Evidence based guidelines

What are Evidence based guidelines?

  • Evidence-based guidelines are collections of statements which recommend how patients with certain conditions should be treated. For example, there is an evidence-based guideline which states that patients with ischaemic stroke should receive 300mg of aspirin within 48 hours.
  • Each of the statements within a guideline are based on evidence. The strength of the evidence supporting each statement will be given. The highest strength of evidence comes from well-conducted systematic reviews and RCTs, and is called ‘Grade A’ evidence (see Additional Information box for more information). For example, there is an evidence based guideline which states that anti-embolism stockings should not be used in stroke patients; this is based on Grade A evidence.
  • Evidence-based guidelines will also contain clear recommendations for future research to fill the gaps in the evidence-base.
  • Evidence-based guidelines may also include suggestions relating to the implementation of the guidelines.
  • Although most patients should be treated in line with the relevant guideline statements, individual factors will determine that some patients should be treated in a different manner.
  • The quality of evidence is described according to a number of different levels (see Additional Information box for further information).