Who will pass the dental OSCE? Comparison of the Angoff and the borderline regression standard setting methods.

AIM: Aim of this study is to elucidate which standard setting method is optimal to prevent incompetent students to pass and competent students to fail a dental Objective Structured Clinical Examination (OSCE). MATERIAL AND METHODS: An OSCE with 14 test stations was used to assess the performance of 119 third year dental students in a training group practice. To establish the pass/fail standard per station, three standard setting methods were applied: the Angoff I method, the modified Angoff II with reality check and the Borderline Regression (BR) method. For the final decision about passing or failing the complete OSCE, three methods were compared: total compensatory (TC), a partial compensatory (PC) within clusters of competence and a non-compensatory (NC) model. The reliability of the pass/fail standard of the three methods was indicated by the root mean square error (RMSE). As a criterion measure, a sample of the students (n = 89) was rated in the clinic by their instructors and accordingly these students were divided into two groups: competent and incompetent students. The students' clinical rating (considered for this study as 'true qualification') was compared with the pass-fail classification resulting from the OSCE. Undeserved passing of an incompetent student was considered as more damaging than failing a competent student. RESULTS: The BR method showed more acceptable results than the two Angoff methods. In terms of pass rate the BR method showed the highest pass rates: for the TC model the Angoff method I and II and the BR showed pass rates of 86.6%, 86.6% and 97.5% respectively. For the PC model the pass rates were 30.3%, 34.5% and 61.3%, and for the NC model the pass rates were 0.8%, 1.7% and 7.6%. The BR method showed lower RMSEs (higher reliability): for the TC model the RMSEs were 1.3%, 1.0% and 0.3% for the Angoff I, Angoff II and BR method respectively, and for the PC model the RMSE of the clusters of competence range was 2.0-3.7% for Angoffs I; 1.8-2.2% for Angoff II and 0.6-0.7% for the BR method. In terms of incorrect decisions, the BR method had a higher loss due to incorrect decisions for the TC model than for the PC model which is in accordance with the results of other studies in medical education. CONCLUSIONS: Therefore we conclude that the BR method in a PC model provides defensible pass/fail standards and seems to be the optimal choice for OSCEs in health education.

On the reliability of a dental OSCE, using SEM: effect of different days.

AIM: The first aim was to study the reliability of a dental objective structured clinical examination (OSCE) administered over multiple days, and the second was to assess the number of test stations required for a sufficiently reliable decision in three score interpretation perspectives of a dental OSCE administered over multiple days. MATERIALS AND METHODS: In four OSCE administrations, 463 students of the year 2005 and 2006 took the summative OSCE after a dental course in comprehensive dentistry. The OSCE had 16-18 5-min stations (scores 1-10), and was administered per OSCE on four different days of 1 week. ANOVA was used to test for examinee performance variation across days. Generalizability theory was used for reliability analyses. Reliability was studied from three interpretation perspectives: for relative (norm) decisions, for absolute (domain) and pass-fail (mastery) decisions. As an indicator of reproducibility of test scores in this dental OSCE, the standard error of measurement (SEM) was used. The benchmark of SEM was set at <0.51. This is corresponding to a 95% confidence interval (CI) of <1 on the original scoring scale that ranged from 1 to 10. RESULTS: The mean weighted total OSCE score was 7.14 on a 10-point scale. With the pass-fail score set at 6.2 for the four OSCE, 90% of the 463 students passed. There was no significant increase in scores over the different days the OSCE was administered. 'Wished' variance owing to students was 6.3%. Variance owing to interaction between student and stations and residual error was 66.3%, more than two times larger than variance owing to stations' difficulty (27.4%). The SEM norm was 0.42 with a CI of +/-0.83 and the SEM domain was 0.50, with a CI of +/-0.98. In order to make reliable relative decisions (SEM <0.51), the use of minimal 12 stations is necessary, and for reliable absolute and pass-fail decisions, the use of minimal 17 stations is necessary in this dental OSCE. CONCLUSIONS: It appeared reliable, when testing large numbers of students, to administer the OSCE on different days. In order to make reliable decisions for this dental OSCE, minimum 17 stations are needed. Clearly, wide sampling of stations is at the heart of obtaining reliable scores in OSCE, also in dental education.

Language background and OSCE performance: a study of potential bias.

AIM: To investigate whether Non-Native dental students perceive drawbacks in their education and examination experience because of their lack of language proficiency and to test whether prolonging Objective Structured Clinical Examination (OSCE) test-station duration improves their performance. MATERIALS AND METHODS: Dental students (n = 345) completed a questionnaire about their native country, their language background and the possible drawback they perceived in dental education and examination because of their language proficiency. Students were marked as 'native', when they were born in the Netherlands with Dutch as native language or 'Non-Native' when they were born outside the Netherlands, raised with a non-Dutch native language, or raised bilingually. A sample of 108 students was assessed by an OSCE testing a periodontal course with nine test-stations. Test-station topics were: (1) history taking, (2) measuring attachment level, (3) educating patients, (4) tracing a radiograph, (5) root-planing, (6) writing a prescription, (7) diagnostics and prognostics, (8) differential diagnostics and (9) writing a referral letter. The first five test-stations mentioned were of 5-min duration. The other four test-stations were provided in two modes: either with a short (5 min) or longer (10 min) version. Every student took at random two long and two short test-stations. RESULTS: In the group of 345 questionnaire responders, Non-Native students (n = 116) perceived significantly more drawback in education and examination than Native students (n = 229) (P < 0.001). When Non-Native students speak Dutch at home, around 38% of them reported perceived drawbacks in education, whereas when they speak their native language at home, around 60% reported perceived drawbacks in education (P = 0.005). In the periodontal OSCE (n = 108), the Native group (n = 70) had significantly higher total scores than the Non-Native (n = 38), (P = 0.009, d = 0.53). The Non-Native group had significantly lower mean scores in the communication station 'educating patients' (P = 0.034, d = 0.42). Prolonged test-station duration from 5 to 10 min had no positive effect in all experimental test-stations in the Native and Non-Native group. Female students in the Native group out-performed male in a communication test-stations. Female students in Native and Non-Native groups were found to be more successful in 'tracing bone loss on radiographs'. CONCLUSION: Non-Native students perceived a drawback in dental education and examination because of their language proficiency in Dutch, which is confirmed by their actual OSCE performance. Prolonging the time for a test-station did not improve OSCE performance of Non-Native students. It is recommended that students with problems in language ability need additional tuition and practice.

Epigenetic alterations complement mutation of JAK2 tyrosine kinase in patients with BCR/ABL-negative myeloproliferative disorders.

An acquired autoactivating mutation with a V617F amino-acid substitution in the JAK2 tyrosine kinase is frequently found in BCR/ABL-negative myeloproliferative disorders (MPD). Hypermethylation of CpG islands within gene promoter regions is associated with transcriptional inactivation and represents an important mechanism of gene silencing in the pathogenesis of hematopoietic malignancies. In this study, we determined the DNA methylation status of 13 cancer-related genes in the context of JAK2 mutations in 39 patients with MPD. Genes analyzed for hypermethylation were SOCS-1, SHP-1, E-cadherin, MGMT, TIMP-2, TIMP-3, p15, p16, p73, DAPK1, RASSF1A, RARbeta2 and hMLH1. We found at least one hypermethylated gene in 15/39 MPD patient specimens, and in 6/39 samples aberrant methylation of the negative cytokine regulator SOCS-1 was present. The JAK2V617F mutation was found in 21/39 patients as determined by allele-specific polymerase chain reaction. Hypermethylation of SOCS-1 was observed in 3/21 patients with an autoactivating JAK2 mutation and in 3/18 patients with wild-type JAK2. Our results suggest that epigenetic inactivation of SOCS-1 may be a complementary mechanism to the JAK2V617F mutation in the pathogenesis of MPD that leads to dysregulation of JAK-STAT signal transduction and thus contributes to growth factor hypersensitivity.

Implementing an Objective Structured Clinical Examination (OSCE) in dental education: effects on students' learning strategies.

OBJECTIVES: To investigate the effect of an Objective Structured Clinical Examination (OSCE) on dental students' learning strategies and competence to manage periodontal diseases in patients. The implemented OSCE was expected to be superior to the existing Written Exam in fostering the acquisition of clinical competencies in terms of study strategies that are more oriented towards clinical practice, longer study time, greater clinical proficiency, and more realistic self-assessment. MATERIAL AND METHODS: After a clinical course in periodontology, 72 third year dental students were assessed summatively, either using a Written Exam or an OSCE (P-OSCE). The students were informed beforehand about the assessment formats. The self-assessed clinical competence, study time and strategies (i.e. practice with a manikin, peers and patient case) were evaluated by means of a questionnaire. After a comprehensive dental care course, all 72 students were assessed by an overall end-of-year OSCE, in which three periodontal stations were included 'measuring pockets', 'educating patients' and 'tracing an X-ray with bone-loss'. The competence of the previous Written Exam group and the P-OSCE group was investigated by determining the mean scores and pass-fail scores of three periodontal test-stations as well as the total score of the end-of-year OSCE. The degree of realistic self-assessment was studied by correlating the self-assessed competencies as evaluated by means of the questionnaire with the total score of the end-of-year OSCE. RESULTS: Self-assessed clinical competence, study time and study strategies showed no differences between the P-OSCE and the Written Exam-group. The clinical competence determined in the test-station 'measuring pockets' in the end of year overall OSCE was higher for the P-OSCE group (P = 0.05) when compared with the Written Exam group; the two groups performed equally well in the test station 'educating patients', whereas the performance in 'tracing an X-ray with bone-loss' was better in the Written Exam group. This group also had a higher total score in the end-of-year OSCE (P = 0.05). The degree of realistic self-assessment was higher in the P-OSCE group than in the Written Exam group: in the P-OSCE group the self-assessed clinical competencies correlated significantly with the total score of the overall end-of-year OSCE (P < or = 0.05). CONCLUSIONS: No effects of the implementation of an OSCE in undergraduate periodontal education were observed in study strategies, but the implementation of an OSCE in undergraduate periodontal education appears to stimulate learning, resulting in greater achievement of specific clinical competence and a greater level of realistic self-assessment.

An implementation strategy for introducing an OSCE into a dental school.

INTRODUCTION: The Objective Structured Clinical Examination (OSCE) uses a series of test-stations to test clinical competencies. The introduction of an OSCE in a dental school is always a new experience for both staff and students and may result in a change in assessment methods. As resistance could develop when changes are introduced into an organisation, the use of a strategy for the implementation of such change will help to diminish opposition and may therefore result in the co-operation of staff and their departments. The objective of this study was to investigate the effectiveness of an implementation strategy by measuring attitudes of both staff and students towards the OSCE as a new form of clinical assessment in a dental school (ACTA). MATERIALS AND METHODS: 'Stepwise' behaviour change (with information, participation and commitment as tools) was used as a strategy to minimise protective behaviour to the introduction of an OSCE. After lectures on assessment, 59 staff members participated in a mini-OSCE with eight test-stations, playing both the role of a student and observer. A questionnaire, designed to test attitudes and commitment towards the new OSCE was completed after the examination. Six months later, 22 staff of all departments had developed and run a pilot OSCE for 44 students. A similar questionnaire was answered by staff and students. A year later, another OSCE for all 103 third year students was designed, organised and evaluated with full co-operation of the clinical teaching staff. RESULTS: Staff total attitude grew positively (P = 0.001). Student's total attitude was lower than staff (P < 0.001) The results of the survey after the mini-staff-OSCE and pilot and final OSCE were favourable in terms of the acceptance of use of an OSCE for the assessment of clinical competences. CONCLUSION: The implementation strategy appears to have been successful. The objective of gaining the co-operation of staff and departments and avoiding resistance to change was achieved.

Is there a relationship between head posture and craniomandibular pain?

An often-suggested factor in the aetiology of craniomandibular disorders (CMD) is an anteroposition of the head. However, the results of clinical studies to the relationship between CMD and head posture are contradictory. Therefore, the first aim of this study was to determine differences in head posture between well-defined CMD pain patients with or without a painful cervical spine disorder and healthy controls. The second aim was to determine differences in head posture between myogenous and arthrogenous CMD pain patients and controls. Two hundred and fifty persons entered the study. From each person, a standardized oral history was taken and blind physical examinations of the masticatory system and of the neck were performed. The participants were only included into one of the subgroups when the presence or absence of their symptoms was confirmed by the results of the physical examination. Head posture was quantified using lateral photographs and a lateral radiograph of the head and the cervical spine. After correction for age and gender effects, no difference in head posture was found between any of the patient and non-patient groups (P > 0.27). Therefore, this study does not support the suggestion that painful craniomandibular disorders, with or without a painful cervical spine disorder, are related to head posture.

A systematic review of the relationship between overjet size and traumatic dental injuries.

The aim of this study was to aggregate the risk of traumatic dental injury due to overjet using several published papers and performing a meta-analysis on the results. The 11 articles involved in this investigation were identified by a literature search of Medline (1966-1996) and Exerpta Medica (1985-1996) databases using predetermined keywords, and inclusion and exclusion criteria. In order to assess the quality of each paper, a methodological checklist for observational studies was developed resulting in a score between 0 and 100. The relative risk of overjet, compared with a reference, was expressed as an Odds Ratio (OR). For each study, the OR was computed using the data presented and, subsequently, these ORs were pooled across studies. The effect of confounders (i.e. age, gender), which could bias the relationship between overjet and dental injury was taken into account. Furthermore, the influence of quality of the study on the pooled OR was addressed. The average methodological score was 41. From the results, it can be concluded that children with an overjet larger than 3 mm are approximately twice as much at risk of injury to anterior teeth than children with an overjet smaller than 3 mm. The effect of overjet on the risk of dental injury is less for boys than for girls in the same overjet group. In addition, risk of injury of anterior teeth tends to increase with increasing overjet size. Furthermore, the pooled OR does not seem to be affected by the quality of the studies.

Interposed bone grafts to accommodate endosteal implants for retaining mandibular overdentures. A 1-7 year follow-up study.

The results are reported on 34 edentulous patients, who underwent interposed autogenous bone graft augmentation in the symphysis of the mandible, combined with bone-hydroxylapatite onlay augmentation of the area posterior to the mental foramina. Two to four implants were placed in the grafted symphysis after 3-5 months. An overdenture was constructed three months later. The follow-up period ranged from one to seven years. An average loss of mandibular bone height of 10-13% was observed. The data provided no evidence of a further time-dependent resorption from two-and-half to seven years.

[Dental research in the Netherlands. Citations in publications]. / Tandheelkundig onderzoek in Nederland. Citaties van publicaties.

This study examines the citation frequency (via the Science Citation Index) of publications by Dutch dental scientists that have appeared in the international literature since World War II. It was found that most citations were obtained by a relatively small group of researchers, many of them working in the fields of cariology and periodontology. High scores were particularly found among scientists who had their academic training in disciplines other than dentistry. Out of 109 frequently cited papers over 25% was microbiology-oriented and most of them could be characterized as original basic dental research.

Quantification of facial morphology using stereophotogrammetry--demonstration of a new concept.

OBJECTIVES: The purpose of this study was to introduce stereophotogrammetry as a three-dimensional registration method for quantifying facial morphology and detecting changes in facial morphology during growth and development. METHODS: Using stereophotogrammetry, three-dimensional (3-D) co-ordinates for the bilateral landmarks Exocanthion and Cheilion and the midsagittal landmark Pronasale were determined in 10 subjects to ascertain the reproducibility of the method, and in 59 children to detect changes in facial morphology due to growth and development. Linear and angular measurements were calculated by means of the 3-D co-ordinates in order to quantify facial morphology. Significant differences were determined by means of analyses of variance (MANOVA). RESULTS: During the observation period, significant (P < 0.01) changes in facial morphology were determined for the linear measurements. Advantages and disadvantages of current registration methods are discussed. CONCLUSION: It is concluded that stereophotogrammetry is a suitable 3-D registration method for quantifying and detecting developmental changes in facial morphology.

[Dental research in the Netherlands: Ph.D theses 1956-1994]. / Tandheelkundig onderzoek in Nederland: dissertaties 1956-1994.

The number of PhD-theses by Dutch scientists shows a continuous increase over the last four decades, resulting in about 20 theses per year during the early nineties. They cover a wide range of subjects in all major disciplines of dental research and nowadays are usually written in English (in 80% of the cases). A substantial proportion (23%) of all dental theses comes from scientists not trained as dentist but in other disciplines like biochemistry and psychology. So far, the drastic decline in the number of Dental Schools in the Netherlands during the eighties has had little influence on the overall outcome of PhD-theses. The international impact of Dutch dental research seems to increase over the years as shown by the declining fraction of Dutch dental scientists who are never cited in the international dental literature.

Longitudinal study on three-dimensional changes of facial asymmetry in children between 4 to 12 years of age with unilateral cleft lip and palate.

The purpose of the present study was to describe three-dimensional developmental changes of facial asymmetry in children with an operated complete unilateral cleft lip and palate (UCLP) and in children without craniofacial anomalies (controls). Using stereophotogrammetry, three-dimensional coordinates for 16 bilateral and 10 midsagittal facial landmarks were determined for the UCLP group (n = 33) and the control group (n = 63) on two occasions. In this mixed-longitudinal study, the children were 4 to 12 years of age. Facial asymmetry and left-right dominance was measured and resolved for transverse, vertical, and sagittal components. Significant effects were analyzed with multivariate analyses of variance (MANOVA). We concluded that individuals with complete unilateral cleft lip and palate, as well as individuals without craniofacial anomalies, show an increase, during growth, in the amount of facial asymmetry in the basal region of the nose. In the region that is related to the cleft, children with complete unilateral cleft lip and palate do not show changes in the amount of facial asymmetry between the occasions. Regarding facial left-right dominance and variation in dominance, no demonstrable growth changes take place in individuals with complete cleft lip and palate, nor in individuals without craniofacial anomalies.

[Dental research in the Netherlands: an international orientation]. / Tandheelkundig onderzoek in Nederland: een plaatsbepaling.

Analysis of dental scientific literature (section Dentistry & Odontology of the Science Citation Index) has revealed that the majority of the contributions to dental science come from the USA, the UK and Japan. Also Dutch scientists showed up as active contributors, especially when viewed against the distribution of IADR-members and dental practitioners over the world. The scientific output in the Netherlands is evenly spread over the various dental subdisciplines, although some emphasis is seen on the fields of cariology and social dentistry.

Spatial and morphologic aspects of temporomandibular joints with sounds.

Various spatial and morphological aspects of the temporomandibular joint may be involved in the development of TMJ sounds. The present study examines their contribution to the prediction of sounds. A non-patient sample was studied using sensitive sound measurement and panoramic radiography. It was found that temporomandibular joint sounds are common in asymptomatic subjects showing substantial variation in several spatial and morphological parameters. An autonomous contribution of spatial relationships, asymmetries or morphology of bony structures to the prediction of joint sounds could not be detected. When unilateral sounds were present, they were more likely to be found on the side with the less steep condylar movement path. Joint imaging is not indicated in the detection of relationships between bony structures and their eventual asymmetries and joint sounds.

Method for quantifying facial asymmetry in three dimensions using stereophotogrammetry.

A three-dimensional method to quantify facial asymmetry is introduced. Stereophotogrammetry was applied to determine three-dimensional (3-D) coordinates for eight pairs of surface landmarks of 106 individuals, including 16 with an operated complete unilateral cleft lip and palate. Facial asymmetry was quantified from four different reference planes that were defined perpendicular to and bisecting lines between pairs of bilateral landmarks related to the eyes, nose and mouth. Significant differences (P < 0.01) between these four planes were determined using multivariate analyses of variance (MANOVA). It is concluded that the best reference plane to select in studies of facial asymmetry is formed by the one which is perpendicular to and bisects the line that connects the landmarks Exocanthion. Reproducibility and validity of the method is demonstrated.

Facial left-right dominance in cleft lip and palate: three-dimension evaluation.

Studies on facial left-right dominance in individuals without craniofacial anomalies have demonstrated controversial results. This is probably due to the frequent use of two-dimensional methods, yet left-right dominance consists of transverse, vertical, and sagittal components. The aim of the present study was to describe three-dimensionally facial left-right dominance in individuals with an operated complete unilateral cleft lip and palate on the left side (LUCLP), on the right side (RUCLP), and in individuals without craniofacial anomalies (controls). Using stereophotogrammetry, three-dimensional coordinates for 16 bilateral and 10 midsagittal facial landmarks were determined for the LUCLP group (N = 32), the RUCLP group (N = 17), and the control group (N = 80). Left-right dominance was measured in three directions. Individuals without craniofacial anomalies showed a facial left sided dominance in the transverse direction, a facial right sided dominance in the sagittal direction, and no particular dominated side in the vertical direction. Individuals with a unilateral cleft lip and palate demonstrated a facial dominance of the nonaffected side in the vertical direction as well as in the sagittal direction, with no particular side dominant in the transverse direction. Generally, there was more variation in left-right dominance within the face in the vertical and sagittal directions.

Three-dimensional evaluation of facial asymmetry in cleft lip and palate.

The purpose of the present study was to describe facial asymmetry in three dimensions in individuals with an operated complete unilateral cleft lip and palate (UCLP) and in individuals without craniofacial anomalies (controls). Three-dimensional coordinates for 16 bilateral and 10 midsagittal facial landmarks were determined for the UCLP group (N = 49) and the control group (N = 80) by means of stereophotogrammetry. The total asymmetry was measured and resolved for transverse, vertical, and sagittal components. It can be concluded that all three components are important in studies on facial asymmetry. Individuals with UCLP show more facial asymmetry in the vertical direction than controls. They demonstrate more facial asymmetry in the region related to the cleft than controls. And, males in general demonstrate more asymmetry of the nose than females.

The relation between periodontitis and systemic bone mass in women between 46 and 55 years of age.

It has been suggested that periodontitis and systemic bone mass might be related. In order to evaluate this possible relationship, we performed an intra-oral examination and measured lumbar bone mineral density (lumbar BMD) and metacarpal cortical thickness (MCT) in 286 female volunteers between 46 and 55 years of age. In addition, the alveolar bone height was measured on bite wing radiographs of the dentate subjects. Of the subject, n = 60 (21%) were edentulous. Compared to the dentate subjects, the lumbar BMD and MCT of the edentulous women were not significantly different. In the dentate subjects, no significant correlation was observed between the clinical parameters of periodontitis (mean probing depth, occurrence of bleeding after probing and number of missing teeth) and the bone mass parameters (lumbar BMD and MCT); nor was a significant relation observed between the bone mass measurements and alveolar bone height. We therefore suggest that systemic bone mass is not an important factor in the pathogenesis of periodontitis.