Assessing existing literature
These are vital to decide whether the evidence is strong enough to change clinical practice or as a platform to develop future research projects.
The CASP checklists are useful for critical appraisal of various studies.
Systematic review or meta-analysis
Medical journals now require authors to report their results according to the EQUATOR guidelines which include the CONSORT statement and flow diagram for randomised controlled trials and the PRISMA resources for systematic reviews.
If you are conducting a systematic review or meta-analysis, you can publish your protocol for transparency. You can also look at existing protocols.
Extensive guidance and a useful reference guide on how to conduct a systematic review/meta-analysis has been produced by the Centre for Reviews and Dissemination.
Finding articles is one thing, reading them and deciding whether the evidence is strong enough is quite another. Here are a few resources that might help.
video highlighting key things to consider when undertaking research