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Centre for Evidence-
Based Medicine

Therapy Critical Appraisal Worksheet

Download this worksheet [Word document; 23kb]

Are the results of this single preventive or therapeutic trial valid?

Are the valid results of this randomised trial important?

Sample calculations

show/hide sample calculations

Your Calculations

Occurrence of diabetic neuropathy at 5 years among insulin-dependent diabetics in the DCCT trial Relative risk reduction
Absolute risk reduction
Number needed to treat
95% CI*=>

Can you apply this valid, important evidence about therapy in caring for your patient?

Do these results apply to your patient?

What are your patient's potential benefits and harms from the therapy?

  1. Method I: f
    Risk of the outcome in your patient, relative to patients in the trial. :

    / = / =
    (NNT for patients like yours)
  2. Method II: 1/(PEER x RRR)

    1/ = 1 / =
    (NNT for patients like yours)

Are your patient's values and preferences satisfied by the regimen and its consequences?