*Maria Dubielecka1, Ewa Rusyan1, Mariusz Panczyk2, Agnieszka Mielczarek1
A preliminary assessment of the usefulness of the Polish language version of MDAS scale for the estimation of dental treatment anxiety levels among adults in Warsaw
Wstępna ocena wykorzystania polskiej wersji językowej skali MDAS w badaniu poziomu lęku przed leczeniem stomatologicznym u dorosłych mieszkańców Warszawy
1Department of Conservative Dentistry, Medical University of Warsaw
Head of Department: Agnieszka Mielczarek, MD, PhD
2Department of Teaching and Outcomes of Education, Medical University of Warsaw
Head of Department: Joanna Gotlib, DHSc
Wstęp. Lęk przed leczeniem stanowi jedną z podstawowych przeszkód w zgłoszeniu się do lekarza stomatologa osób, które wymagają takiego leczenia. Stąd w leczeniu stomatologicznym istotne jest użycie skutecznej i nieskomplikowanej metody oceny poziomu lęku. MDAS (Modified Dental Anxiety Scale) to krótki, składający się z 5 pytań kwestionariusz. Pacjent ma do wyboru jedną z 5 możliwych odpowiedzi na każde pytanie. Otrzymane wyniki pozwalają lekarzowi na obiektywną ocenę lęku stomatologicznego u pacjenta i dzięki temu ułatwiają skuteczne leczenie.
Cel pracy. Celem pracy była ocena przydatności polskiej wersji językowej skali MDAS w badaniu nasilenia lęku przed leczeniem stomatologicznym u dorosłych mieszkańców Warszawy.
Materiał i metody. W badaniu wzięło udział 126 osób obojga płci (M = 50, K = 76). W badaniu zastosowano zaadoptowaną skalę MDAS oceny nasilenia lęku. Wyboru odpowiedzi dokonywano w pięciostopniowej skali Likerta. Uzyskane wyniki podlegały sumowaniu w granicach 5-25 punktów: 0-5 – brak lęku, 6-10 – małe nasilenie lęku, 11-18 – lęk o dużym nasileniu, powyżej 19 punktów – bardzo silny poziom lęku stomatologicznego. Do analizy wyników zastosowano test Manna-Whitneya-Wilcoxona oraz χ2 Pearsona i dokładny test Fishera. Współczynnik alfa-Cronbacha, test sferyczności Bartletta i indeks Kaisera-Mayera-Olkina zostały użyte do oceny skali MDAS. Obliczenia wykonano z użyciem pakietu STATISTICA wersja 12.5 (StatSoft, Inc.). Przyjęty poziom istotności wynosił p = 0,05.
Wyniki. Ocena parametrów psychometrycznych wykazała, że skala MDAS jest rzetelna (współczynnik alfa-Cronbacha 0,792), jednowymiarowa i charakteryzuje się odpowiednią trafnością kryterialną i teoretyczną. W badanej grupie ankietowanych powyżej 35. roku życia było dwukrotnie więcej osób z brakiem lęku w porównaniu z grupą < 35. roku życia (23,64 vs. 12,67%). Osoby starsze częściej wykazywały silny lęk niż osoby młodsze (25,45 vs. 9,86%). Występowanie bardzo silnego lęku (≥ 19 punktów) stwierdzono u 3,2% badanych (n = 4). Porównując poziom nasilenia lęku w czterostopniowej skali (0-5, 6-10, 11-18 i ≥ 19), w dwóch grupach wiekowych zaobserwowano, że istnieje istotna zależność w tym zakresie (χ2 Yates = 8,53; df = 3; p = 0,036). Nie stwierdzono istotnych różnic pod względem występowania bardzo silnego lęku stomatologicznego (MDAS ≥ 19) u kobiet i mężczyzn (dokładny test Fishera; p = 0,151) oraz w grupach wiekowych (χ2 Yates = 0,16; df = 1; p = 0,690).
Wnioski. Zastosowanie skali MDAS daje możliwość szybkiej i obiektywnej oceny występowania i stopnia nasilenia lęku stomatologicznego u pacjenta, co ułatwia planowanie leczenia i wybór metody postępowania terapeutycznego. W populacji dorosłych mieszkańców Warszawy tylko niewielki odsetek pacjentów charakteryzuje bardzo silny lęk przed leczeniem stomatologicznym, wymagający profesjonalnej pomocy psychiatrycznej i psychologicznej. Lekarz stomatolog dysponując odpowiednią wiedzą i umiejętnościami w zakresie ograniczenia lęku u pacjenta, ma możliwość wdrożenia skutecznej terapii u osób, u których poziom lęku oceniono w skali MDAS poniżej 19 punktów.
Introduction. Fear of treatment is one of the main obstacles that prevent patients requiring this type of intervention from attending dental appointments. Hence the importance of a simple and effective method for the assessment of anxiety levels. MDAS (Modified Dental Anxiety Scale) is a short questionnaire consisting of 5 questions. The patient is asked to choose one of the 5 possible answers to each question. The received score allows the doctor to perform an objective assessment of patient’s dental anxiety and to implement effective treatment.
Aim. The aim of the study was to estimate the usefulness of the Polish version of MDAS scale in the assessment of dental anxiety levels among adults in Warsaw.
Material and methods. A total of 126 adult patients participated in the study (M = 50, F = 76). MDAS scale was adopted for dental anxiety level estimation. Available responses were registered in a 5-point Likert scale. The scores were summarised within the range of 5-25 points: 0-5 – no anxiety, 6-10 – minimum level of anxiety, 11-18 – high level of anxiety, and over 19 – extremely high level of dental anxiety. Chi2 and the Mann-Whitney-Wilcoxon and the Fisher’s tests were used for the analysis of anxiety level within the groups. Cronbach’s coefficient alpha, spherical Bartell test and Kaiser-Meyer-Olkin Measure of Sampling were implemented to assess the MDAS scale. Calculations were performed using STATISTICA ver. 12.5 (StatSoft, Inc.). The accepted level of significance was p = 0.05.
Results. The evaluation of psychometric parameters showed that the MDAS scale used in the study is reliable (Cronbach’s coefficient alpha 0.792), unidimensional and can be characterised by criterial and theoretical accuracy. There were twice more patients who declared no dental anxiety in the group of patients > 35 years old compared to the group of patients < 35 years old (23.64 vs. 12.67%). Elderly patients tended to show anxiety more often than younger participants (25.45 vs. 9.86%). An extremely high anxiety level (19 or higher) was found in 3.2% of participants (n = 4). A comparison of the level of anxiety in a four-item scale (0-5, 6-10, 11-18, and ≥ 19) in both age groups demonstrated a significant relationship in this regard (χ2 Yates = 8.53; df = 3; p = 0.036). There were no significant differences in relation to the occurrence of extremely high levels of dental anxiety neither in regard to gender (MDAS ≥ 19) (Fisher’s test; p = 0.151) nor age (χ2 Yates = 0.16; df = 1; p = 0.690).
Conclusions. The use of the MDAS allows for a more efficient and objective evaluation of the occurrence and the level of dental anxiety, which facilitates both treatment planning and the choice of a therapeutic method. Only a small percentage of patients from the adult population of Warsaw showed extremely high levels of dental anxiety, which requires professional psychiatric and psychological support. A dentist with appropriate knowledge and skills in decreasing the level of patient’s anxiety is able to implement effective treatment even in individuals diagnosed with anxiety level of over 19 according to the MDAS scale.
Dentists often encounter patients with a varying severity of dental anxiety in their practice. Severe symptoms of anxiety are colloquially referred to by doctors as dental phobia (1). Knowledge on the definitions of fear, anxiety and phobia is necessary for appropriate dental anxiety level assessment. It is also needed for the choice of a method to manage these phenomena (2).
Fear is an element of a natural body’s alarm system, which is necessary to avoid dangerous situations. Considering the predictable consequences, this is a logical and appropriate response to a known, specified threat. The definition of anxiety is more complicated. Anxiety is a negative emotional state associated with the anticipation of danger approaching from the outside or the inside of one’s body, which is manifested as apprehension, tension or the sense of threat. As opposed to fear, anxiety is an internal process unrelated to a direct danger or pain. It is in a sense pointless body’s mobilisation, which occurs in response to thoughts, ideas, other’s opinions or words rather than a real danger (3). This is accompanied by symptoms of autonomic arousal in response to danger, which is unspecified and doubtful.
The following adaptive mechanisms are triggered in a situation of danger:
– release of fear hormone, allowing to concentrate on managing in a dangerous situation (atavism),
– elevated blood pressure – congestion of muscles, pale skin,
– increased demand for energy – the liver increases glucose levels; increased demand for oxygen – increased breathing rate, shallow breath,
– removal of excess heat from the body by sweating, evaporation – drying of the mucous membranes,
– increased blood clotting,
– dilation of pupil for better vision (4).
During this time, the brain collects and processes data to answer questions such as how real the danger is or whether I will be able to deal with this danger.
Dental phobia is a persistent, pathological, unreasonable strong fear of certain objects or situations. Even when patients realise the groundlessness of their fear, they are unable to eliminate it, which impairs their everyday functioning. Like other phobias, dental fear belongs to mental disorders and mental function impairments (DSM V, ICD10) (5). Unfortunately, there is only one Polish phrase, i.e. „to be afraid of”, which is commonly used to describe patient’s behaviour in each of the above mentioned cases, which contributes to a certain freedom in using this phrase when describing a given condition. Fear is the most common feeling in dental patients (17-50%). Anxiety is much less common, affecting approx. 10% of patients. Dental phobia occurs in only a small proportion of patients (3-10%, depending on the source) (6). Both, anxiety and dental phobia cause patients to avoid dental appointments, which is associated with the permanent deterioration in oral health. Therefore, the problem of treating patients with strong dental anxiety becomes extremely important. Armfield described a phenomenon known as a „vicious circle”, which involves constantly increasing health problems due to increasing dental anxiety and avoidance of treatment (7). Additionally, treatment of patients with anxiety is much more difficult for dentists. It is stressful, requires a lot more time and often ends in failure e.g. due to an incorrect assessment of pulp vitality (8). Fear of the dentist makes patients attend dental appointments only in the case of extremely severe pain. They usually choose extractions, thus losing more teeth.
Aetiology of the fear of the dentist and dental procedures
Negative patient’s experiences are the most common cause of the fear of the dentist and dental procedures. While the memory of experienced pain or an injury seems reasonable, the search for the cause of patient’s anxiety in humiliating and indifferent treatment by medical personnel or past sexual abuse is less obvious, though confirmed in the literature. Disturbing images and information acquired from one’s environment (parents, films) can also trigger anxiety. There is also a theory of genetically encoded information to avoid injury or puncture, which is stored in human consciousness. The list of causes of dental anxiety is long and often surprising from the point of view of the doctor.
Studies showed that patients are afraid of:
– anaesthesia injection,
– the awareness of the use of a needle by the dentist,
– numbness after anaesthesia,
– disease transmission through tissue injury,
– a procedure „within the face and mouth”,
– choking, aspiration,
– allergy to analgesics,
– embarrassment due to the poor condition of the oral cavity,
– the need to take and maintain a supine position,
– embarrassing behaviour- making a fool of oneself,
– panic attack,
– lack of control over situation,
– therapeutic complications,
– undergoing treatment procedures considered unnecessary by the patient,
– poor aesthetic effect,
– high, unpredictable costs of treatment (9).
Milgrom classified patients into 4 groups, depending on the source of anxiety (The Seattle System developed at the University of Washington):
1. patients whose anxiety is stimulated by specific objects, sounds and smells that may be found in a dental setting (the sight of tools, the sound of devices, the smell of medications),
2. patients whose anxiety results from the distrust of dental personnel,
3. patients with generalised dental anxiety,
4. patients with fear of catastrophe (10).
Appropriate assessment of anxiety severity is necessary for successful dental treatment of affected patients. Only on this basis it is possible to develop an individualised treatment plan, taking into account methods for anxiety reduction (relaxation, behavioural methods, control reinforcement – tell-to-show, cognitive therapy) (11). Scales which allow to determine the level of anxiety in a patient-friendly manner (single choice answer to a varying number of questions) have been introduced for this purpose.
The most commonly used scales for adult patients include Corah Dental Anxiety Scale – DAS (4 questions), Modified Dental Anxiety Scale – MDAS (5 questions), Dental Fear Assessment Scale – DFAS (31 answers), Kleinknecht Dental Fear Scale – DFS (20 questions) (12).
1. A preliminary assessment of selected qualitative parameters of the Polish language version of MDAS questionnaire.
2. An assessment of the occurrence and severity of dental anxiety among adult patients in Warsaw.
3. An assessment of the potential effects of sex and age on the level of anxiety associated with a dental appointment.
Material and methods
The study was conducted using the MDAS questionnaire among the residents of Warsaw who visited the stand of the Department of Conservative Dentistry during a medical picnic organised by the Medical University of Warsaw in 2015. A total of 150 respondents, who declared their age in four ranges: 18-25 years, 26-34 years, 35-54 years and over 55 years, participated in the study. Since 24 questionnaires were not fully completed, the final group of 126 respondents were qualified for the study. The study group included 76 women and 50 men. For further analysis, the group was divided into 2 age subgroups: < 35 year-old and ≥ 35 year-old respondents.
The MDAS scale used in the study was a DAS scale modified by Humphris et al. in 1995 (12). The modification involved an addition of item 5, referring to anaesthesia injection.
The MDAS questionnaire includes 5 questions:
1. If you went to your dentist for treatment tomorrow, how would you feel?
2. If you are sitting in the waiting room, how do you usually feel?
3. If you are about to have a tooth drilled, how do you feel?
4. If you are about to have your teeth scaled and polished, how do you feel?
5. If you are about to have a local anaesthetic injection, how do you feel?
The respondent chooses one of the possible answers, which are scored as follows:
– not anxious (a score of 1),
– slightly anxious (a score of 2),
– anxious (a score of 3),
– very anxious (a score of 4),
– extremely anxious (a score of 5).
The total score is a sum of all five items, and the result for a given respondent is within the range of 5 to 25. A score of 5 indicates the absence of anxiety, a score of 6-10 indicates mild anxiety, while a score of 11-18 indicates severe anxiety. A score of above 19 indicates extreme anxiety and classifies the patient to the group of individuals with dental phobia. The use of MDAS questionnaire for each patient before dental treatment allows for a simple and objective assessment of the occurrence and severity of anxiety.
According to the art. 37al (Journal of Laws 2001 No. 126, item 1381) (13), questionnaires, retrospective and other non-invasive (non-interventional) studies do not require the approval of the Bioethics Committee.
We used selected methods for the analysis of reliability and accuracy in accordance with Sullivan’s guidelines for the assessment of the psychometric properties of MDAS scale (14). The validation procedure was based on two criteria for the assessment of scale reliability: (a) analysis of statistical characteristics of test items (internal conformity assessment, Cronbach alpha coefficient); and (b) analysis of the relationship between the score for each scale item and a summed score for each scale (discriminatory power) (15). According to Nunnally’s criterion, the level of reliability of at least 0.600 was considered as acceptable for Cronbach alpha coefficient (16). The discriminatory power was determined to estimate the interscale compatibility of different statements, and a correlation value of at least 0.300 was accepted as a criterion for sufficient discrimination (15). Exploratory factor analysis was used for the assessment of theoretical accuracy of MDAS, also referred to as internal accuracy. We checked whether the assumptions of this analytical method were fulfilled: we estimated the degree of variance homogeneity, calculated the correlation matrix determinant, measured sampling adequacy, i.e. the Kaiser-Meyer-Olkin (KMO) index, as well as performed the Bartlett’s sphericity test. We assessed whether the factor structure of MDAS consists of one element, which should correspond to theoretical assumptions. For this purpose, we used the Kaiser criterion, which assumes that the designated eigenvalues should exceed 1 only once, and the degree of restoration of indicator variable variation by the first main component should exceed 40% (17, 18).
Non-parametric tests were used to estimate the potential differences in the level of anxiety in the group of women and men as well as in the group of patients below the age of 35 years and older respondents (≥ 35 years). In the case of quantitative variables, the Mann-Whitney-Wilcoxon test or the Kolmogorov-Smirnov test was used for comparisons between groups. The choice of the test depended on whether the condition of scale parameter equality was met in both compared groups. For this purpose, the Ansari-Bradley test for the assessment of the equality of dispersion parameters was used. In the case of dispersion inequality, the Kolmogorov-Smirnov test was used for comparisons (19). For variables expressed in a nominal scale, the Pearson’s χ2 test or Fisher’s exact test was used for comparisons. We also checked whether the Cochrane’s condition was met to ensure the correctness of conclusions (20).
All calculations were performed using the STATISTICA 12.5 version package (StatSoft, Inc.), in accordance with the license of the Medical University of Warsaw. A default level of significance p = 0.05 was accepted for all analyses.
Results of psychometric analysis
When assessing the internal conformity of the measurement performed using the MDAS scale, the value of Cronbach alpha reliability coefficient, which was 0.792 (after standardisation 0.800), was estimated. The obtained result confirmed the fulfilment of the minimum Nunnally’s criterion for psychometric scale reliability.
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1. De Jongh A, Aartman IHA, Brand N: Trauma-related phenomena in anxious dental patients. Community Dent Oral Epidemiol 2003; 31: 58-58. 2. Armfield JM, Heaton LJ: Management of fear and anxiety in the dental clinic: a review. Aust Dent J 2013; 58: 390-407. 3. Armfield JM: How do we measure dental fear and what are we measuring anyway? Oral Health Prev Dent 2010; 8: 107-115. 4. Appukuttan DP: Strategies to manage patients with dental anxiety and dental phobia: literature review. Clin Cosmet Investig Dent 2016; 8: 35-50. 5. Beaton L, Freeman R, Humphris G: Why are people afraid of the dentist? Observations and Explanations. Med Princ Pract 2014; 23: 295-301. 6. Carter AE, Carter G, Boschen M et al.: Pathway of fear and anxiety in dentistry: a review. World J Clin 2014; 2(11): 642-653. 7. Armfield JM: What goes around comes around: revisiting the hypothesized vicious cycle of dental fear and avoidance. Community Dent Oral Epidemiol 2013; 41: 279-287. 8. Eli I: Dental anxiety: a cause for possible misdiagnosis of tooth vitality. Int Endod 1993; 26(4): 251-253. 9. Armfield JM, Milgrom P: A clinical guide to patients afraid of dental injections and numbness. SAAD Dig 2011; 27: 33-39. 10. Milgrom P: Treating fearful dental patient: a patient management handbook. Reston (Va). Reston Public Co 1985. 11. Peltier B: Psychological treatment of fearful and phobic special needs patient. Spec Care Dentist 2009; 29(1): 51-57. 12. Humphris GM, Morrison T, Lindsay SJ: The Modified Dental Anxiety Scale: validation and UK norms. Community Dent Health 1995; 12: 143-150. 13. Dz. U. 2001, nr 126, poz. 1381, art. 37al. 14. Sullivan GM: A primer on the validity of assessment instruments. J Grad Med Educ 2011; 3(2): 119-120. 15. Jankowski K, Zajenkowski M: Methods for estimating the reliability of the measurement. [In:] Fronczyk K (ed.): Psychometrics – basic problems. Vizja Press & IT, Warszawa 2009: 84-110. 16. Nunnally JC, Bernstein IH: Psychometric theory. 3rd ed. Vol. 226. McGraw-Hill, New York 1967. 17. Kaiser HF: The varimax criterion for analytic rotation in factor analysis. Psychometrika 1958; 23(3): 187-200. 18. Yeomans KA, Golder PA: The Guttman-Kaiser criterion as a predictor of the number of common factors. The Statistician 1982; 31: 221-229. 19. Sheskin D: Handbook of Parametric and Nonparametric Statistical Procedures. 4th ed. Chapman and Hall/CRC, Boca Raton, Florida 2004. 20. Sharpe D: Your Chi-Square Test is Statistically Significant: Now What? Pract Assess Res Eval 2015; 20(8): 1-10. 21. Gatchell RJ, Ingersoll BD, Bowman L et al.: The prevalence of dental fear and avoidance a recent survey study. J Am Dent Assoc 1983; 107(4): 609-610. 22. Armfield J: The avoidance and delaying of dental visits in Australia. Aust Dent J 2012; 57: 1-5. 23. Dailey Y, Humphris G, Lennon M: Reducing patients’ state anxiety in General Dental Practice: a randomized controlled trial. J Dent Res 2002; 81(5): 319-321. 24. Bahammam MA, Hassan MH: Validity and reliability of an Arabic version of MDAS in Saudi adults. Saudi Med J 2014; 35(11): 1384-1389. 25. Sitheeque M, Massoud M, Yahya S, Humphris G: Validation of the Malay version of the MDAS and prevalence of dental anxiety in Malaysian population. J Investig Clin Dent 2015; 6: 313-320. 26. Coolidge T, Hillstead MB, Farjo N et al.: Additional psychometric data for the Spanish MDAS and psychometric data for Spanish version of Revised Dental Beliefs Survey. BMC Oral Health 2010; 10: 12. 27. Mărginnean I, Filimon L: Modified dental anxiety scale: a validation study on communities from the west part of Romania. IJEPC 2012; 2(1): 102-114. 28. Coolidge T, Arapostathis KN, Emmanouil D et al.: Psychometric properties of Greek version of the Modified Corah Dental Anxiety Scale (MDAS) and the Dental Fear Survey (DFS). BMC Oral Health 2008; 8: 29. 29. Tunc EP, Firat D, Onur OD, Sar V: Reliability and validity of the Modified Dental Anxiety Scale (MDAS) in a Turkish population. Community Dent Oral Epidemiol 2005; 33: 357-362. 30. Humphris G, Dyer TA, Robinson PG: The modified dental anxiety scale: UK general public population norms in 2008 with further psychometrics and effects of age. BMC Oral Health 2009; 9: 20. 31. Yuan S, Freeman R, Lahti S et al.: Some psychometric properties of the Chinese version of the MDAS with cros validation. Health Qual Life Outcomes 2008; 6: 22. 32. Pohjola V, Lahti S, Vehkalahti MM et al.: Association between dental fear and dental attendance among adults in Finland. Acta Odontol Scand 2007; 65(4): 224-230. 33. Humphris GM, Freeman R, Campbell J et al.: Further evidence for the reliability and validity of the MDAS. Int Dent J 2000; 50: 367-370. 34. Humphris G, Crawford JR, Hill K et al.: UK population norm for the MDAS with percentile calculator: adult dental health survey 2009 results. BMC Oral Health 2013; 13: 29. 35. Schienle A, Scharmüller W, Leutgeb V et al.: Sex differences in the functional and structural neuroanatomy of dental phobia. Brain Struct Funct 2013 May; 218(3): 779-787. DOI: 10.1007/s00429-012-0428-z. 36. Schienle A, Köcher A, Leutgeb V: Frontal late positivity in dental phobia: A study on gender differences. Biol Psychol 2011; 88: 263-269. 37. John MT: Dental anxiety is considerably associated with pain experience during dental procedures. J Evid Base Dent Pract 2013; 20(3): 29-30. 38. Rayman S, Dincer E, Almas K: Managing dental fear and anxiety. N Y State Dent J 2013; 29: 25-29.