Evidence Based Practice Module, therapy and harm

1. Access the so calledEBP calculator for calculating post-test probability. Choose any three sets of figures for sensitivity, specificity and pre-test probability. Either calculate the post-test probability with your own calculator or use the nomogram, and compare with the results using this EBP calculator. Note down the sets of values for which this EBP calculator give the correct answers, and the sets of values which this EBP calculator gives incorrect answers. Make a note of your working, and bring it to the session on 17 October.

Randomised controlled trials

1. Read the following article on the validity of a randomised controlled trial. You should find you know quite a bit about it from your M201 or M101 course. Please read it as a revision, as I will be skim through it rather quickly in the session.

Guyatt GH, Sackett DL, Cook DJ. Users' Guides to the Medical Literature. How to use an article about therapy or prevention
A. Are the results study valid? JAMA 1993 270(21): 2598-2601 and

2. Read through the following article about applying an RCT to your patient. Don't worry if you don't understand everything in this paper. We will be covering mainly this material in the session:-

Guyatt GH, Sackett DL, Cook DJ. Users' Guides to the Medical Literature. How to use an article about therapy or prevention B. What were the results and will they help me in caring for my patients? JAMA 1994, 271(1) 59-63.

3. Read the first 6 paragraphs here to familiarise yourself with the concepts of:-

Randomisation
Blinding (single / double)
Intention to treat analysis

If you are not confident about the following terms:-

Experimental event rate
Control event rate
Relative risk reduction
Aboslute risk reduction
Numbers needed to treat

make use of the Glossary of EBP terms to help you if necessary.

Again, we will cover these during the session.

4. Prepare as far as you can for the case scenario. You can download the case scenario and appraisal tool here. (N.B. Password protected for current students only, you were given a paper copy in the last session)

In order to prepare this scenario, you need to read the following RCT. A paper copy of was also given to you in the last session.

Fagevik Olsen M. et al. Randomised controlled trial of prophylactic chest physiotherapy in major abdominal surgery. British Journal of Surgery, 1997, 84: 1535-1538.

5. When you are confident about the material above, try these two self-assessment tests. Don't worry if you are not sure about every questions, just have a go.

MCQ3a - Introduction to RCT
MCQ3b - RCT(2)

Skills in using information technology

1. Practise the searching skills we have covered in the last session. Have a look through the new "table of contents" facility and the "Miscellaneous" section in the search page.

This page is created and maintained by Wai-Ching Leung
e-mail:- w-c.leung@uea.ac.uk
last modified October 2001

Evidence-Based Practice ModuleFrom:- Wai-Ching Leung and colleagues wp102@yahoo.comTherapy and harm (1)

Evidence-Based Practice Module
From:- Wai-Ching Leung and colleagues wp102@yahoo.com
Therapy and harm (1)