Critical Appraisal Skills Programme (CASP) part of Better Value Healthcare Ltd www.casp-uk.net
CASP Checklist: 11 questions to help you make sense of a Randomised Controlled Trial
How to use this appraisal tool: Three broad issues need to be considered when appraising a trial:
Are the results of the study valid? (Section A)
What are the results? (Section B)
Will the results help locally? (Section C) The 11 questions on the following pages are designed to help you think about these issues systematically. The first three questions are screening questions and can be answered quickly. If the answer to both is “yes”, it is worth proceeding with the remaining questions. There is some degree of overlap between the questions, you are asked to record a “yes”, “no” or “can’t tell” to most of the questions. A number of italicised prompts are given after each question. These are designed to remind you why the question is important. Record your reasons for your answers in the spaces provided.
About: These checklists were designed to be used as educational pedagogic tools, as part of a workshop setting, therefore we do not suggest a scoring system. The core CASP checklists (randomised controlled trial & systematic review) were based on JAMA 'Users’ guides to the medical literature 1994 (adapted from Guyatt GH, Sackett DL, and Cook DJ), and piloted with health care practitioners.
For each new checklist, a group of experts were assembled to develop and pilot the checklist and the workshop format with which it would be used. Over the years overall adjustments have been made to the format, but a recent survey of checklist users reiterated that the basic format continues to be useful and appropriate.
Referencing: we recommend using the Harvard style citation, i.e.: Critical Appraisal Skills Programme (2018). CASP (insert name of checklist i.e. Randomised Controlled Trial) Checklist. [online] Available at: URL. Accessed: Date Accessed.
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Section A: Are the results of the trial valid?
1. Did the trial address a clearly
focused issue?
Yes HINT: An issue can be ‘focused’ In terms of • the population studied • the intervention given • the comparator given
• the outcomes considered
Can’t Tell
No
Comments:
2. Was the assignment of patients to treatments randomised?
Yes HINT: Consider
• how this was carried out
• was the allocation sequence concealed
from researchers and patients
Can’t Tell
No
Comments:
3. Were all of the patients who entered the trial properly accounted for at its conclusion?
Yes
HINT: Consider
• was the trial stopped early
• were patients analysed in the groups to which they were randomised
Can’t Tell
No
Comments: