DO PHYSICIANS CORRECTLY ESTIMATE THE IMPORTANCE OF CLINICAL FINDINGS? THE CASE OF ASCITES

It is critical to understand how accurately physicians can estimate the importance of each clinical finding in estimating the probability of a specific diagnosis in the process of clinical decision making. This study aimed to investigate whether physicians’ estimates of the importance of various clinical findings of ascites correlated with the positive likelihood ratios of these findings in diagnosis of ascites.
One hundred and ten physicians were asked to respond to a questionnaire. In this questionnaire they were presented with a clinical scenario about a patient suspected of having ascites followed by a list of clinical findings. Participants were asked to assign a weight (between 0 and 100%) to each clinical finding based on their perception of how much the presence of that finding changed the probability of ascites for the patient. Positive likelihood ratios of those findings were extracted from current best evidence. We investigated if the weights assigned by physicians were associated with the positive likelihood ratios of those findings.
Significant differences were discovered between the weights assigned by the physicians and the positive likelihood ratios for each clinical finding. Significant positive correlation was observed between the weights assigned by different groups of physicians.
Physicians inaccurately estimated the importance of various clinical findings in the diagnosis of ascites. Further research is needed to determine if such inaccurate estimations would lead to any adverse clinical outcomes