Noguchi Yoshinori, Matsui Kunihiko, Imura Hiroshi, Kiyota Masatomo, Fukui Tuguya
Kyoto University Graduate School of Medicine, Kyoto, Japan.
J Gen Intern Med. 2002 Nov;17(11):839-44. doi: 10.1046/j.1525-1497.2002.20139.x.
To explore the diagnostic thinking process of medical students.
Two hundred twenty-four medical students were presented with 3 clinical scenarios corresponding to high, low, and intermediate pre-test probability of coronary artery disease. Estimates of test characteristics of the exercise stress test, and pre-test and post-test probability for each scenario were elicited from the students (intuitive estimates) and from the literature (reference estimates). Post-test probabilities were calculated using Bayes' theorem based upon the intuitive estimates (Bayesian estimates of post-test probability) and upon the reference estimates (reference estimates of post-test probability). The differences between the reference estimates and the intuitive estimates, and between Bayesian estimates and the intuitive estimates were used for assessing knowledge of test characteristics, and ability of estimating pre-test and post-test probability of disease.
Medical students could not rule out disease in low or intermediate pre-test probability settings, mainly because of poor pre-test estimates of disease probability. They were also easily confused by test results that differed from their anticipated results, probably because of their inaptitude in applying Bayes' theorem to real clinical situations. These diagnostic thinking patterns account for medical students or novice physicians repeating unnecessary examinations.
Medical students' diagnostic ability may be enhanced by the following educational strategies: 1) emphasizing the importance of ruling out disease in clinical practice, 2) training in the estimation of pre-test disease probability based upon history and physical examination, and 3) incorporation of the Bayesian probabilistic thinking and its application to real clinical situations.
探讨医学生的诊断思维过程。
向224名医学生展示了3个临床病例，分别对应冠状动脉疾病的高、低和中等预检概率。从学生（直观估计）和文献（参考估计）中得出运动负荷试验的检验特征估计值，以及每个病例的预检和后检概率。后检概率是根据直观估计（后检概率的贝叶斯估计）和参考估计（后检概率的参考估计）使用贝叶斯定理计算得出的。参考估计与直观估计之间以及贝叶斯估计与直观估计之间的差异用于评估对检验特征的了解以及估计疾病预检和后检概率的能力。
医学生在低或中等预检概率情况下无法排除疾病，主要原因是对疾病概率的预检估计不佳。他们也容易被与预期结果不同的检验结果所迷惑，这可能是因为他们不善于将贝叶斯定理应用于实际临床情况。这些诊断思维模式导致医学生或新手医生重复进行不必要的检查。
可通过以下教育策略提高医学生的诊断能力：1）强调在临床实践中排除疾病的重要性；2）基于病史和体格检查进行疾病预检概率估计的培训；3）纳入贝叶斯概率思维及其在实际临床情况中的应用。
