CLINICAL APPLICATION – CLINICAL PREDICTION RULES

A.GOAL

To be able to assess the applicability and validity of published clinical prediction rules and to appropriately apply them to the care of individual patients as well as to the development of clinical policies.

B.CLINICAL SCENARIO

Administrative responsibilities for the “fast-track” ambulatory care unit (FTACU) in your medical center are shared between the departments of Internal Medicine and Emergency Medicine. The unit receives patients from the Emergency Department and outpatient medical services. Practitioners in the FTACU can order STAT tests for patients, including x-rays. However, x-rays require transport of patients to another are of the medical center.

Your attention has been called to a patient complaint involving excessive delay caused by the need to transport for a routine chest x-ray from the FTACU. The patient in question, a 32-year-old male with a history of asthma, presented with a temperature of 100F, a pulse of 95 and a respiratory rate of 20. The physical exam revealed occasional ronchi but no rales and full breath sounds bilaterally. The patient was sent from the ED to the FTACU and then had to make an additional trip for a chest x-ray.

A Nursing coordinator has asked whether the decision to order or not to order a chest x-ray on this and similar patients could be made at Triage. After searching Medline using search terms

‘pneumonia’ as a MeSH and Keyword, and ‘predict’ as a truncated text term. You locate 12 articles, of which one constitutes a clinical decision rule for prediction of pulmonary infiltrates using simple clinical criteria. You decide to present this paper to the next meeting of your division’s practice committee.

C.TEACHING SCENARIO

The Outpatient Practice Committee is made up of physicians and nursing representatives of the Departments of Emergency Medicine and Internal Medicine and is charged with formulating clinical policies and pathways within the outpatient services.

D.ARTICLES

1.) Heckerling PS, Tape TG, Wigtron RS, et al, Clinical Prediction Rule for Pulmonary Infiltrates. Annals Intern Med 1990;113:664-670

2.) McGinn T, Guyatt GH, Wyer PC, Naylor CD, et al, for the Evidence-Based Medicine Working Group: Users’ Guides to the Medical Literature: XXII. How to Use Articles About Clinical Prediction Rules. JAMA . 2000; 284:79-84.

3.) Worksheet for evaluating an article on a clinical prediction rule.

CRITICAL REVIEW FORM FOR A CLINICAL PREDICTION RULE

GUIDE

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COMMENTS

I. Is this a newly derived prediction rule? (Level IV)

1.Were the outcomes and clinical predictors clearly defined and clinically sensible?
2.Were all-important predictors assessed in the derivation of the prediction guide?
3.Was validation restricted to the use of split samples, large retrospective databases, or by various statistical techniques?

II. Has the rule been validated? (Level II or III)

1.Did validation include prospective studies on several different populations from that used to derive it (II), or was it restricted to only one population (III)?
2.Was there appropriate blinding of those assessing the predictors and those assessing the outcome event?

3.What were the sensitivity, specificity, positive and negative predictive values, likelihood rations, relative risks or absolute outcome rates?

4.Was the level of accuracy (NPV, PPV, LR) achieved by the CPG significant enough in light of the severity of the illness being studied?

III. Has an impact analysis demonstrated change in clinical behavior as a result of using the rule? (Level I)