Efeito da autoexplicação dos mecanismos fisiopatológicos das doenças, na competência diagnóstica em estudantes de Medicina

Abstract

The mechanisms involved on self-explanation and diagnostic skills of medical students have been studied in the last decade. Few of them used the pathophysiological mechanisms of diseases as a guide for instructional approach of self-explanation. The purpose of this study was to investigate the effect of self-explanation strategy oriented to use of pathophysiology on medical students diagnostic accuracy during resolution of clinical cases. METHODS: This was an experimental study with a training phase and an assessment phase, conducted with 39 fourth year medical students, randomly assigned to one of two groups. In the training phase, the experimental group (n = 20) solved eight clinical cases (three cases of jaundice, three cases of chest pain and two filler cases) performing self-explanations about the pathophysiological mechanisms and the control group (n = 19) solved the same set of cases, but without specific guidance for resolution. After one week, in assessment phase, students of both groups were invited to solve, without any specific orientation, a new set of 10 different clinical cases, six with the same diagnosis from the training phase, but with more complexity, two with a different diagnosis but with similar clinical manifestations from de training phase (jaundice and chest pain) and two new filler cases. The diagnostic accuracy was assessed in both phases. RESULTS: Repeated-measures analysis of variance on the mean diagnostic accuracy scores (range:0-1) showed no significant difference between performance moment and experimental condition (F (2;74) = 0,879; p=0,419) or between groups (F(1;37) = 2,871; p=0,099). Post hoc analysis found a significant interaction (F(2;74) = 4,485; p=0,022) between students performance diagnostic accuracy moment and clinical syndrome type, with scores for cases related with jaundice syndrome improving from the first to the last phase in both groups. The same did not occur for cases involving chest pain syndrome. When comparing groups and their performances by type of clinical syndromes we noted that self-explanation group had higher gains in their accuracy scores for jaundice, (p=0,035) compared to the control group. CONCLUSIONS: Self-explanation focusing on the causal mechanisms of the clinical findings present in a case did not improve students diagnostic competence. However, it seems favor diagnostic accuracy of students for clinical syndromes that share not only clinical manifestations, but share pathophysiological mechanism such has happened for jaundice clinical syndromes.