Comparison of resident performance in interpreting mammography results using a probabilistic or a natural frequency presentation: a multi-institutional randomized experimental study.

BACKGROUND: Residents are being increasingly challenged on how best to integrate diagnostic information in making decisions about patient care. The aim of this study is to assess the ability of residents to accurately integrate statistical data from a screening mammography test in order to estimate breast cancer probability and to investigate whether a simple alteration of the representation mode of probabilities into natural frequencies facilitates these computations. METHODS: A multi-institutional randomized controlled study of residents was performed in eight major hospitals in the city of Athens. Residents were asked to estimate the positive predictive value of the screening mammography test given its sensitivity and 1-specificity as well as the prevalence of breast cancer in the relevant population. One version of the scenario was presented in the single-event probability format that is commonly used in the medical literature, while the other used the natural frequency representation. The two questionnaire versions were randomly assigned to the participants. RESULTS: Out of 200 residents, 153 completed and returned the questionnaire (response rate 76.5%). Although more than one-third of the residents reported excellent or close to excellent familiarity with sensitivity and positive predictive value, the majority of responses (79.1%) were incorrect. However, a significantly higher proportion of residents in the natural frequency group (n = 88) selected the correct response compared with residents (n = 65) in the single-event probability group (28.4% vs 10.8%; 95% confidence intervals of the difference between the two proportions = 5.6-29.7%; P < 0.01). DISCUSSION: Residents more often correctly understand test performance accuracy when test characteristics are presented to them as natural frequency representations than the more common approach of presenting single event probabilities. Educators and journal editors should be aware of this facilitative effect.

Assessment of cognitive biases and biostatistics knowledge of medical residents: a multicenter, cross-sectional questionnaire study.

PURPOSE: The aim of this study is to determine the perceived familiarity of medical residents with statistical concepts, assess their ability to integrate these concepts in clinical scenarios, and investigate their susceptibility to the gambler's fallacy and the conjunction fallacy. METHODS: A multi-institutional, cross-sectional survey of Greek medical residents was performed. Participants were asked to indicate their familiarity with basic statistical concepts and answer clinically oriented questions designed to assess their biostatistics knowledge and cognitive biases. Univariate, bivariate, and multivariate statistical models were used for the evaluation of data. RESULTS: Out of 153 respondents (76.5% response rate), only two participants (1.3%) were able to answer all seven biostatistics knowledge questions correctly while 29 residents (19%) gave incorrect answers to all questions. The proportion of correct answers to each biostatistics knowledge question ranged from 15 to 51.6%. Residents with greater self-reported familiarity were more likely to perform better on the respective knowledge question (all p<0.01). Multivariate analysis of the effect of individual resident characteristics on questionnaire performance showed that previous education outside Greece, primarily during medical school, was associated with lower biostatistics knowledge scores (p<0.001). A little more than half of the respondents (54.2%) answered the gambler's fallacy quiz correctly. Residents with higher performance on the biostatistics knowledge questions were less prone to the gambler's fallacy (odds ratio 1.38, 95% confidence intervals 1.12-1.70, p=0.003). Only 48 residents (31.4%) did not violate the conjunction rule. CONCLUSIONS: A large number of medical residents are unable to correctly interpret crucial statistical concepts that are commonly found in the medical literature. They are also especially prone to the gambler's fallacy bias, which may undermine clinical judgment and medical decision making. Formalized systematic teaching of biostatistics during residency will be required to de-bias residents and ensure that they are proficient in understanding and communicating statistical information.

Endothelial progenitor cells (EPCs) and mesenchymal stem cells (MSCs) in bone healing.

Fracture healing is a complex physiological process. Local vascularity at the site of the fracture has been established as one of the most important factors influencing the healing process, and lack of vascularity has been implicated in atrophic non unions. Existing research has primarily involved utilising Mesenchymal Stem Cells (MSCs) to augment bone healing but there remains much scope to explore the role of stem cells in the vascularisation process. Endothelial Progenitor Cells (EPCs) and other Endothelial Cellular populations (ECs) could constitute a valid alternative to MSCs. This systematic review is examining the importance of co-implantation of MSCs and EPCs/ECs for bone healing. A literature search was performed using the Cochrane Library, OVID Medline, OVID EMBASE and Google Scholar, searching for combinations of the terms EPCs, Endothelial progenitor cells, angiogenesis, fracture, bone and healing. Finally 18 articles that fulfilled our criteria were included in this review. ECs could be of value for the treatment of critical size bone defects as they are known to be capable of forming ectopic, vascularised bone. The co-implantation of ECs with MSCs is more intriguing when we take into account the vast array of complex reciprocal interactions between ECs and MSCs.

The effort-reward imbalance questionnaire in Greek: translation, validation and psychometric properties in health professionals.

OBJECTIVES: The aim of the present study was to translate, adapt and validate the Effort-reward imbalance (ERI) questionnaire in a sample of Greek healthcare professionals. METHODS: An internationally recommended methodology was followed to perform translation of the ERI instrument into the Greek language. The questionnaire was then randomly administered to 600 Greek physicians, nurses, physiotherapists and laboratory staff, and 456 questionnaires with no missing data on the ERI items were returned (76% response rate). Tool validation included assessment of internal consistency, factorial structure, discriminant validity and presence of floor or ceiling effects. Criterion validity was demonstrated by investigating the association of theoretically relevant ERI summary measurements with respondents' self-rated health. RESULTS: The Greek version of the ERI questionnaire showed good psychometric properties. Cronbach's alpha values were 0.79, 0.72 and 0.75 for the three ERI scales of effort, reward and overcommitment respectively. Exploratory factor analysis yielded a 5-factor solution that closely reflected the original theoretical ERI model. Significant associations were found between respondents' age, gender and specific occupation with ERI scores. ERI ratio and "overcommitment" scores in the highest tertiles were associated with elevated odds ratios (OR) of below-average self-rated health (OR=5.38, 95% confidence intervals 1.77 to 16.38, p=0.003, and OR=3.41, 95% confidence intervals 1.39 to 8.38, p=0.007, respectively). CONCLUSIONS: The translated and adapted Greek version is comparable with the original ERI instrument in terms of validity and factorial structure and is suitable for assessment of the psychosocial work environment of Greek healthcare professionals.

Burnout and training satisfaction of medical residents in Greece: will the European Work Time Directive make a difference?

BACKGROUND: The aim of this study is to determine the prevalence of burnout in Greek medical residents, investigate its relationship with training satisfaction during residency and survey Greek medical residents' opinion towards the European Work Time Directive (EWTD). METHODS: A Multi-centre, cross-sectional survey of Greek residents was performed. The Maslach Burnout Inventory (MBI) was used to measure burnout, which was defined as high emotional exhaustion, combined with high depersonalization or low personal accomplishment. In addition, seven questions were designed for this study to evaluate self-reported resident training satisfaction and three questions queried residents' opinion on the EWTD and its effects on their personal and social life as well as their medical training. Univariate, bivariate and multivariate statistical models were used for the evaluation of data. RESULTS: Out of 311 respondents (77.8% response rate), 154 (49.5%) met burnout criteria and 99 (31.8%) indicated burnout on all three subscale scores. The number of residents that were dissatisfied with the overall quality of their residency training were 113 individuals (36.3%). Only 32 residents (10.3%) believed that the EWTD implementation will not have any beneficial effects for them. CONCLUSIONS: Both burnout and training dissatisfaction were common among Greek residents. Systemic interventions are thus required within the Greek health system, aimed at reducing resident impairment due to burnout and at improving their educational and professional perspectives. Although residents' opinion on the EWTD was not associated with burnout levels, the EWTD was found to be predominantly supported and anticipated by Greek residents and should be implemented to alleviate their workload and stress.

Greek medical students' career choices indicate strong tendency towards specialization and training abroad.

The aim of the study was to investigate the career choices, location preferences and criteria among medical students in Greece. We applied a questionnaire-based analysis using a sample of 591 students of four out of seven Greek Medical Schools. The sample included students of all academic years. The vast majority of students wish to specialize (97.6%), while general practice gathered a very low percentage (1.7%). The scientific challenge (61.4%) and interaction with patients (60.6%) seem to be the major influencing factors for most of the students' specialty preferences, whilst less common variables influencing career choice are the high demand/supply ratio for certain health services (40.4%), the income potential (31.4%), the active tempo (26.2%) and prestige (15%). 70.3% of those asked consider the possibility of specializing abroad. The low concern of Greek medical students for general practice reveals today's drastic deficiency in Greek primary health care. Such a situation will escalate, unless targeted strategies to produce more general practitioners are adopted. Furthermore, the results reflect a lower education and organizing level urging students to specialize abroad. The National Health System (NHS) should be reformed towards a rationalistic distribution of the medical specialties and medical workforce.