Psychometric evaluation of the Lebanese Arabic version of the Dental Fear Survey: a cross-sectional study

Abstract

Background Dental fear is a prevalent problem that can lead to poor dental health. The Kleinknecht’s Dental Fear Survey (DFS) is one of the used scales to assess dental fear. The present study aims to evaluate the psychometric properties of the Lebanese Arabic version of the DFS (DFS-A) and to determine the optimal cut-off to identify dental fear as well as the correlates of dental fear in a group of Lebanese adults dental patients. Methods A cross-sectional study was conducted among a group of 442 dental patients (18–65 years) recruited at 29 dental clinics from March to June 2019. Patients completed a questionnaire including questions about demographic characteristics, previous bad dental experience, trauma’s experience period, the sensation of nausea during dental treatment, the DFS-A scale, the Lebanese Arabic version of the Modified Dental Anxiety Scale (MDAS-A), and a general question about dental fear. Results DFS-A revealed evidence of adequate psychometric properties. DFS-A scale demonstrated high internal consistency (cronbach’s alpha = 0.93). Test–retest reliability assessment demonstrated strong reproducibility of the DFS-A scale score (ICC = 0.92 with 95% CI (0.83–0.96), p value < 0.0001 (N = 30). Confirmatory factor analysis revealed a three-factor structure of the DFS-A reflecting fear associated with specific dental stimuli and procedures, patterns of dental avoidance and anticipatory anxiety, and physiologic arousal during dental treatment. A significant correlation was found between DFS-A and the MDAS-A indicating a good convergent validity. The optimal cut-off point to identify patients with and without dental fear is 41. Considering this cut-off score, the prevalence of dental fear in our sample was reported at 33.8%. Multivariable analysis showed that having previous scary and painful dental experiences, a sensation of nausea during treatment, and having dental anxiety were identified as predictors of dental fear. Conclusion The adapted Arabic version of the DFS (DFS-A) is a valid tool to evaluate dental fear among Lebanese adult patients.

Validation of the "obturator functioning scale" for Chinese-speaking patients with obturator prostheses after cancer-related maxillectomy

“…Considering the 15 items of the OFS, 75 to 150 participants should be required according to the sample size guidance that 5–10 participants per scale item would be suitable to establish sufficient evidence of scale validity and reliability [ 16 ]. In this study, a total sample size of 133 was considered appropriate for testing the proposed model.…”

“…Internal consistency reliability was determined by Cronbach's coefficient α for the total scale and each subscale. A coefficient of over 0.7 indicated acceptable internal consistency [ 16 , 24 ]. Test-retest reliability was evaluated by calculating Spearman's correlation between the first and second assessments on 41 patients.…”

“…However, the OFS remains a scale without formal measures of validity in any language until now, partly because maxillary cancer is a relatively rare tumour with high mortality [ 2 ]. In fact, the number of samples in these studies involved in measuring the reliability of OFS is within the range of 30–57 patients [ 7 , [12] , [13] , [14] , [15] ], not meeting the criterion with a minimum of five participants per scale item to evaluate the construct validity [ 16 ].…”