PE Calc The PE Calc app is a calculator based on the Wells’ Criteria prediction rules. The well-validated clinical prediction rule can be applied on the spot to help predict the pretest probability of pulmonary embolism (PE). When history and physical reveal suspicion of a PE, the PE Calc app can be used to identify patients for whom VTE (venous thromboembolism) is a diagnostic possibility. At risk patients should undergo further testing. Description To use PE Calc, enter a yes or no resp