In 1999 a four-level hierarchy of evidence was developed and promoted by the National Health and Medical Research Council (NHMRC) in Australia. Its primary purpose was to assist with clinical practice guideline development, although it has since been co-opted for use in systematic literature reviews and health technology assessments. 

 

In 2009, a working party was convened to review the NHMRC hierarchy with the aim of increasing the relevance of the four-level hierarchy for assessing the quality of individual diagnostic accuracy, prognostic, aetiologic and screening studies.

 

To review the revised NHMRC levels of evidence document please click here.

 

This is also available as a published article by Merlin T, Weston A and Tooher R (2009). Extending an evidence hierarchy to include topics other than treatment: revising the Australian 'levels of evidence'. BMC Medical Research Methodology 9(34).  To view this published article  - click here.  

 

In 2010, this revised level of evidence table was submitted to the international group (see “International datasets underway” story above) and it was agreed to be the tool used to assess levels of evidence in the development of international cancer datasets.