DOI: 10.1111/ipd.12106
Reliability and validity of the Chinese version of the Children’s Fear Survey Schedule-Dental Subscale LIN MA1, MENG WANG2, QUAN JING1, JIZHI ZHAO1, KUO WAN1 & QUN XU2 1
Department of Stomatology, Peking Union Medical College Hospital, Beijing, China, and 2Department of Epidemiology and Biostatistics, Institute of Basic Medicine Sciences Chinese Academy of Medical Sciences & School of Basic Medicine Peking Union Medical College, Beijing, China
International Journal of Paediatric Dentistry 2015; 25: 110–116 Background. The Children’s Fear Survey Schedule-
Dental Subscale (CFSS-DS) is a commonly used questionnaire that measures children’s dental fears. Aim. This study aimed to examine the reliability and validity of the Chinese version of the CFSSDS. Design. The CFSS-DS was translated into Chinese and administered to children in a dental office. The sample comprised 206 child patients aged 6–10 years, 42 of whom were selected for test– retest analysis. The behaviors of all 206 children were rated during their dental appointments and compared to their questionnaire results.
Introduction
Children commonly experience anxiety when receiving professional dental treatment, and feelings of anxiety during dental treatment can lead to uncooperative behavior that may obstruct and delay treatment. Childhood dental fear has been shown to be widespread, with a prevalence ranging from 6% to 20%, depending in part on how it is measured, the ages of the children being assessed, and the culture1. Several different methods have been used to assess dental fear in children, including behavioral ratings such as the Frankl Scale2, physiological measurements such as heart rate3, and questionnaires. Developed in 19824, the Dental Subscale of the Children’s Fear Survey Schedule (CFSSDS) is a well-known questionnaire for
Correspondence to: Prof K. Wan, Department of Stomatology, Peking Union Medical College Hospital, 1 Shuaifuyuan, Dongcheng District, Beijing 100730, China. E-mail: [email protected]
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Results. The internal consistency (Cronbach’s a) was 0.85, and the test–retest reliability (intraclass correlation) was 0.71. The Chinese version of the CFSS-DS showed good criterion validity; children who were uncooperative on the Frankl Scale had higher mean CFSS-DS scores (Z = 5.79). Through factorization, three factors emerged: (1) dental treatment, (2) hospital personnel, and (3) invasive dental procedures. Girls reported more fear than boys (21.79 vs 19.91), and children who had painful dental experiences reported more fear (30.87 vs 20.00). Conclusion. These results suggest that the CFSSDS is reliable and valid and operates in China as it does in other cultures. Further studies should include school samples to evaluate children who may not go to the dentist.
assessing dental fear in children. This scale consists of 15 items related to various aspects of dental treatment, such as injections, having to open one’s mouth, and drilling. The CFSS-DS has been widely used in recent studies and has been shown to be a valuable and adequate measure of dental fear in children5–7. In contrast to other self-reporting measurements, such as the Venham Picture Test and Dental Anxiety Scale, the CFSS-DS covers more aspects of the dental situation and measures dental fear more precisely8. The CFSS-DS has been translated into several languages and has been studied in several countries, and the results of these studies showed that the CFSSDS exhibits good internal and test–retest reliability in English as well as in several other languages5,6,9–17. Cultural differences, however, play an important role in building the psychology of a child, and scales that possess great reliability in some parts of the world may not have universal validity unless it is confirmed to be unaffected by cultural differences7. The present investigation was carried
© 2014 BSPD, IAPD and John Wiley & Sons A/S. Published by John Wiley & Sons Ltd
CFSS-DS in Chinese children
out to test the reliability and validity of a Chinese version of the CFSS-DS in the Chinese mainland. Materials and methods
Local children between the ages of 6 and 10 years attending primary school in Beijing who were seen at the Dental Department at Peking Union Medical College Hospital from June 2011 to August 2013 were recruited for this study. Children who had immigrated to Beijing from other cities, with cognitive disorders, and children with mental disorders were excluded from the study. This study was approved by the Ethics Committee of the Peking Union Medical College Hospital (No.: S-323). Parents provided written consent, and the children provided verbal assent. Development of the Chinese version of the CFSS-DS The children’s questionnaire consisted of the CFSS-DS items and a 5-point pictorial scale [Facial Image Scale (FIS)]18. The FIS consisted of five drawings of a face, displaying affective features ranging from extremely positive to neutral to extremely negative. The children were presented with the five images and asked to select the one that best corresponded to how they were feeling. The faces were scored on a scale from 1 to 5, with 1 assigned to the most positive face and 5 assigned to the most negative face. Pilot testing revealed that young children were able to answer the CFSS-DS items by referencing the facial images. To maintain consistency, all children saw the facial images during the questionnaire administration. The CFSS-DS was translated from English into Chinese by a single native speaker and subsequently back-translated by another native speaker to ensure comparability with the original form (the translation is available from the corresponding author). The Chinese version was then pre-tested in a small group of Chinese children, and the translation was modified to further ensure comparability. The dental items were summed to create an index of the child’s dental fear, with scores ranging from 15 to 75.
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Reliability study The internal reliability and criterion validity of the developed questionnaire was assessed in 206 children aged 6–10 years who were seen at the Dental Department at Peking Union Medical College Hospital. The questionnaire was completed in the waiting room of the dental practice prior to treatment. The CFSS-DS was read out loud to each child in the waiting room by one of the researchers, employing a script to introduce the survey consistently. The parents were not allowed to participate or help their children complete the questionnaire. Among the 206 children, 42 returned for dental treatment after 4 weeks. To measure test–retest reliability in these 42 children, the CFSS-DS was administered a second time to the children in the waiting room 4 weeks after the first test. Validity study During the first dental appointment, the child’s behavior was assessed by a trained observer in accordance with the Frankl Scale at several points during treatment, such as during the oral examination, upon injection, and other points. The observer was previously trained in the use of the Frankl Scale and calibrated in a previous research project. The child’s overall Frankl score was defined as his/her lowest Frankl score for any segment of treatment. The Frankl Scale consists of a 4-point scale in which 1 represents ‘definitely negative’ (e.g., the child is crying forcefully, behaving in a fearful manner), 2 represents ‘negative’ (the child is reluctant, uncooperative), 3 represents ‘positive’ (the child may be cautious but willing to comply), and 4 represents ‘definitely positive’ (the child is laughing and enjoying the situation). Children in Frankl categories 1 or 2 were combined into the negative group, and children in Frankl categories 3 or 4 were combined into the positive group. The CFSS-DS scores were unknown to the observer performing the behavior ratings. Criterion validity was assessed to examine the relationship between the CFSS-DS scores and cooperation during the dental examination and treatment.
© 2014 BSPD, IAPD and John Wiley & Sons A/S. Published by John Wiley & Sons Ltd
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All 206 children were asked whether they had previous dental experience. If yes, they were asked to rate their pain in their previous treatments, with 1 representing ‘no pain at all’, 2 representing ‘a little pain or not bad’, 3 representing ‘pain’, and 4 representing ‘a lot of pain’. Children who provided a rating of ‘1’ or ‘2’ were combined into the ‘no painful experience’ group. Children who provided a rating of ‘3’ or ‘4’ were combined into the ‘painful experience’ group. The type of treatment of each child received was also recorded for all questionnaires. Children who received an examination, fissure treatment, cleaning and simple restoration were categorized as ‘non-traumatic treatment’ group, whereas those who received extraction, deep caries restoration, surgery and root canal treatment were categorized as ‘traumatic treatment’ group. Statistical analyses Data were entered into the computer and checked for accuracy. Data management and analyses were conducted using SAS/STAT, release 8.2 (SAS Institute Inc., Cary, NC, USA). Cronbach’s a was used to compute the internal consistency based on all 206 children. Intraclass correlation was used to assess the test–retest reliability of the 42 paired CFSS-DS questionnaires. Because the CFSS-DS scores were not expected to be normally distributed (most children scoring low), the Wilcoxon test was used to compare the CFSS-DS scores between ‘negative’ and ‘positive’ children, between ‘non-traumatic treatment’ group and ‘traumatic treatment’ group, and between boys and girls. The Wilcoxon test was also used to determine the relationship between types of treatment at the first appointment and the CFSS-DS scores at the second appointment. Spearman’s rho was used to determine the relationship between the CFSS-DS scores and age. A factor analysis (principal components, varimax rotation) was also employed. Results
Of the 262 eligible children, 238 children (approximately 91%) and their parents
agreed to participate in the study. A total of 206 children (114 girls and 92 boys) completed the CFSS-DS and were enrolled in this study. The children were primarily seen for root canal treatment (22.8%), simple restoration (22.3%), or deep caries restoration (21.4%), followed by extraction (12.6%), examination (12.1%), fissure treatment (4.85%), and cleaning (3.88%). The mean CFSS-DS score was 21.0 6.57 (range = 15– 55). Cronbach’s a was 0.85. Of the 42 children who completed the questionnaire twice, the test–retest reliability was 0.71 (P < 0.01). No age differences in the CFSS-DS scores were found (P > 0.05), and girls showed significantly higher scores than boys (21.79 7.06 vs 19.91 5.78, Z = 2.004, P < 0.05). For all children, as well as for boys and girls separately, the means and SDs for all items are shown in Table 1. Among the 206 children tested, six child received a score of ‘1’ (definitely negative) on the Frankl Scale, 25 children received a score of ‘2’ (negative), 90 received a score of ‘3’ (positive), and 85 received a score of ‘4’ (definitely positive). Children categorized as negative on the Frankl Scale showed significantly higher levels of dental fear on the CFSS-DS than those categorized as positive (mean scores 28.39 9.61 vs 19.63 4.83, Z = 5.79, P < 0. 01). A total of 92 children were categorized in the ‘non-traumatic treatment’ group, and 114 children were categorized in the ‘traumatic treatment’ group. There were no significant differences in type of treatment between the 206 children (20.50 6.57 vs 21.32 6.58, P > 0.05). The CFSS-DS scores of the 156 children who had experienced prior dental treatment were not different from those of the 50 children who had not had previous dental treatment (21.04 7.03 vs 20.66 4.92, P > 0.05). The CFSS-DS scores of the 15 children who were in ‘painful experience group’ were significantly higher than those of the 141 children who were in ‘no painful experience group’ (30.87 11.17 vs 20.00 5.54, P < 0.01). For the 42 children, the type of treatment at the first appointment was not related to
© 2014 BSPD, IAPD and John Wiley & Sons A/S. Published by John Wiley & Sons Ltd
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Table 1. Mean Children’s Fear Survey Schedule-Dental Subscale item scores and standard deviations (SDs) for all children, boys, and girls. All children
Boys
Girls
Item
Mean
SD
Mean
SD
Mean
SD
Dentists Doctors Injections (shots) The dentist examining your mouth Having to open your mouth Being touched by a dentist Being seen by a dentist The dentist drilling The sight of the dentist drilling The noise of the dentist drilling The dentist putting instruments in your mouth Choking Having to go to the hospital People in white uniforms Having your teeth brushed by a dentist
1.35 1.25 2.18 1.19
0.63 0.60 1.32 0.56
1.29 1.22 1.99 1.15
0.52 0.61 1.22 0.49
1.40 1.27 2.34 1.23
0.70 0.60 1.39 0.61
1.26 1.23 1.19 2.17 1.29 1.44 1.29
0.72 0.69 0.61 1.90 0.67 0.90 0.65
1.25 1.20 1.11 2.02 1.18 1.29 1.29
0.66 0.47 0.40 1.20 0.53 0.73 0.72
1.27 1.26 1.25 2.28 1.37 1.55 1.28
0.76 0.82 0.73 1.17 0.76 1.00 0.59
1.59 1.29 1.05 1.18
0.90 0.72 0.27 0.51
1.54 1.17 1.02 1.17
0.88 0.52 0.15 0.53
1.62 1.38 1.08 1.19
0.92 0.82 0.33 0.50
the sum of the CFSS-DS scores at the second appointment (P > 0.05). The factor analysis pattern after varimax rotation is shown in Table 2. Three factors were identified, which together account for 53.70% of the variance. Factor I, accounting
Table 2. Rotated CFSS-DS factor matrix. Item Dentists Doctors Injections (shots) The dentist examining your mouth Having to open your mouth Being touched by a dentist Being seen by a dentist The dentist drilling The sight of the dentist drilling The noise of the dentist drilling The dentist putting instruments in your mouth Choking Having to go to the hospital People in white uniforms Having your teeth brushed by a dentist
Factor I
Factor II
Factor III
0.317 0.051 0.001 0.427
0.526 0.582 0.078 0.621
0.446 0.330 0.814 0.008
0.738 0.791 0.693 0.185 0.164
0.107 0.106 0.152 0.342 0.555
0.221 0.125 0.038 0.701 0.040
0.455
0.197
0.558
0.352
0.437
0.210
0.555 0.524
0.043 0.443
0.529 0.225
0.003 0.157
0.652 0.740
0.120 0.108
Strong factor loadings are presented in bold font.
for 35.77% of the variance, was characterized by the fear of dental treatment, including having to open your mouth, and choking. Factor II, which was characterized by the fear of hospital personnel, such as doctor, dentist, and people in while uniform, accounted for 9.80% of the variance. Factor III, which was characterized by the fear of invasive dental procedures, including drilling and injection, accounted for 8.12% of the variance. Discussion
Dental fear research in children has been carried out in a number of countries. As cultural and social norms of behavior can affect the development and expression of children’s fear, and as dental care systems can vary considerably across cultures, normative data in each culture are needed. In this study, the Chinese version of the CFSS-DS demonstrated an acceptable level of internal consistency, with a Cronbach’s a of 0.85. The internal consistency of the CFSS-DS has been reported to range from 0.85 to 0.925–7. These results further support the homogeneity of the scale, that is, that all items on the scale tap the same construct19. Therefore, this Chinese version of
© 2014 BSPD, IAPD and John Wiley & Sons A/S. Published by John Wiley & Sons Ltd
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the CFSS-DS was found to be a reliable measure of child dental anxiety, and it demonstrated good internal consistency. The high reliability of the scale can be attributed to its focal characteristics and highly specific yet easily understandable questions. We found that some children were confused about the words ‘stranger’ and ‘someone’ in pilot study, and some children even thought ‘stranger’ indicated ‘ghost’. To avoid misunderstanding, the wording was changed in accordance with the expressions of the Chinese language in four items (‘Having someone examine your mouth’, ‘Having a stranger touch you’, ‘Having somebody look at you’, and ‘Having somebody put instruments in your mouth’ were changed to ‘The dentist examining your mouth’, ‘Being touched by a dentist’, ‘Being seen by a dentist’, and ‘The dentist putting instruments in your mouth’). In addition, all of the treatments are performed by dentists in China. Therefore, ‘Having the nurse clean your teeth’ was changed to ‘Having your teeth brushed by a dentist’, which is consistent with the actual clinical conditions in China. Additionally, in our study, some children could not distinguish ‘a fair amount afraid’ from ‘pretty much afraid’. We added the five drawings of faces from the FIS to the verbal scale of the CFSS-DS so that the young children could become familiar with a 5-point verbal scale. Other researchers have combined the written items from the CFSS-DS and the Modified Child Dental Anxiety Scale with five facial images, and their results provide additional evidence for the utility of facial graphics in questionnaires for young children17,19. There was also a high correlation between the Chinese version of the CFSS-DS and the ‘gold standard’ measure of child behavior, that is, the Frankl scale, which indicated the good criterion validity of this Chinese version of the CFSS-DS. Factor analyses of the CFSS-DS have been previously reported in several populations, including those in the Netherlands11, Finland9, Japan5, and India7, and in a population of Chinese children living in Canada14. The numbers of factors that emerged in the present study were in agreement with the three factors in
Dutch, Finnish, and Japanese children, although the components of the factors were different. In developed countries such as the Netherlands11, Finland9, and Japan5, the three factors that emerged were as follows: (1) fear of highly invasive dental procedures, (2) fear of the less invasive aspects of treatment, and (3) fear of medical aspects. In the present study, however, the three factors that emerged were as follows: (1) fear of dental treatment, such as choking and having to open mouth, (2) fear of hospital personnel, and (3) fear of invasive dental procedures, such as drilling and injection. Thus, although the scale has been shown to have good reliability in other studies, the personal experiences of individuals, which have major effects on their psychology, were different, which may be attributed to the cultural/environmental differences between studies. Compared to children in developed countries, children in China are less exposed to healthcare campaigns20, and they may therefore demonstrate greater fear of hospital personnel and dental care procedures, such as dentist and opening mouth7. By correctly recognizing children’s fear, we can seek to manage it effectively. Similarly to previous studies with different factor structure, some items (dentist, the dentist examining your mouth, the noise of the dentist drill, and choking) loaded (≥0.4) on more than one factor in this study, indicating a possible correlation between the extracted factors21. For example, choking loaded on both dental treatment and invasive procedures. Except for the explorative factor analysis used in most studies to assess the validity of the CFSS-DS, different methods were also used in several other studies. Lopes22 use Rasch model to validate the CFSS-DS, indicate that the 15-item scale is a multidimensional measure, and a shortened six-item scale is proposed as a valid and reliable measure of dental fear. Lee21 take higher-order factor analysis to further measure the factor structure. More research, however, is needed to verify the reliability of those methods. The mean scores of the CFSS-DS in different countries have been reported to vary from 22.1 to 35.39,10,13,15,16. The mean score
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CFSS-DS in Chinese children
of this Chinese version of the CFSS-DS was 21.0, which is closer to the lower end of the range reported by other researchers. The lower scores obtained in this study may be due to two reasons. First, this research selected school-age children between the ages of 6 and 10 years who were enrolled in primary school and possessed a certain level of cognitive ability. Many studies have shown that traumatic treatment experiences are largely responsible for the development of dental fear among children. In this study, only 15 of 206 children previously experienced painful dental treatment. Thus, it is difficult to make valid comparisons among different studies, given the differences among samples in terms of age ranges, the selection of the children (school versus hospital sample), and other factors. For example, Lee et al.15 reported very high CFSS-DS scores among children aged 2–10.5 in Taipei China. At the same time, they also found that children younger than 4 years old had significantly higher CFSS-DS scores than those in other age groups. The most feared items included the dentist drilling, the dental injection, and choking4,13,23. Along with these invasive medical procedures, prior experience of operative dental care and problematic first visits are also influential experiences related to fear24–26. In this study, children who had previously painful or extremely painful experiences exhibited significantly higher CFSS-DS scores than children without prior painful experiences. Very similar results have been reported in other studies4,13,23. Children’s fear has also been more strongly associated with the subjective experience of pain and trauma than with objective dental pathology27.Therefore, previous dental experience is an important factor in the development of fear. Several limitations of our study design should be noted. First, our sample was based on a single hospital, and the results may therefore not be representative of all children in this age group in China. Additionally, Nakai et al.5 noted that dental fear scores may be higher in school samples compared to clinic samples because children who avoid going to the dentist because of dental fear are still likely to attend school.
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In conclusion, this Chinese version of the CFSS-DS is a reliable and valid instrument to assess dental fear in children as it does in Western cultures. Additional samples of Chinese children, including school-based samples, will provide additional information about this measure.
Why this paper is important to paediatric dentists • Pediatric dentists can use the Chinese version of CFSS-DS to evaluate dental fear in children. • The results provide additional evidence that children of different cultures may fear different dental stimuli.
Conflict of interest
The authors declare no conflict of interest. References 1 Klingberg G, Broberg AG. Dental fear/anxiety and dental behaviour management problems in children and adolescents: a review of prevalence and concomitant psychological factors. Int J Paediatr Dent 2007; 17: 252–258, 391–406. 2 Frankl SN, Shiere FR, Fogels HR. Should the parent remain with the child in the dental operatory? J Dent Child 1962; 29: 14. 3 Sullivan C, Schneider PE, Musselman RJ, Dummett CO Jr, Gardiner D. The effect of virtual reality during dental treatment on child anxiety and behavior. ASDC J Dent Child 2000; 67: 160–191. 4 Cuthbert MI, Melamed BG. A screening device: children at risk for dental fears and management problems. ASDC J Dent Child 1982; 49: 432–436. 5 Nakai Y, Hirakawa T, Milgrom P et al. The Children’s Fear Survey Schedule-Dental Subscale in Japan. Community Dent Oral Epidemiol 2005; 33: 196–204. 6 Arapostathis KN, Coolidge T, Emmanouil D, Kotsanos N. Reliability and validity of the Greek version of the Children’s Fear Survey Schedule-Dental Subscale. Int J Paediatr Dent 2008; 18: 374–379. 7 Singh P, Pandey RK, Nagar A, Dutt K. Reliability and factor analysis of children’s fear survey schedule-dental subscale in Indian subjects. J Indian Soc Pedod Prev Dent 2010; 28: 151–155. 8 Aartman IH, van Everdingen T, Hoogstraten J, Schuurs AH. Self-report measurements of dental anxiety and fear in children: a critical assessment. ASDC J Dent Child 1998; 65: 252–258, 229–230. 9 Alvesalo I, Murtomaa H, Milgrom P, Honkanen A, Karjalainen M, Tay KM. The Dental Fear Survey Schedule: a study with Finnish children. Int J Paediatr Dent 1993; 3: 193–198.
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10 Klingberg G. Reliability and validity of the Swedish version of the Dental Subscale of the Children’s Fear Survey Schedule, CFSS-DS. Acta Odontol Scand 1994; 52: 255–256. 11 ten Berge M, Hoogstraten J, Veerkamp JS, Prins PJ. The Dental Subscale of the Children’s Fear Survey Schedule: a factor analytic study in The Netherlands. Community Dent Oral Epidemiol 1998; 26: 340–343. 12 Bajric E, Kobaslija S, Juric H. Reliability and validity of Dental Subscale of the Children’s Fear Survey Schedule (CFSS-DS) in children in Bosnia and Herzegovina. Bosn J Basic Med Sci 2011; 11: 214–218. 13 Wogelius P, Poulsen S, Sorensen HT. Prevalence of dental anxiety and behavior management problems among six to eight years old Danish children. Acta Odontol Scand 2003; 61: 178–183. 14 Milgrom P, Jie Z, Yang Z, Tay KM. Cross-cultural validity of a parent’s version of the Dental Fear Survey Schedule for children in Chinese. Behav Res Ther 1994; 32: 131–135. 15 Lee CY, Chang YY, Huang ST. The clinically related predictors of dental fear in Taiwanese children. Int J Paediatr Dent 2008; 18: 415–422. 16 Milgrom P, Mancl L, King B, Weinstein P. Origins of childhood dental fear. Behav Res Ther 1995; 33: 313– 319. 17 Lu JX, Yu DS, Luo W, Xiao XF, Zhao W. [Development of Chinese version of children’s fear survey schedule-dental subscale]. Zhonghua Kou Qiang Yi Xue Za Zhi 2011; 46: 218–221. 18 Buchanan H, Niven N. Further evidence for the validity of the Facial Image Scale. Int J Paediatr Dent 2003; 13: 368–369.
19 Howard KE, Freeman R. Reliability and validity of a faces version of the Modified Child Dental Anxiety Scale. Int J Paediatr Dent 2007; 17: 281–288. 20 Saekel R. China’s oral care system in transition: lessons to be learned from Germany. Int J Oral Sci 2010; 2: 158–176. 21 Lee CY, Chang YY, Huang ST. Higher-order exploratory factor analysis of the Dental Subscale of Children’s Fear Survey Schedule in a Taiwanese population. Community Dent Health 2009; 26: 183– 187. 22 Lopes D, Arnrup K, Robertson A, Lundgren J. Validating the dental subscale of the children’s fear survey schedule using Rasch analysis. Eur J Oral Sci 2013; 121: 277–282. 23 Klingberg G, Berggren U, Noren JG. Dental fear in an urban Swedish child population: prevalence and concomitant factors. Community Dent Health 1994; 11: 208–214. 24 Muris P, du Plessis M, Loxton H. Origins of common fears in South African children. J Anxiety Disord 2008; 22: 1510–1515. 25 Vogels WE, Aartman IH, Veerkamp JS. Dental fear in children with a cleft lip and/or cleft palate. Cleft Palate Craniofac J 2011; 48: 736–740. 26 Karjalainen S, Olak J, Soderling E, Pienihakkinen K, Simell O. Frequent exposure to invasive medical care in early childhood and operative dental treatment associated with dental apprehension of children at 9 years of age. Eur J Paediatr Dent 2003; 4: 186–190. 27 Townend E, Dimigen G, Fung D. A clinical study of child dental anxiety. Behav Res Ther 2000; 38: 31–46.
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Reliability and validity of the Chinese version of the Children’s Fear Survey Schedule-Dental Subscale LIN MA1, MENG WANG2, QUAN JING1, JIZHI ZHAO1, KUO WAN1 & QUN XU2 1
Department of Stomatology, Peking Union Medical College Hospital, Beijing, China, and 2Department of Epidemiology and Biostatistics, Institute of Basic Medicine Sciences Chinese Academy of Medical Sciences & School of Basic Medicine Peking Union Medical College, Beijing, China
International Journal of Paediatric Dentistry 2015; 25: 110–116 Background. The Children’s Fear Survey Schedule-
Dental Subscale (CFSS-DS) is a commonly used questionnaire that measures children’s dental fears. Aim. This study aimed to examine the reliability and validity of the Chinese version of the CFSSDS. Design. The CFSS-DS was translated into Chinese and administered to children in a dental office. The sample comprised 206 child patients aged 6–10 years, 42 of whom were selected for test– retest analysis. The behaviors of all 206 children were rated during their dental appointments and compared to their questionnaire results.
Introduction
Children commonly experience anxiety when receiving professional dental treatment, and feelings of anxiety during dental treatment can lead to uncooperative behavior that may obstruct and delay treatment. Childhood dental fear has been shown to be widespread, with a prevalence ranging from 6% to 20%, depending in part on how it is measured, the ages of the children being assessed, and the culture1. Several different methods have been used to assess dental fear in children, including behavioral ratings such as the Frankl Scale2, physiological measurements such as heart rate3, and questionnaires. Developed in 19824, the Dental Subscale of the Children’s Fear Survey Schedule (CFSSDS) is a well-known questionnaire for
Correspondence to: Prof K. Wan, Department of Stomatology, Peking Union Medical College Hospital, 1 Shuaifuyuan, Dongcheng District, Beijing 100730, China. E-mail: [email protected]
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Results. The internal consistency (Cronbach’s a) was 0.85, and the test–retest reliability (intraclass correlation) was 0.71. The Chinese version of the CFSS-DS showed good criterion validity; children who were uncooperative on the Frankl Scale had higher mean CFSS-DS scores (Z = 5.79). Through factorization, three factors emerged: (1) dental treatment, (2) hospital personnel, and (3) invasive dental procedures. Girls reported more fear than boys (21.79 vs 19.91), and children who had painful dental experiences reported more fear (30.87 vs 20.00). Conclusion. These results suggest that the CFSSDS is reliable and valid and operates in China as it does in other cultures. Further studies should include school samples to evaluate children who may not go to the dentist.
assessing dental fear in children. This scale consists of 15 items related to various aspects of dental treatment, such as injections, having to open one’s mouth, and drilling. The CFSS-DS has been widely used in recent studies and has been shown to be a valuable and adequate measure of dental fear in children5–7. In contrast to other self-reporting measurements, such as the Venham Picture Test and Dental Anxiety Scale, the CFSS-DS covers more aspects of the dental situation and measures dental fear more precisely8. The CFSS-DS has been translated into several languages and has been studied in several countries, and the results of these studies showed that the CFSSDS exhibits good internal and test–retest reliability in English as well as in several other languages5,6,9–17. Cultural differences, however, play an important role in building the psychology of a child, and scales that possess great reliability in some parts of the world may not have universal validity unless it is confirmed to be unaffected by cultural differences7. The present investigation was carried
© 2014 BSPD, IAPD and John Wiley & Sons A/S. Published by John Wiley & Sons Ltd
CFSS-DS in Chinese children
out to test the reliability and validity of a Chinese version of the CFSS-DS in the Chinese mainland. Materials and methods
Local children between the ages of 6 and 10 years attending primary school in Beijing who were seen at the Dental Department at Peking Union Medical College Hospital from June 2011 to August 2013 were recruited for this study. Children who had immigrated to Beijing from other cities, with cognitive disorders, and children with mental disorders were excluded from the study. This study was approved by the Ethics Committee of the Peking Union Medical College Hospital (No.: S-323). Parents provided written consent, and the children provided verbal assent. Development of the Chinese version of the CFSS-DS The children’s questionnaire consisted of the CFSS-DS items and a 5-point pictorial scale [Facial Image Scale (FIS)]18. The FIS consisted of five drawings of a face, displaying affective features ranging from extremely positive to neutral to extremely negative. The children were presented with the five images and asked to select the one that best corresponded to how they were feeling. The faces were scored on a scale from 1 to 5, with 1 assigned to the most positive face and 5 assigned to the most negative face. Pilot testing revealed that young children were able to answer the CFSS-DS items by referencing the facial images. To maintain consistency, all children saw the facial images during the questionnaire administration. The CFSS-DS was translated from English into Chinese by a single native speaker and subsequently back-translated by another native speaker to ensure comparability with the original form (the translation is available from the corresponding author). The Chinese version was then pre-tested in a small group of Chinese children, and the translation was modified to further ensure comparability. The dental items were summed to create an index of the child’s dental fear, with scores ranging from 15 to 75.
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Reliability study The internal reliability and criterion validity of the developed questionnaire was assessed in 206 children aged 6–10 years who were seen at the Dental Department at Peking Union Medical College Hospital. The questionnaire was completed in the waiting room of the dental practice prior to treatment. The CFSS-DS was read out loud to each child in the waiting room by one of the researchers, employing a script to introduce the survey consistently. The parents were not allowed to participate or help their children complete the questionnaire. Among the 206 children, 42 returned for dental treatment after 4 weeks. To measure test–retest reliability in these 42 children, the CFSS-DS was administered a second time to the children in the waiting room 4 weeks after the first test. Validity study During the first dental appointment, the child’s behavior was assessed by a trained observer in accordance with the Frankl Scale at several points during treatment, such as during the oral examination, upon injection, and other points. The observer was previously trained in the use of the Frankl Scale and calibrated in a previous research project. The child’s overall Frankl score was defined as his/her lowest Frankl score for any segment of treatment. The Frankl Scale consists of a 4-point scale in which 1 represents ‘definitely negative’ (e.g., the child is crying forcefully, behaving in a fearful manner), 2 represents ‘negative’ (the child is reluctant, uncooperative), 3 represents ‘positive’ (the child may be cautious but willing to comply), and 4 represents ‘definitely positive’ (the child is laughing and enjoying the situation). Children in Frankl categories 1 or 2 were combined into the negative group, and children in Frankl categories 3 or 4 were combined into the positive group. The CFSS-DS scores were unknown to the observer performing the behavior ratings. Criterion validity was assessed to examine the relationship between the CFSS-DS scores and cooperation during the dental examination and treatment.
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All 206 children were asked whether they had previous dental experience. If yes, they were asked to rate their pain in their previous treatments, with 1 representing ‘no pain at all’, 2 representing ‘a little pain or not bad’, 3 representing ‘pain’, and 4 representing ‘a lot of pain’. Children who provided a rating of ‘1’ or ‘2’ were combined into the ‘no painful experience’ group. Children who provided a rating of ‘3’ or ‘4’ were combined into the ‘painful experience’ group. The type of treatment of each child received was also recorded for all questionnaires. Children who received an examination, fissure treatment, cleaning and simple restoration were categorized as ‘non-traumatic treatment’ group, whereas those who received extraction, deep caries restoration, surgery and root canal treatment were categorized as ‘traumatic treatment’ group. Statistical analyses Data were entered into the computer and checked for accuracy. Data management and analyses were conducted using SAS/STAT, release 8.2 (SAS Institute Inc., Cary, NC, USA). Cronbach’s a was used to compute the internal consistency based on all 206 children. Intraclass correlation was used to assess the test–retest reliability of the 42 paired CFSS-DS questionnaires. Because the CFSS-DS scores were not expected to be normally distributed (most children scoring low), the Wilcoxon test was used to compare the CFSS-DS scores between ‘negative’ and ‘positive’ children, between ‘non-traumatic treatment’ group and ‘traumatic treatment’ group, and between boys and girls. The Wilcoxon test was also used to determine the relationship between types of treatment at the first appointment and the CFSS-DS scores at the second appointment. Spearman’s rho was used to determine the relationship between the CFSS-DS scores and age. A factor analysis (principal components, varimax rotation) was also employed. Results
Of the 262 eligible children, 238 children (approximately 91%) and their parents
agreed to participate in the study. A total of 206 children (114 girls and 92 boys) completed the CFSS-DS and were enrolled in this study. The children were primarily seen for root canal treatment (22.8%), simple restoration (22.3%), or deep caries restoration (21.4%), followed by extraction (12.6%), examination (12.1%), fissure treatment (4.85%), and cleaning (3.88%). The mean CFSS-DS score was 21.0 6.57 (range = 15– 55). Cronbach’s a was 0.85. Of the 42 children who completed the questionnaire twice, the test–retest reliability was 0.71 (P < 0.01). No age differences in the CFSS-DS scores were found (P > 0.05), and girls showed significantly higher scores than boys (21.79 7.06 vs 19.91 5.78, Z = 2.004, P < 0.05). For all children, as well as for boys and girls separately, the means and SDs for all items are shown in Table 1. Among the 206 children tested, six child received a score of ‘1’ (definitely negative) on the Frankl Scale, 25 children received a score of ‘2’ (negative), 90 received a score of ‘3’ (positive), and 85 received a score of ‘4’ (definitely positive). Children categorized as negative on the Frankl Scale showed significantly higher levels of dental fear on the CFSS-DS than those categorized as positive (mean scores 28.39 9.61 vs 19.63 4.83, Z = 5.79, P < 0. 01). A total of 92 children were categorized in the ‘non-traumatic treatment’ group, and 114 children were categorized in the ‘traumatic treatment’ group. There were no significant differences in type of treatment between the 206 children (20.50 6.57 vs 21.32 6.58, P > 0.05). The CFSS-DS scores of the 156 children who had experienced prior dental treatment were not different from those of the 50 children who had not had previous dental treatment (21.04 7.03 vs 20.66 4.92, P > 0.05). The CFSS-DS scores of the 15 children who were in ‘painful experience group’ were significantly higher than those of the 141 children who were in ‘no painful experience group’ (30.87 11.17 vs 20.00 5.54, P < 0.01). For the 42 children, the type of treatment at the first appointment was not related to
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Table 1. Mean Children’s Fear Survey Schedule-Dental Subscale item scores and standard deviations (SDs) for all children, boys, and girls. All children
Boys
Girls
Item
Mean
SD
Mean
SD
Mean
SD
Dentists Doctors Injections (shots) The dentist examining your mouth Having to open your mouth Being touched by a dentist Being seen by a dentist The dentist drilling The sight of the dentist drilling The noise of the dentist drilling The dentist putting instruments in your mouth Choking Having to go to the hospital People in white uniforms Having your teeth brushed by a dentist
1.35 1.25 2.18 1.19
0.63 0.60 1.32 0.56
1.29 1.22 1.99 1.15
0.52 0.61 1.22 0.49
1.40 1.27 2.34 1.23
0.70 0.60 1.39 0.61
1.26 1.23 1.19 2.17 1.29 1.44 1.29
0.72 0.69 0.61 1.90 0.67 0.90 0.65
1.25 1.20 1.11 2.02 1.18 1.29 1.29
0.66 0.47 0.40 1.20 0.53 0.73 0.72
1.27 1.26 1.25 2.28 1.37 1.55 1.28
0.76 0.82 0.73 1.17 0.76 1.00 0.59
1.59 1.29 1.05 1.18
0.90 0.72 0.27 0.51
1.54 1.17 1.02 1.17
0.88 0.52 0.15 0.53
1.62 1.38 1.08 1.19
0.92 0.82 0.33 0.50
the sum of the CFSS-DS scores at the second appointment (P > 0.05). The factor analysis pattern after varimax rotation is shown in Table 2. Three factors were identified, which together account for 53.70% of the variance. Factor I, accounting
Table 2. Rotated CFSS-DS factor matrix. Item Dentists Doctors Injections (shots) The dentist examining your mouth Having to open your mouth Being touched by a dentist Being seen by a dentist The dentist drilling The sight of the dentist drilling The noise of the dentist drilling The dentist putting instruments in your mouth Choking Having to go to the hospital People in white uniforms Having your teeth brushed by a dentist
Factor I
Factor II
Factor III
0.317 0.051 0.001 0.427
0.526 0.582 0.078 0.621
0.446 0.330 0.814 0.008
0.738 0.791 0.693 0.185 0.164
0.107 0.106 0.152 0.342 0.555
0.221 0.125 0.038 0.701 0.040
0.455
0.197
0.558
0.352
0.437
0.210
0.555 0.524
0.043 0.443
0.529 0.225
0.003 0.157
0.652 0.740
0.120 0.108
Strong factor loadings are presented in bold font.
for 35.77% of the variance, was characterized by the fear of dental treatment, including having to open your mouth, and choking. Factor II, which was characterized by the fear of hospital personnel, such as doctor, dentist, and people in while uniform, accounted for 9.80% of the variance. Factor III, which was characterized by the fear of invasive dental procedures, including drilling and injection, accounted for 8.12% of the variance. Discussion
Dental fear research in children has been carried out in a number of countries. As cultural and social norms of behavior can affect the development and expression of children’s fear, and as dental care systems can vary considerably across cultures, normative data in each culture are needed. In this study, the Chinese version of the CFSS-DS demonstrated an acceptable level of internal consistency, with a Cronbach’s a of 0.85. The internal consistency of the CFSS-DS has been reported to range from 0.85 to 0.925–7. These results further support the homogeneity of the scale, that is, that all items on the scale tap the same construct19. Therefore, this Chinese version of
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the CFSS-DS was found to be a reliable measure of child dental anxiety, and it demonstrated good internal consistency. The high reliability of the scale can be attributed to its focal characteristics and highly specific yet easily understandable questions. We found that some children were confused about the words ‘stranger’ and ‘someone’ in pilot study, and some children even thought ‘stranger’ indicated ‘ghost’. To avoid misunderstanding, the wording was changed in accordance with the expressions of the Chinese language in four items (‘Having someone examine your mouth’, ‘Having a stranger touch you’, ‘Having somebody look at you’, and ‘Having somebody put instruments in your mouth’ were changed to ‘The dentist examining your mouth’, ‘Being touched by a dentist’, ‘Being seen by a dentist’, and ‘The dentist putting instruments in your mouth’). In addition, all of the treatments are performed by dentists in China. Therefore, ‘Having the nurse clean your teeth’ was changed to ‘Having your teeth brushed by a dentist’, which is consistent with the actual clinical conditions in China. Additionally, in our study, some children could not distinguish ‘a fair amount afraid’ from ‘pretty much afraid’. We added the five drawings of faces from the FIS to the verbal scale of the CFSS-DS so that the young children could become familiar with a 5-point verbal scale. Other researchers have combined the written items from the CFSS-DS and the Modified Child Dental Anxiety Scale with five facial images, and their results provide additional evidence for the utility of facial graphics in questionnaires for young children17,19. There was also a high correlation between the Chinese version of the CFSS-DS and the ‘gold standard’ measure of child behavior, that is, the Frankl scale, which indicated the good criterion validity of this Chinese version of the CFSS-DS. Factor analyses of the CFSS-DS have been previously reported in several populations, including those in the Netherlands11, Finland9, Japan5, and India7, and in a population of Chinese children living in Canada14. The numbers of factors that emerged in the present study were in agreement with the three factors in
Dutch, Finnish, and Japanese children, although the components of the factors were different. In developed countries such as the Netherlands11, Finland9, and Japan5, the three factors that emerged were as follows: (1) fear of highly invasive dental procedures, (2) fear of the less invasive aspects of treatment, and (3) fear of medical aspects. In the present study, however, the three factors that emerged were as follows: (1) fear of dental treatment, such as choking and having to open mouth, (2) fear of hospital personnel, and (3) fear of invasive dental procedures, such as drilling and injection. Thus, although the scale has been shown to have good reliability in other studies, the personal experiences of individuals, which have major effects on their psychology, were different, which may be attributed to the cultural/environmental differences between studies. Compared to children in developed countries, children in China are less exposed to healthcare campaigns20, and they may therefore demonstrate greater fear of hospital personnel and dental care procedures, such as dentist and opening mouth7. By correctly recognizing children’s fear, we can seek to manage it effectively. Similarly to previous studies with different factor structure, some items (dentist, the dentist examining your mouth, the noise of the dentist drill, and choking) loaded (≥0.4) on more than one factor in this study, indicating a possible correlation between the extracted factors21. For example, choking loaded on both dental treatment and invasive procedures. Except for the explorative factor analysis used in most studies to assess the validity of the CFSS-DS, different methods were also used in several other studies. Lopes22 use Rasch model to validate the CFSS-DS, indicate that the 15-item scale is a multidimensional measure, and a shortened six-item scale is proposed as a valid and reliable measure of dental fear. Lee21 take higher-order factor analysis to further measure the factor structure. More research, however, is needed to verify the reliability of those methods. The mean scores of the CFSS-DS in different countries have been reported to vary from 22.1 to 35.39,10,13,15,16. The mean score
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CFSS-DS in Chinese children
of this Chinese version of the CFSS-DS was 21.0, which is closer to the lower end of the range reported by other researchers. The lower scores obtained in this study may be due to two reasons. First, this research selected school-age children between the ages of 6 and 10 years who were enrolled in primary school and possessed a certain level of cognitive ability. Many studies have shown that traumatic treatment experiences are largely responsible for the development of dental fear among children. In this study, only 15 of 206 children previously experienced painful dental treatment. Thus, it is difficult to make valid comparisons among different studies, given the differences among samples in terms of age ranges, the selection of the children (school versus hospital sample), and other factors. For example, Lee et al.15 reported very high CFSS-DS scores among children aged 2–10.5 in Taipei China. At the same time, they also found that children younger than 4 years old had significantly higher CFSS-DS scores than those in other age groups. The most feared items included the dentist drilling, the dental injection, and choking4,13,23. Along with these invasive medical procedures, prior experience of operative dental care and problematic first visits are also influential experiences related to fear24–26. In this study, children who had previously painful or extremely painful experiences exhibited significantly higher CFSS-DS scores than children without prior painful experiences. Very similar results have been reported in other studies4,13,23. Children’s fear has also been more strongly associated with the subjective experience of pain and trauma than with objective dental pathology27.Therefore, previous dental experience is an important factor in the development of fear. Several limitations of our study design should be noted. First, our sample was based on a single hospital, and the results may therefore not be representative of all children in this age group in China. Additionally, Nakai et al.5 noted that dental fear scores may be higher in school samples compared to clinic samples because children who avoid going to the dentist because of dental fear are still likely to attend school.
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In conclusion, this Chinese version of the CFSS-DS is a reliable and valid instrument to assess dental fear in children as it does in Western cultures. Additional samples of Chinese children, including school-based samples, will provide additional information about this measure.
Why this paper is important to paediatric dentists • Pediatric dentists can use the Chinese version of CFSS-DS to evaluate dental fear in children. • The results provide additional evidence that children of different cultures may fear different dental stimuli.
Conflict of interest
The authors declare no conflict of interest. References 1 Klingberg G, Broberg AG. Dental fear/anxiety and dental behaviour management problems in children and adolescents: a review of prevalence and concomitant psychological factors. Int J Paediatr Dent 2007; 17: 252–258, 391–406. 2 Frankl SN, Shiere FR, Fogels HR. Should the parent remain with the child in the dental operatory? J Dent Child 1962; 29: 14. 3 Sullivan C, Schneider PE, Musselman RJ, Dummett CO Jr, Gardiner D. The effect of virtual reality during dental treatment on child anxiety and behavior. ASDC J Dent Child 2000; 67: 160–191. 4 Cuthbert MI, Melamed BG. A screening device: children at risk for dental fears and management problems. ASDC J Dent Child 1982; 49: 432–436. 5 Nakai Y, Hirakawa T, Milgrom P et al. The Children’s Fear Survey Schedule-Dental Subscale in Japan. Community Dent Oral Epidemiol 2005; 33: 196–204. 6 Arapostathis KN, Coolidge T, Emmanouil D, Kotsanos N. Reliability and validity of the Greek version of the Children’s Fear Survey Schedule-Dental Subscale. Int J Paediatr Dent 2008; 18: 374–379. 7 Singh P, Pandey RK, Nagar A, Dutt K. Reliability and factor analysis of children’s fear survey schedule-dental subscale in Indian subjects. J Indian Soc Pedod Prev Dent 2010; 28: 151–155. 8 Aartman IH, van Everdingen T, Hoogstraten J, Schuurs AH. Self-report measurements of dental anxiety and fear in children: a critical assessment. ASDC J Dent Child 1998; 65: 252–258, 229–230. 9 Alvesalo I, Murtomaa H, Milgrom P, Honkanen A, Karjalainen M, Tay KM. The Dental Fear Survey Schedule: a study with Finnish children. Int J Paediatr Dent 1993; 3: 193–198.
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19 Howard KE, Freeman R. Reliability and validity of a faces version of the Modified Child Dental Anxiety Scale. Int J Paediatr Dent 2007; 17: 281–288. 20 Saekel R. China’s oral care system in transition: lessons to be learned from Germany. Int J Oral Sci 2010; 2: 158–176. 21 Lee CY, Chang YY, Huang ST. Higher-order exploratory factor analysis of the Dental Subscale of Children’s Fear Survey Schedule in a Taiwanese population. Community Dent Health 2009; 26: 183– 187. 22 Lopes D, Arnrup K, Robertson A, Lundgren J. Validating the dental subscale of the children’s fear survey schedule using Rasch analysis. Eur J Oral Sci 2013; 121: 277–282. 23 Klingberg G, Berggren U, Noren JG. Dental fear in an urban Swedish child population: prevalence and concomitant factors. Community Dent Health 1994; 11: 208–214. 24 Muris P, du Plessis M, Loxton H. Origins of common fears in South African children. J Anxiety Disord 2008; 22: 1510–1515. 25 Vogels WE, Aartman IH, Veerkamp JS. Dental fear in children with a cleft lip and/or cleft palate. Cleft Palate Craniofac J 2011; 48: 736–740. 26 Karjalainen S, Olak J, Soderling E, Pienihakkinen K, Simell O. Frequent exposure to invasive medical care in early childhood and operative dental treatment associated with dental apprehension of children at 9 years of age. Eur J Paediatr Dent 2003; 4: 186–190. 27 Townend E, Dimigen G, Fung D. A clinical study of child dental anxiety. Behav Res Ther 2000; 38: 31–46.
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