INTRODUCTION
Applying external trial evidence to the patient sitting in front of you in the clinical setting is perhaps one of the most difficult and least discussed steps of evidence-based medicine.1-2 Having unearthed relevant, high-quality, and valid information from clinical trials in relation to a clinical question generated by a patient encounter, you must answer 5 questions to successfully apply such information to your individual patient.3
1. HOW SIMILAR ARE THE STUDY PARTICIPANTS TO MY PATIENT?
Trial Participants Are Sometimes Atypical
Participants in clinical trials may differ in obvious ways such as age, sex, and clinical disease type from the patient in your office (Table 1).4 In most circumstances, these differences do not prevent you from making some useful generalizations from the literature. For example, I would be quite happy to generalize from a randomized clinical trial (RCT) of topical steroids for atopic eczema that did not use strict diagnostic criteria, provided that the description of the disease . . . [Full Text of this Article]
Groups Are Different From Individuals
Triumph of the Aggregate
Conclusions
2. DO THE OUTCOMES MAKE SENSE TO ME?
Does the Psoriasis Area Severity Index Mean Anything to You?
Sensitive Scales to Amplify Effects
Too Many Scales, and Too Many Short-term Studies
So What Should You Look For?
3. WHAT WAS THE MAGNITUDE OF TREATMENT EFFECTS?
How Big Is Big Enough?
Number Needed to Treat
4. WHAT ARE THE ADVERSE EVENTS?
Trials Are Not a Useful Source of Data on Rare But Serious Adverse Effects
Limitations of Aggregate Data
Communicating Risks
Weighing Risks and Benefits
5. WHAT ARE MY PATIENT'S VALUES?
Values and Belief Models
And If the Treatment Still Does Not Work?
CONCLUSIONS
