Dental Sciences of the Republic of China. Published by Elsevier Taiwan LLC. All rights reserved.
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H.M. Wong et al
Introduction
Materials and methods
Dental anxiety has been a research focus over the past several decades.1e9 Despite the advances in dental equipment and procedures, dental anxiety is still recognized as a major issue in the provision of dental care.2,3,5e10 Patients with high dental anxiety recall more pain than they actually experienced in tooth extraction.11 Empirical evidence demonstrated that a high level of dental anxiety was significantly associated with irregular dental attendance,12,13 delays in dental treatment,10 and dental avoidance.14,15 Armfield et al10 reported that high dental anxiety was related to less frequent dental visits, more severe dental problems, and only visiting dental clinics for painful dental problems. Hence, high dental anxiety is significantly associated with poor oral health.5,10 In addition, it was found that parents’ dental anxiety and avoidance behaviors were related to dental caries in children.15 Hence the vicious cycle of dental anxiety not only affects a person’s oral health but may also affect the person’s next of kin. The existing literature has put a lot of emphasis on the consequences of dental anxiety. However, the current study examines what causes dental anxiety. Although dental anxiety is shown to be closely related to one’s past experience in dental clinics,16e18 the provoking effect of clinical and environmental aspects on the anxiety of dental patients has yet to be comprehensively studied. Oosterink et al16 conducted an extensive literature review and found that most literature focused on certain aspects of anxiety provoking stimuli and practices in the dental setting. The most common aspects include pain sensations,19,20 having dental surgery,21 having an injection,22,23 sight, sound, and feeling of the drill,12,19,24 negative dentist behavior,25 various aspects of clinical environment such as the sight and sound of dental chair and equipment,12 the smell of the clinic,18,24,26 and perceived lack of control.18,26 Oosterink et al16 compiled a questionnaire that covered 67 potentially anxiety provoking stimuli in the dental setting and tested the questionnaire using a convenience sample in The Netherlands. They aimed to establish a hierarchy of anxiety provoking stimuli. Using the Scree plot of eigenvalues from the exploratory factor analysis they found that stimuli could be categorized by two sets of factors: (1) invasivetreatment-related stimuli factors; and (2) noninvasivetreatment-related stimuli factors. Oosterink et al16 showed that the number of extreme anxiety-provoking stimuli had the greatest influence on the dental anxiety score (DAS) using stepwise regression analysis. However, Oosterink et al16 did not continue to investigate the factor structure of those stimuli in detail and did not establish the relationships between anxiety provoking stimuli factors and DAS. The current study addresses these gaps in dental research by establishing a Dental Anxiety Provoking Scale (DAPS) and examining the relationship between DAPS and dental anxiety. The developed DAPS is more concise and better suited for clinical use. This study followed established procedures for scale development in social science starting with identification of an item pool, checking the face and content validity of the items, collecting data, performing exploratory and confirmatory factor analyses, and ending with assessing external validity of the scale.
Participants A convenience sample of university students in Hong Kong was recruited from the University of Hong Kong (250 students) and the Hong Kong Polytechnic University (400 students). Out of the sample of 650 students, 460 students (230 students from each university) completed and returned questionnaires, representing a response rate of 71%. All of the participants had dental experience as free dental check-ups and treatment are provided in the universities, and 95% of school children join the School Dental Care Service provided by the Department of Health, Government of Hong Kong Special Administrative Region. University students were selected because they have the language ability to respond to an English questionnaire and they can articulate their experiences in the dental setting. The problems inherent in translation were avoided. Out of the 460 respondents, 230 (50%) were female. The largest group of respondents were aged 20e21 years (n Z 160), followed by 22e23 years (n Z 140), 18e19 years (n Z 120), < 18 years (n Z 20), and 24 years (n Z 20). It should be noted that the use of students as study participants may threaten the generalizability of the study findings due to the unique characteristics of the student population.
Data collection Ethical approval was obtained from the Institutional Review Board of the University of Hong Kong/Hospital Authority Hong Kong West Cluster (UW 14e010). Teaching assistants invited students who attended lectures and tutorials in various faculties to participate. Participation was voluntary and selfadministered anonymous questionnaires were used to collect data. Informed consent was obtained from all participants. Teaching assistants distributed the questionnaires in the classroom and participants were asked to return the questionnaires in 15 minutes, before lectures/tutorials began.
Instrument: Dental anxiety provoking stimuli This list contains 73 items covering a wide range of situations and stimuli that provoke a person’s anxiety toward dentistry. The stimuli include the 67 potential anxiety provoking stimuli adopted from Oosterink et al16 and the following six items proposed by the authors: (1) sight of the scaler; (2) the smell when scaling teeth; (3) the taste when scaling teeth; (4) the sound of scaling teeth; (5) sensation of the active scaler; and (6) the taste when drilling teeth. The items were reviewed by two faculty members and 10 students in the Faculty of Dentistry to ensure face and content validity.27,28 All items were rated on a 4-point Likert scale ranging from 1, representing not anxiety provoking at all, to 4, representing extremely anxiety provoking.
Instrument: Dental anxiety scale (DAS) DAS is a four-item measure designed to assess a person’s anxiety toward dentistry. The scale was developed by
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Development of a dental anxiety provoking scale
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Corah1 and has been the most widely used measure in dental anxiety studies.29 The participant is asked to imagine her/himself in four different dental situations and to rate how she/he feels, from “reasonably enjoyable/ relaxed” to “very frightened/almost feel physically sick”. High scores indicate high dental anxiety. The Cronbach a values of the DAS were 0.89 and 0.86 in a study by Eli et al.4
analysis (CFA) was performed on the second group of samples using structural equation modeling to further investigate the stability and validity of the scale identified in EFA.
Results Exploratory factor analysis
Statistical analysis
Based on the initial 73-item measure, Bartlett’s test of sphericity was found to be significant (c2 Z 10,685; df Z 2,628; P < 0.001) and the Kaiser-Meyer-Olkin measure of sampling adequacy was 0.94. These results suggested that the correlation matrix was not an identity matrix and the inter-correlation matrix contained enough common variance to make factor analysis worthwhile. The EFA was then performed using principal components analysis with varimax rotation. By deleting items with loadings < 0.6 and cross-loading > 0.4 iteratively, a seven-factor structure of DAPS that explained 71.3% of the variance of the measures was identified. The identified seven factors are injection (4 items), surgery (3 items), scale and drill (3 items), perceived lack of control (4 items), empathy (3 items), environment (3 items), and dental check-up (7 items). Table 1 shows descriptive statistics, reliability estimates (Cronbach a values), and bivariate correlations among the identified variables using the first group of samples (n Z 160; 74 females and 86 males). In general terms, this
The collected data were coded and analyzed using SPSS version 17.0 and AMOS 17.0 (SPSS Inc., Chicago, IL, USA). Following established procedures for scale development28 the data were randomly split into two groups: 160 for the first group and the remaining 300 for the second group. Chisquare tests and independent t tests were performed. Results showed that there was no statistically significant difference in demographic data and item scores between the two groups and the whole sample. Exploratory factor analysis (EFA) was performed on the first group of samples to identify factor structures using principal component analysis with varimax rotation. The latent root criterion and a scree plot were used simultaneously to determine the number of factors. Items with loadings < 0.6 and crossloading > 0.4 on more than one factor were deleted iteratively. The results from the EFA would yield theoretically meaningful, interpretable factors. Confirmatory factor
Table 1 Descriptive statistics, reliability estimates, and bivariate correlations between the variables identified in exploratory factor analysis and dental anxiety scale (DAS) scores (N Z 160; 74 females and 86 males). Factor
No. of items
Mean (SD)
a
1
(1) Injection Female subgroup Male subgroup (2)Surgery Female subgroup Male subgroup (3)Perceived lack of control Female subgroup Male subgroup (4)Empathy Female subgroup Male subgroup (5)Scale and drill Female subgroup Male subgroup (6)Environment Female subgroup Male subgroup (7)Dental check-up Female subgroup Male subgroup DAS (Total score) Female subgroup Male subgroup
4
2.68 2.71 2.64 2.61 2.66 2.57 2.33
(0.88) (0.82) (0.93) (0.92) (0.90) (0.95) (0.82)
0.89
1.00
0.84
0.51
1.00
0.89
0.42
0.48
1.00
2.29 2.36 2.32 2.28 2.35 1.95 2.02 1.88 1.71 1.74 1.68 1.59 1.52 1.65 8.57 8.97 8.38
(0.82) (0.83) (0.77) (0.75) (0.78) (0.81) (0.87) (0.77) (0.77) (0.85) (0.70) (0.64) (0.62) (0.65) (3.30) (3.10) (3.46)
0.83
0.36
0.43
0.51
1.00
0.87
0.52
0.47
0.35
0.37
1.00
0.90
0.38
0.38
0.26
0.28
0.61
1.00
0.91
0.32
0.34
0.27
0.36
0.58
0.63
1.00
0.85
0.39
0.48
0.35
0.28
0.59
0.61
0.49
3
4
3
3
3
7
4
2
3
4
5
6
7
SD Z standard deviation.
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4 group of respondents indicated that perceptions of injection [mean (M) Z 2.68, standard deviation (SD) Z 0.88] and surgery (M Z 2.61, SD Z 0.92) are anxiety-provoking events and showed moderate levels of dental anxiety (M Z 8.66, SD Z 3.30). Among the 160 respondents, 20 (12.5%) were classified as dentally anxious individuals because they had a DAS score of 13 or more.30 The Cronbach a values ranged from 0.83 to 0.91, all greater than the threshold of 0.7 for internal consistency.31 Female respondents showed a relatively higher anxiety toward injection, surgery, scale and drill, and environment while male respondents showed a relatively higher anxiety toward perceived lack of control, empathy, and dental check-up as shown in Table 1. However, independent t tests showed that the differences between females and males on the seven identified factors and the DAS were too small to be significant. The seven factors and the associated 27 items identified are given in Appendix 1.
Confirmatory factor analysis CFA was applied to the data from the second group of samples i.e. 300 respondents. The CFA results confirmed the seven-factor structure identified in the EFA as an acceptable structure. Fig. 1 shows the factor structure of the CFA model. The fit indices of this measurement model were: c2/df Z 2.16 (c2 Z 655.6; df Z 303), goodness of fit index (GFI) Z 0.86, comparative fit index (CFI) Z 0.93, root mean square residual (RMSR) Z 0.04, and root mean square error of approximation (RMSEA) Z 0.06 in which GFI and CFI were >0.85 (i.e., acceptable) and 0.90 (i.e., good), RMSR and RMSEA were <0.08, respectively.32,33 The average variance extracted (AVE) was computed using standardized loadings. The measurement errors and AVE were used to assess the convergent validity and the discriminant validity of the factors. Table 2 shows descriptive statistics, reliability estimates including Cronbach a values, composite reliability (CR) and AVE values, inter-correlations of the seven factors, and DAS. This group of respondents indicated that perceptions of injection (M Z 2.85, SD Z 0.79) and surgery (M Z 2.71, SD Z 0.88) are anxiety-provoking events and showed moderate levels of dental anxiety (M Z 9.07, SD Z 3.28). Independent t tests showed that there were no significant differences between the second group of respondents and the first group of respondents. Among the 300 respondents, 45 (15%) were classified as dentally anxious individuals because they had a DAS score of 13. In this group of respondents, females showed a relatively higher anxiety toward the identified seven factors and had a relatively higher DAS score (Table 2). However, independent t tests showed that the differences between females and males on all factors and DAS were too small to be significant. The Cronbach a values ranged from 0.76 to 0.92 while the CR values ranged from 0.78 to 0.93, suggesting that the factors have high internal reliability. The AVE values ranged from 0.55 to 0.81. These values were greater than the threshold of 0.5, suggesting that each factor has adequate convergent validity and measures its intended concept.34 Discriminant validity, i.e., the degree to which factors are distinct, was assessed by comparing the minimum AVE value
H.M. Wong et al for each pair of factors with the square of the correlation between two factors. The minimum AVE value was greater than the square of the correlation value for each pair of factors, indicating good discriminant validity. The predictive validity of DAPS was assessed by using structural equation modeling (SEM). In this case, DAS was employed as the outcome variable while the seven factors were treated as independent variables. The structural model showed that three factors including surgery, environment, and dental check-up had significant effects on DAS. The path estimates between surgery and DAS, environment and DAS, and dental check-up were 0.44, 0.30, and 0.21, respectively. The results indicated that a person’s perception of surgical treatment strongly and significantly provoked anxiety, followed by perception of getting into the dental office and lying in the dental chair (i.e., clinic environment), and a general perception of having a dental check-up. The fit indices of this structural model were: c2/ df Z 2.10 (c2 Z 860.5; df Z 410), GFI Z 0.85, CFI Z 0.93, RMSR Z 0.05, and RMSEA Z 0.06, suggesting that the structural model fitted the data appropriately. The composite reliability value of DAS was 0.86. The data were collected from self-administrated questionnaires. Hence, common method bias could be a problem. As suggested by Podsakoff et al,35 two post hoc statistical tests, namely Harman’s one factor test and a single-factor CFA, were conducted to examine the common method variance. Results from both tests indicated that common method bias was unlikely to be a concern in the study. For example, the result of Harman’s test revealed that seven factors with eigenvalues > 1 combined to account for 71.3% of the total variance while the first factor accounted for 31.7% of the total variance in the first group (similar results were obtained from the second group and the whole sample).
Discussion The long questionnaire developed by Oosterink et al16 prevents it from regularly being used for assessment of anxiety provoking stimuli especially in clinical dental practices where time with a patient is a premium. In addition, some items were almost identical in content to other items, causing a high degree of redundancy. The current study established a more concise measurement scale, that is DAPS, which recategorizes dental anxiety provoking stimuli into seven distinct but related factors, and is more suited to clinical based studies. The Cronbach a and AVE values obtained in this study suggest that the scale has adequate internal consistency and convergent validity. The minimum AVE value, which is greater than the square of the correlation value for each pair of factors, indicates good discriminant validity of the scale. Three factors, namely surgery, environment, and dental check-up, were found to have significant effects on DAS. The factor “surgery” may well cover Questions 3 and 4 of DAS which state that “when you are in the dentist’ chair waiting while the dentist gets the drill ready to begin working on your teeth, how do you feel?” and “you are in the dentist’s or hygienist’s chair to have your teeth cleaned; while you are waiting and the dentist is getting out
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Development of a dental anxiety provoking scale
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Factor structure of dental anxiety provoking sale (DAPS).
the instruments which she/he will use to scrape your teeth around the gums, how do you feel?”. The factor “environment” has items similar to Questions1 and 2 of DAS which state that “if you had to go to the dentist tomorrow, how would you feel about it?” and “when you are waiting in the
dentist’s office for your turn in the chair, how do you feel?”. While the factor “dental check-up” also covers part of Questions 1 and 2 of DAS. The findings are similar to a previous study,36 which reported that the DAS items were related to two factors: anticipation (Questions 1 and 2) and
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H.M. Wong et al Table 2 Descriptive statistics, reliability estimates, and inter-correlations among dental anxiety provoking sale factors and dental anxiety scale (DAS) (N Z 300; 156 females and 144 males). Factor
No. of items
Mean (SD)
a
CR
AVE
1
(1) Injection Female subgroup Male subgroup (2) Surgery Female subgroup Male subgroup (3) Perceived lack of control Female subgroup Male subgroup (4) Empathy Female subgroup Male subgroup (5). Scale and drill Female subgroup Male subgroup (6) Environment Female subgroup Male subgroup (7) Dental check-up Female subgroup Male subgroup DAS* Female subgroup Male subgroup
4
2.85 2.87 2.84 2.71 2.76 2.66 2.47
(0.79) (0.75) (0.84) (0.88) (0.86) (0.91) (0.81)
0.87
0.88
0.65
1.00
0.84
0.84
0.64
0.66
1.00
0.89
0.89
0.68
0.40
0.45
1.00
2.48 2.46 2.37 2.39 2.34 2.01 2.06 1.97 1.71 1.75 1.67 1.65 1.67 1.63 9.07 9.10 9.04
(0.79) (0.83) (0.73) (0.71) (0.76) (0.86) (0.86) (0.67) (0.70) (0.69) (0.72) (0.61) (0.61) (0.61) (3.28) (3.14) (3.43)
0.76
0.78
0.55
0.33
0.35
0.60
1.00
0.92
0.93
0.81
0.48
0.55
0.39
0.45
1.00
0.86
0.86
0.68
0.35
0.32
0.27
0.38
0.56
1.00
0.90
0.90
0.56
0.35
0.43
0.42
0.48
0.70
0.63
1.00
0.86
0.86
0.61
0.45
0.63
0.39
0.43
0.59
0.58
0.58
3
4
3
3
3
7
4
2
3
4
5
6
7
AVE Z average variance extracted; CR Z composite reliability; SD Z standard deviation. * DAS was formed as a latent variable for confirmatory factor analysis and structural equation modeling analyses.
treatment (Questions 3 and 4). Hence, the new scale DAPS covers a broader spectrum of patients’ individual dentistry related anxiety than DAS and the identified seven factors are interrelated. It is recognized that multiple measures of dental anxiety have a part to play in studying what a multifactorial psychological condition is. DAPS may also function as a further assessment to supplement initial screening, such as DAS, so that patients with higher dental fear can first be identified and the causes of their dental fear can then be addressed. A limitation of the study is the sampling of participants. Ideally, a broad sample of various age groups and socioeconomic status would assist in providing representative responses of dental anxiety-provoking situations and thoughts. Previous research has shown that people with different personal life experiences, particularly at different age groups and from different cultures, differ in terms of their behavioral and attitudinal characteristics, thus affecting anxiety towards dental treatment as well as their perception of how much various dental stimuli provoke anxiety.37e40 In the present study, the cohort effect was not measured because respondents were in the same age group and were exposed to similar social, intellectual, and cultural environments. Moreover, easily accessible dental services and frequent dental attendances (especially for the dental students, most of whom were regular dental attendees) helped university students avoid rating anxiety-provoking capacities of stimuli or situations that
they may not have encountered before; otherwise, it is conceivable that over- or less-estimation of the unfamiliar anxiety provoking stimuli in the 73-item self-administered questionnaire may be obtained from participants. This may have negatively influenced the reliability and validity of responses obtained. Their high educational background also enhanced the comprehension of the questionnaire. Thus, responses, as far as clinical applications are concerned, assist in developing an understanding of possible origins of dental anxiety and fear. The current study shows that perception of injection and surgical treatment provoked the highest anxiety in a dental setting. This result is similar to previous research findings.16,22 Although dental fear is often related to traumatic dental experiences, perceived dentist behavior had an impact on the expression and development of dental fear. Factors of empathy and lack of control revealed in this study also indicate that clinicians should be aware of the patients’ fear of dentist behavior and other anxious preoccupations.19 In particular, perceived lack of control that is a component of cognitive vulnerability8 has been found to correlate with other factors in the present study. Moreover, it has been suggested that the dentistepatient relationship is strongly related to patients’ feelings of safety and control during dental treatment.25 In summary, DAPS has appropriate psychometric properties that were demonstrated by evidences of validity and reliability. DAPS provides a more detailed profile of the patient’s specific responses to anxiety-provoking situations
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Development of a dental anxiety provoking scale and it is sufficiently brief to be used in clinical settings. The validity and reliability including test-retest reliability of DAPS should be examined with more representative samples to produce stable estimates, in which further adaptation of the scale may need to address cutoff point, age, gender, and race issues. Taking this into consideration, DAPS requires translating into the native language (Cantonese) before it can be applied locally in Hong Kong. Moreover, personal life experiences and environmental factors, some dispositional factors such as catastrophizing or trait anxiety, would also influence dental anxiety.37e40 The interaction between DAPS and these factors shall be investigated so that a more comprehensive and generalizable DAPS can be established.
Conflicts of interest The authors have no conflicts of interest relevant to this article.
Acknowledgments The authors acknowledge the financial support provided by the University Research Committee, the University of Hong Kong, with the Small Project Funding Grant Number: 104002439. The authors would like to thank the editor and the anonymous reviewers for their constructive suggestions and valuable comments.
Appendix 1. The identified seven factors and their items of the dental anxiety provoking sale. (1) Injection Inject 1 e Sensation of the needle Inject 2 e Sensation of pain Inject 3 e Sensation of an injection Inject 4 e Receiving an injection (2) Surgery Surgery 1 e Having some gum burned away Surgery 2 e Having root canal treatment Surgery 3 e Having dental surgery (3) Perceived lack of control Lack 1 e Perceived lack of control Lack 2 e Feeling helpless Lack 3 e The perceived fear reaction Lack 4 e The fact that you don’t know (4) Empathy Emp 1 e Lack of explanation of the dentist Emp 2 e Lack of sufficient conversation Emp 3 e A dentist in a hurry (5) Scale and Drill S&D 1 e The smell when scaling teeth S&D 2 e The smell when drilling teeth S&D 3 e The taste when scaling teeth (6) Environment Environ 1 e Approaching the dental office Environ 2 e Getting in the dental chair Environ 3 e Lying in the dental chair (position) (7) Dental check-up
7 Check Check Check Check Check Check Check
1 2 3 4 5 6 7
e e e e e e e
Having a dental check-up Keeping mouth opened The sight of the cold air spray instrument The sight of the white gown Having dental X-rays taken Having teeth cleaned Cold air spray on tooth or molar
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Please cite this article in press as: Wong HM, et al., Development of a dental anxiety provoking scale: A pilot study in Hong Kong, Journal of Dental Sciences (2015), http://dx.doi.org/10.1016/j.jds.2014.09.003
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Please cite this article in press as: Wong HM, et al., Development of a dental anxiety provoking scale: A pilot study in Hong Kong, Journal of Dental Sciences (2015), http://dx.doi.org/10.1016/j.jds.2014.09.003