Download the CASP critical appraisal checklists for:
- CASP Randomised Controlled Trial Checklist
- CASP Systematic Review Checklist
- CASP Cohort Study Checklist
- CASP Case Control Study Checklist
- CASP Qualitative Research Checklist
- CASP Economic Evaluations Checklist
- CASP Diagnostic Test Checklist
- CASP Clinical Prediction Rule Checklist
Everyone is interested in having good health and there is worldwide interest in making health care more effective…..however:
- How do we know which treatments or interventions really work?
- How can you tell whether a piece of research has been done properly and that the information it reports is reliable and trustworthy?
- How can health care commissioners know which treatments or services are truly worth funding?
- How can patients decide whether the benefits of a particular intervention are likely to outweigh the harms and costs?
- How can you decide what to believe when making a health care decision, when research on the same topic comes to different conclusions?
There are numerous examples that show that doing things, or advising people to do things, just because they seem like a good idea at the time has frequently resulted in more harm than good. If we are going to make sensible choices about treatments and interventions we need to ensure that we are informed by the best available research evidence. This is where critical appraisal skills help.
Critical Appraisal Skills
Critical Appraisal Skills enable you to assess the trustworthiness, relevance and results of published papers so that you can decide if they are believable and useful.
We evaluate scientific articles in three steps:
- Is the study valid?
The first step is to decide whether the study was unbiased by evaluating its methodological quality. Different criteria for validity of articles are used for different types of question: questions on treatment, diagnosis, prognosis and economic evaluation. Depending on the validity of an article we can classify it within a scale of levels of evidence and degrees of recommendation.
- What are the results?
If we decide that the study is valid, we can go on to looking at the results. At this step we consider whether the study’s results are clinically important. For example, did the experimental group show a significantly better outcome compared with the control group? We also consider how much uncertainty there is about the results, as expressed in the form of p values, confidence intervals and sensitivity analysis.
- Are the results applicable to my needs?
Once you have decided that your evidence is valid and important, you need to think about how it applies to your clinical question. It’s likely, for example, that your patient or population may have different characteristics to those in the study. CASP provides a framework within which to consider these issues in an explicit, transparent way.