Exploring mechanisms underlying learning from deliberate reflection: An experimental study.

INTRODUCTION: Previous research suggests that, relative to generating a differential diagnosis, deliberate reflection during practice with clinical cases fosters learning from a subsequently studied scientific text and promotes interest in the subject matter. The present experiment aimed to replicate these findings and to examine whether motivational or cognitive mechanisms, or both, underlie the positive effects of reflection. METHODS: A total of 101 5th-year medical students participated in an experiment containing four phases: Students (a) diagnosed two clinical cases of jaundice-related diseases either through deliberate reflection or differential diagnosis; (b) reported their situational interest and awareness of knowledge gaps; (c) studied a text about jaundice, either under free or restricted time; and (d) recalled the text. Outcome measures were text-recall, situational interest and awareness of knowledge gaps. RESULTS: A main effect of diagnostic approach on recall of the text was found, with the reflection group recalling more studied material than the differential diagnosis group (means: 72.56 vs 58.80; P = .01). No interaction between diagnostic approach and study time (free or restricted) emerged, nor was there a main effect of the latter. Relative to the differential diagnosis group, students who reflected upon the cases scored significantly higher on both situational interest (means: 4.45 vs 3.99, P < .001) and awareness of knowledge gaps (means: 4.13 vs 3.85, P < .01). DISCUSSION: Relative to generating differential diagnoses, reflection upon clinical cases increased learning outcomes on a subsequent study task, an effect that was independent of study time, suggesting that cognitive mechanisms underlie this effect, rather than increases in motivation to study. However, higher scores on situational interest and awareness of knowledge gaps and a tendency towards larger gains when time was free suggest that higher motivation may also contribute to learning from reflection.

'Immunising' physicians against availability bias in diagnostic reasoning: a randomised controlled experiment.

BACKGROUND: Diagnostic errors have often been attributed to biases in physicians' reasoning. Interventions to 'immunise' physicians against bias have focused on improving reasoning processes and have largely failed. OBJECTIVE: To investigate the effect of increasing physicians' relevant knowledge on their susceptibility to availability bias. DESIGN, SETTINGS AND PARTICIPANTS: Three-phase multicentre randomised experiment with second-year internal medicine residents from eight teaching hospitals in Brazil. INTERVENTIONS: Immunisation: Physicians diagnosed one of two sets of vignettes (either diseases associated with chronic diarrhoea or with jaundice) and compared/contrasted alternative diagnoses with feedback. Biasing phase (1 week later): Physicians were biased towards either inflammatory bowel disease or viral hepatitis. Diagnostic performance test: All physicians diagnosed three vignettes resembling inflammatory bowel disease, three resembling hepatitis (however, all with different diagnoses). Physicians who increased their knowledge of either chronic diarrhoea or jaundice 1 week earlier were expected to resist the bias attempt. MAIN OUTCOME MEASUREMENTS: Diagnostic accuracy, measured by test score (range 0-1), computed for subjected-to-bias and not-subjected-to-bias vignettes diagnosed by immunised and not-immunised physicians. RESULTS: Ninety-one residents participated in the experiment. Diagnostic accuracy differed on subjected-to-bias vignettes, with immunised physicians performing better than non-immunised physicians (0.40 vs 0.24; difference in accuracy 0.16 (95% CI 0.05 to 0.27); p=0.004), but not on not-subjected-to-bias vignettes (0.36 vs 0.41; difference -0.05 (95% CI -0.17 to 0.08); p=0.45). Bias only hampered non-immunised physicians, who performed worse on subjected-to-bias than not-subjected-to-bias vignettes (difference -0.17 (95% CI -0.28 to -0.05); p=0.005); immunised physicians' accuracy did not differ (p=0.56). CONCLUSIONS: An intervention directed at increasing knowledge of clinical findings that discriminate between similar-looking diseases decreased physicians' susceptibility to availability bias, reducing diagnostic errors, in a simulated setting. Future research needs to examine the degree to which the intervention benefits other disease clusters and performance in clinical practice. TRIAL REGISTRATION NUMBER: 68745917.1.1001.0068.

Effects of deliberate reflection on students' engagement in learning and learning outcomes.

CONTEXT: Reflection in practice is assumed to enhance interest in knowing more about a topic, increasing engagement in learning and learning outcomes. However, this claim lacks empirical evidence, particularly in medical education. The authors investigated the effects of deliberate reflection upon clinical cases on medical students' engagement in a learning activity and learning outcomes. METHODS: A three-task (diagnostic task; learning activity; test) experiment was conducted in August 2017. Seventy-two fourth-year students from UNIFENAS-BH Medical School, Brazil, diagnosed two clinical cases with jaundice as the chief complaint, either by following a deliberate reflection procedure or making differential diagnosis. Subsequently, all participants received the same study material on the diagnosis of jaundice. Finally, they took a recall test on the study material. Outcome measurements were study time and test scores. RESULTS: There was a significant effect of experimental condition on students' engagement in the learning activity and on learning outcomes. Students who deliberately reflected upon the cases invested more time in studying the material than those who made a differential diagnosis (respectively, mean = 254.97, standard deviation = 115.45 versus mean = 194.96, standard deviation = 111.68; p = 0.02; d = 0.53). Deliberate reflection was also related to higher scores in the test relative to differential diagnosis (respectively, mean = 22.08, standard deviation = 14.94 versus mean = 15.75, standard deviation = 9.24; p = 0.03; d = 0.51). Medium effect sizes (Cohen's d) were observed in both measurements. CONCLUSIONS: Relative to making differential diagnosis, deliberate reflection while diagnosing cases fostered medical students' engagement in learning and increased learning outcomes. Teachers can employ this relatively easy procedure, possibly both with simulated and real scenarios, to motivate their students and help them expand their knowledge, an important requirement for their professional development.

Biomicroscopia ultrassônica na viscocanalostomia / Ultrasound biomicroscopy in viscocanalostomy

OBJETIVO: Estudar por biomicroscopia ultrassônica (UBM) de alta frequência as características anatômicas da viscocanalostomia, e a relação dessas características com a redução da pressão intraocular. MÉTODOS: Estudo transversal, que incluiu nove olhos (sete pacientes) submetidos à viscocanalostomia, e posteriormente examinados por UBM de alta frequência (80 MHz). Os parâmetros da UBM avaliados após um follow-up mínimo de seis meses foram: presença de espaço intraescleral, comprimento e altura máximos do espaço intraescleral, e a espessura mínima da membrana trabéculo-descemética (MTD) residual. O sucesso cirúrgico definiu-se como pressão intraocular (PIO) <22mmHg ou redução de 20% da PIO sem medicação tópica. Possíveis associações entre as variáveis da UBM e o resultado cirúrgico foram avaliados. RESULTADOS: O tempo médio entre a cirurgia e a realização da UBM foi de 15,5 ± 8,8 meses (6 - 29 meses). Verificou-se uma redução da PIO de 23,5 ± 6,9 mmHg (13,7-32,0) pré-operatória para 14,5 ± 2,4 mmHg (10,7-17,3) pós-operatória (p<0,05). Identificou-se a presença de espaço intraescleral em todos os olhos. A média do comprimento máximo do espaço intraescleral era 1,83 ± 0,51mm; a média da altura máxima do espaço intraescleral era 0,36 ± 0,17mm; e a média da espessura mínima da MTD era 0,14 ± 0,07mm. Não foram encontradas correlações significativas entre o valor da PIO pós-operatória e o comprimento do espaço intraescleral (r²=0,359), a altura do espaço intraescleral (r²=0,017) e a espessura da MTD (r²=0,003). CONCLUSÃO: Em pacientes submetidos à viscocanalostomia, a UBM após um follow-up mínimo de seis meses identificou o espaço intraescleral em todos os olhos. Não se encontrou qualquer correlação estatisticamente significativa entre os valores de PIO pós-operatória e as características anatômicas do espaço intraescleral.

PURPOSE: To evaluate by high frequency ultrasound biomicroscopy (UBM) the anatomical characteristics of viscocanalostomy and their relationship with the intraocular pressure (IOP) lowering. METHODS: A transversal study which included 9 eyes (7 patients) undergoing viscocanalostomy and examined by high frequency UBM (80 MHz). Several UBM variables were evaluated, including the presence of the intrascleral space, the maximum length and height of the intrascleral space and the minimum thickness of residual trabeculo-Descemet membrane (TDM). Surgical success was considered to be achieved when IOP was <22mmHg or the IOP was lowered 20% or more without the use of any medication. The possible association between UBM variables and the surgical outcome was determined. RESULTS: The mean time between surgery and the UBM examination was 15.5 ± 8.8 months (range 6-29). The mean IOP decreased from a preoperative value of 23.5 ± 6.9 mmHg (range 13.7-32.0) to 14.5 ± 2.4 mmHg (range 10.7-17.3) postoperative (p<0.05). The presence of an intrascleral space was a constant finding. The mean length of the intrascleral space was 1.83 ± 0.51mm, the mean height was 0,36 ± 0,17mm; and the mean TDM thickness was 0.14 ± 0.07mm. There were a poor correlation between the level of IOP at the time of UBM and the lenght of the intrascleral space (r²=0.359), the height of the intrascleral space (r²=0.017) or the thickness of the remaining TDM (r²=0.003). CONCLUSION: In patients undergoing viscocanalostomy, UBM examination after a minimum of 6-month follow-up period showed the presence of an intrascleral space in all patients. There was no statiscally significant relationship between the level of IOP and the anatomical characteristics of the intrascleral space.

Microsatellite mutations in the offspring of irradiated parents 19 years after the Cesium-137 accident.

In September of 1987, a radiotherapy unit containing 50.9 TBq of Cs(137)Cl was removed from an abandoned radiotherapy clinic. This unit was subsequently disassembled leading to the most serious radiological accident yet to occur in the Western hemisphere. This event provides an opportunity to assess the genetic effects of ionizing radiation. We surveyed genetic variation of 12 microsatellite loci in 10 families of exposed individuals and their offspring and also in non-exposed families from the same area of Goias state. We found an increase in the number of new alleles in the offspring of the exposed individuals. The mutation rate was found to be higher in the exposed families compared to the control group. These results indicated that exposure to ionizing radiation can be detected in offspring of exposed individuals and also suggest that the elevated microsatellite mutation rate can be attributed to radioactive exposure.