Evaluation of the Sources of Stress in Dominican Dental Students: a cross-sectional study

Background The dentistry practice has long been considered a highly stressful health-science profession. Stress in dental students has been addressed by a number of international studies, but it has never been studied specically in students in the Dominican Republic. The purpose of this cross-sectional study is to evaluate the sources of stress in Dominican dental students so as to establish a link between said stressors, and school term and sex. Methods For measurement purposes, a survey (our modied Dental Environment Stress (DES) questionnaire) was conducted on 103 dental students pursuing clinical practica. We analyzed our data using a one-way ANOVA, t-test, factor analysis and VARIMAX. Results All dental students in their nal six terms of school suffered stress, with the 12th term ranking highest. The sources of stress differed among students in varying terms. Exams, fear of failing, interaction with teaching staff, as well as responsibilities associated with patient care, obtained the most points. Women obtained greater scores in certain items when compared to the academic factor. Conclusions The various sources of stress act independently in dental students, with those with greater values being exams, fear of failing subjects, different assessment criteria among teaching staff, responsibilities associated with patient care, fear of failing a term and job prospects. Women demonstrated a more acute response to stress with regards to the academic factor, end of university studies and self-esteem.


Background
The dentistry practice has long been considered a highly stressful health-science profession. [1][2][3][4] The academic training of dentists involves a variety of events, which may spur primary emotions (such as fear, disgust, surprise, anger, happiness, sadness, etc.), cognitive attitudes (anxiety) and psychological processes (stress).
Individuals are constantly required to adapt to the ever-evolving demands of their work environment. To do so, they must undergo allostasis, or the process of achieving internal stability. This biological process involves activating one's resources to face both predictable and unpredictable events. Stress appears when a given situation is perceived as threatening or dangerous. In the case of stress, additional resources are required to help the individual in question decide whether the situation is a false alarm, calls for an immediate response, or evokes emotions and experiences. This learning process will assist the individual in anticipating future events. 5 The term stress was introduced by Selye 6 as the organism's non-speci c response to any demand (source of stress). A source of stress is any stimulus, external or internal (physical, chemical, acoustic, somatic or socio-cultural), that destabilizes the internal balance of the organism in a direct or indirect way. 7 The psychological implications of these sources vary among individuals, and personal characteristics will condition one's vulnerability to stress.
Stress in dental students has been addressed by a number of international studies, [2][3][4][8][9][10][11][12][13][14][15][16][17][18][19][20] but it has never been studied speci cally in students in the Dominican Republic. The coexistence of several potentially stressful factors, including relationships between students, professors, patients and administrative staff, may bear an impact on dental students. Previous authors have approached stress in dental students through detection and measurement of the sources generating stress; 9,21-23 the student's vulnerability due to his or her own life and personality; 24 the appearance of clinical manifestations; 25 interactive models of the agents that co-occur in the development of such stress; 26 and behavior-modi cation techniques that may help students mitigate stress. 27 Dental education programs in the Dominican Republic consist of 12 terms and are divided into two periods: a basic period covering general, pre-clinical courses, and a second, professional period including clinical practica. Previous studies show that the peak onset of stress generally appears in the transition from pre-clinical courses to clinical ones, or the second period of the program. [28][29][30] This clinical component could be of great relevance in terms of stress generation.
The present study is relevant because, according to the literature, no previous studies had been conducted on dental students in the Dominican Republic. We were also interested in evaluating the potential correlation between the varying sources of stress. When stressors are exposed, direct intervention is made possible, with the ultimate goal being to eliminate or relieve the negative effects of said stressors on students. It could also be helpful to teach students behaviour-modi cation techniques, so that they are better equipped to confront stress in the future.

Sample
One hundred and three undergraduate students (80 women, 23 men) from Federico Henriquez y Carvajal University participated in the present study. The students volunteered to take part in the study, which was conducted anonymously. The personal information obtained was age, sex and school term. Of the 103 clinical students, 31 were in their sixth term, 36 were in their ninth term, and 36 were in their twelfth term. The participants had a mean age of 21.86 years (Standard Deviation, S.D., 1.53).

Measuring Instruments
A modi ed Dental Environment Stress (DES) questionnaire was used for evaluation (Tables 1 and 2). It consists of 58 items following a Likert-type scale (1. Not stressful, 2. Slightly stressful, 3. Moderately stressful, 4. Very stressful, 5. Extremely stressful). This questionnaire was based on the Dental Environment Stress questionnaire, 21 although we included new items gathered from bibliographical review and personal interviews conducted randomly with students. This new questionnaire was submitted to an expert committee for validation. The questionnaire response rate was 96%.

Procedure and Statistical Analysis
Once the committee had validated the questionnaire, we obtained the licenses required from the Dentistry Department of the Faculty of Health Sciences, Federico Henriquez y Carvajal University, to begin this cross-sectional study. Assessments took place during an exam-free period. Initially, students were unaware as to why they were meeting with us, but upon arrival, an instructor explained the purpose of the survey in general terms, and they then proceeded to provide consent before lling out the questionnaire.
All data analyses were conducted using SPSS version 24.0 (SPSS Inc., Chicago, IL). A descriptive analysis of the averages and frequencies was carried out, as was an analytical analysis using one-way ANOVA, t-test, factor analysis and VARIMAX.

Results
In the mean modi ed DES analysis, we discovered that the main stressors were ( Table 3) The term producing the highest level of stress was the 12th (M=2.85), followed by the 6th (M=2.82) and the 9th (M=2.81). Comparing the mean modi ed DES scores for each item, we found that there were signi cant statistical differences (p<0.05) in each term ( Table 4).
Review of the mean modi ed DES scores regarding sex yielded signi cant differences (particularly among women), as seen in Table 5.
Due to the large number of items under study, a factor analysis was carried out to determine whether the variables in question demonstrated correlation. The program grouped the items into 10 dimensions or factors as per correlation. Following this analysis, the dimensions were named accordingly (Tables 6-15: factor analysis).
After this step, the various dimensions were examined to determine the weight of each with regard to stress generation. This was completed using VARIMAX (Table 16).
We observed that the items were grouped into ten factors explaining 57.40% of the total variance. Taking into account the mean values, the academic factor was identi ed as the most relevant in terms of stress, followed by the atmosphere in the clinic and personal insecurities. The t-test (Table 17) yielded relevant differences for the academic factor, end of university studies and self-esteem, where women obtained the highest score.

Discussion
The greatest di culty we encountered when evaluating stress levels in dental students was the wide range of potentially stressful sources or stressors. 31 In this study, we measured potentials sources of stress in Dominican students pursuing courses with clinical practica, as previous studies concluded that factors causing dental students signi cant stress were relationships with patients, administrative and support staff, as well as the professors of the clinical practica. 21,28,29,[32][33][34][35] Authors like Alhajj et al 9 and Alzahem et al 2 have added that stress levels increase progressively the farther along a student is in the program. In this study, students in their 12 th term demonstrated the highest stress levels, obtaining signi cant values for items referencing proximity to end of program, nal exams, increased interaction with patients, and teaching and admin staff, 29,30 insecurity about the job market, lack of con dence in future as a dentist without professor supervision, and even doubts as to their true calling. Abu-Ghazaleh et al have highlighted the importance of family expectations with regard to academic success. 8 Other studies [11][12][13][14]16,20 yet have stated that clinical requirements are signi cant stressors. The present study did not take this item into account, as it was not part of the clinical evaluation. As for increased uncertainty and insecurity, 34 students may very well experience anticipatory anxiety because of it, although it generally tends to subside with experience. 36, 37 Other authors have found that anticipatory anxiety sets in in the third term, when students are rst exposed to patients. 11,12,16,18,20,23,35,38,39 With regard to sex, our data shows greater stress levels in women, with signi cant differences for certain items ( Table 3). As for the bibliography reviewed, women, as a rule, demonstrated greater values across varying scales. 4,19,20 However, a number of studies 8,9 posit that this could in fact be cultural in nature, claiming that women in the populations studied are more likely to be open about their feelings, whereas men are more likely to bottle up their emotions when faced with challenges. 9 Conversely, other authors claim that, 12,29,30 generally speaking, men present greater stress levels, while Inquimbert et al a rmed in 2017 that there are no signi cant differences between the sexes. 17 When analyzing the total mean value of each speci c item in the present study, we found that the exams item obtained the highest score (M: 4.44, S.D.: 0.652). Table 2. Generally speaking, evaluations can provoke intense stress levels in students and require a high level of responsiveness, 22,[40][41][42][43] given that they must pass said exams to complete the terms and program. These results coincide with numerous works published in the literature that establish that exams and evaluations are among the top ve most stressful factors faced by students. 2,3,8,9,11,14,[16][17][18] Grades alone may also generate stress, as there is generally a fair amount of competition associated with them. 44 The item with the second-highest score in our research was fear of failing, which may be linked to poor test results, carrying out a clinical procedure incorrectly or facing the consequences of said error, as well as clashes with parents. 3 These results coincide with other studies that have placed this element among the top ve most stressful factors faced by dental students. 9,18,20,34 Professors play a key role in ensuring the quality of treatments patients receive and alleviating any discomfort they may suffer. 45 Some students believe that professors are, at times, a source of considerable stress, 2 as they receive contradictory instructions from them when treating patients. 9,11 This leads to lowered self-esteem in students when required to make clinical decisions, and increased mental distress. 46 Students observe that their professors are not consistent in their ways, and that their requests are not always reasonable. As a result of this, students may adopt a passive attitude, and attempt to y below the radar. This may compromise students' progress, as obtaining passing grades becomes their only focus. 21 In response to this, Muirhead and Locker concluded that it would be helpful to train clinical staff and attempt to unify evaluation criteria to minimize this source of stress. 39 Conversely, authors like Fonseca et al 13 and Ersan et al 12 believe varying staff criteria and the environment created by clinical professors to be irrelevant as a source of stress in students.
In the vast majority of surveys, there is no allusion made to the fact that variables are correlated using factor analysis, and that groups may have been established in an arbitrary way. In our survey, factor analysis followed by VARIMAX enabled us to group together and score the sources of stress across ten dimensions, which, however, could not explain 100% of the stress generated (as with Sanders and Lushington, 46 also using VARIMAX). This occurs because stress is a multidimensional concept with variables acting independently in each individual. Yet we can a rm that the academic factor is the most relevant stressor, as re ected in other studies. 22,35,40,41,47,48 That being said, this factor is not exclusive, as it interacts with others. If a student fails his or her exams, he or she will not pass their courses, will have to face their parents and professors after a failing grade, and may have subsequent personal problems (daily life factor), as described by Yap et al. 40 Furthermore, the atmosphere in the clinic item is essential to distinguishing the rst period from the second, and re ects the transition from basic sciences to clinical sciences. 47 The fact that the responsibilities associated with patient management scored higher in our sample than the opinions that patients may have regarding the treatments received suggests that what actually causes stress among dental students is carrying out treatments, not patient management per se. Students' inexperience and professors' high expectations may increase treatment-related stress.
The primary obstacle we encountered during this study was the potential subjective nature of the responses given. In order to validate the tools applied here, we suggest carrying out a multicentric study in all of the dental schools in the Dominican Republic.

Conclusions
The various sources of stress act independently in dental students, with those with greater values being exams, fear of failing subjects, different assessment criteria among teaching staff, responsibilities associated with patient care, fear of failing a term and job prospects. Women demonstrated a more acute response to stress with regards to the academic factor, end of university studies and self-esteem.
Further research about speci c sources of stress should incorporate multicentric surveys within Dominican universities to standardize criteria (survey results show great dispersion). We would also like to highlight the need for a proper assessment of teaching staff, so as to establish a consensus regarding theory/practice issues arising in their courses. A protocol for treatment proceedings in the university clinic should also be put in place. Finally, offering dental students the option to take part in workshops about anxiety and stress management, and urging dental institutions to develop surveys alongside psychology professionals, may lead to further improvements. Approval was obtained for this study from Federico Henriquez y Carvajal University´s institutional review board. Written consent was obtained from all participants.

Consent for publication.
Not applicable.

Availability of data and material
The data and material are available from the corresponding author.

Competing interests
The authors declare that they have no competing interests.