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Appaisal Checklists

Health Evidence Bulletins - Wales: Questions to assist with the critical appraisal of an observational study eg cohort, cross-sectional, longitudinal, case-control. (Type IV evidence)
Sources used: Critical Appraisal Skills Programme (CASP, Anglia and Oxford RHA) questions and Polgar A, Thomas SA. Chapter 22. Critical evaluation of published research in Introduction to research in the health sciences. 3rd edition. Melbourne: Churchill Livingstone, 1995.

Paper details Authors:

A/ What is this paper about?

  Yes Can't tell No
1. Is the study relevant to the needs of the Project?      
2. Does the paper address a clearly focused issue?
Are the aims of the investigation clearly stated?

B/ Do I trust it?

  Yes Can't tell No
3. Have the authors reflected the current state of knowledge according to an unbiased review of the literature?
  • Has a sufficiently complete search of the relevant literature been carried out?
  • Is evidence included which is unfavourable to the authors’ point of view?
4. Is the choice of study method appropriate?      
5. Is the population studied appropriate?
Is an appropriate control group used?
6. Is confounding and bias considered?
  • Have all possible explanations of the effects been considered?
  • Were the assessors blind to the different groups?
  • Could selective drop out explain the effect?
7. Was Follow up for long enough?
  • Could all likely effects have appeared in the time scale?
  • Could the effect be transitory?
  • Was follow up sufficiently complete?
8. Was Dose Response demonstrated?      


C/ What did they find?

  Yes Can't tell No
9. Are tables/graphs adequately labelled and understandable?      
10. Are you confident with the authors' choice and use of statistical methods, if employed?      
11. What are the results of this piece of research?
Are the authors' conclusions adequately supported by the information cited?

D/ Are the results relevant locally?

  Yes Can't tell No
12. Can the results be applied to the local situation?
Consider differences between the local and study populations (eg cultural, geographical, ethical) which could affect the relevance of the study.
13. Were all important outcomes/results considered?      
14. Accept for further use as Type IV evidence?   Refer to Team Leader  


Draft Statement (if appropriate):
(Remember to include the relevant target group (age range, sex etc.); the measured outcomes/benefits with quantitative information if available; and the health gain notation)