Tips for Teachers of Evidence-based Medicine: Clinical Prediction Rules (CPRs) and Estimating Pretest Probability

Abstract

Background Clinical prediction rules (CPR) are tools that clinicians can use to predict the most likely diagnosis, prognosis, or response to treatment in a patient based on individual characteristics. CPRs attempt to standardize, simplify, and increase the accuracy of clinicians’ diagnostic and prognostic assessments. The teaching tips series is designed to give teachers advice and materials they can use to attain specific educational objectives. Educational Objectives In this article, we present 3 teaching tips aimed at helping clinical learners use clinical prediction rules and to more accurately assess pretest probability in every day practice. The first tip is designed to demonstrate variability in physician estimation of pretest probability. The second tip demonstrates how the estimate of pretest probability influences the interpretation of diagnostic tests and patient management. The third tip exposes learners to various examples and different types of Clinical Prediction Rules (CPR) and how to apply them in practice. Pilot Testing We field tested all 3 tips with 16 learners, a mix of interns and senior residents. Teacher preparatory time was approximately 2 hours. The field test utilized a board and a data projector; 3 handouts were prepared. The tips were felt to be clear and the educational objectives reached. Potential teaching pitfalls were identified. Conclusion Teaching with these tips will help physicians appreciate the importance of applying evidence to their every day decisions. In 2 or 3 short teaching sessions, clinicians can also become familiar with the use of CPRs in applying evidence consistently in everyday practice.

Diagnostic accuracy systematic review of rectal bleeding in combination with other symptoms, signs and tests in relation to colorectal cancer

“…Future studies should recruit consecutive patients, apply an agreed reference standard to all patients and evaluate the combined value of symptoms, signs and diagnostic tests in the form of a clinical prediction rule (McGinn et al, 2008). Future primary studies should also report their data completely, preferably using the Standards for Reporting of Diagnostic Accuracy (STARD) criteria as guidelines (Bossuyt et al, 2003).…”

Predicting Risk of Urinary Incontinence and Adverse Events After Midurethral Sling Surgery in Women

“…2 Moreover, there have been recent proposals that predictive tools should become part of essential recommendations for clinical care and included into guideline recommendations. [3][4][5][6] Despite their increased use in many areas involving nonsurgical decisions, the availability of predictive analytic tools and their use during the surgical consent process are less well characterized.…”

“…Because there is large variability in the predicted rates given to patients and clinical prediction models show consistent superiority over expert clinicians as a result of physician cognitive biases, we assume that there is added value in using prediction models to provide more accurate estimates of risk to patients. [3][4][5] …”

Prediction scores in gastrointestinal bleeding: a systematic review and quantitative appraisal

“…A fair part was extracted from the publications by Laupacis et al and Wasson et al [8,25], in which several methodological standards were described. Additionally, standards identified in studies by McGinn et al [7,24] were included. All of these standards originate from guidelines, but as no validated instruments are available these are often used to assess the quality of prediction rules [48].…”

“…Quality appraisal was performed by using methodological standards as published previously [7,8,24,25]. The assessment items are shown in • " Table 1 B.)…”