After the launch of the Cochrane Handbook for Systematic Reviews of Interventions in July 2019 we are now announcing the first update to the online version.

In this update there are two changes. The first change is a  clarification in Chapter 14, Section 2.2, relating to certainty of evidence and reasons for downgrading, and the second is a change to the authorship of Chapter 20:

• The first sentence of the Section 14.2.2 Domains that can lead to decreasing the certainty level of a body of evidence reads:  We now describe in more detail the five reasons (or domains) for downgrading the certainty of a body of evidence for a specific outcome. In each case, if no reason is found for downgrading the evidence, it should be classified as ‘no limitation or not serious’ (not important enough to warrant downgrading). If a reason is found for downgrading the evidence, it should be classified as ‘serious’ (downgrading the certainty rating by one level) or ‘very serious’ (downgrading the certainty grade by two levels). For non-randomized studies assessed with ROBINS-I, rating down by three levels should be classified as ‘extremely’ serious.

• Patricia Aluko is now the first and corresponding author for Chapter 20 on economic evidence, and Ian Shemilt has stepped down as co-author. This change is reflected in the new authorship list and citation of the Chapter.  

See the Handbook versions and changes page for more details.

With the versioning update, the correct citation of the updated online Handbook is: 

Higgins JPT, Thomas J, Chandler J, Cumpston M, Li T, Page MJ, Welch VA (editors). Cochrane Handbook for Systematic Reviews of Interventions version 6.1 (updated September 2020). Cochrane, 2020.

All individual chapters have an updated citation as well, at the start of each chapter.

The citation for the print edition of the Handbook remains unchanged:

Higgins JPT, Thomas J, Chandler J, Cumpston M, Li T, Page MJ, Welch VA (editors). Cochrane Handbook for Systematic Reviews of Interventions. 2nd Edition. Chichester (UK): John Wiley & Sons, 2019

Going forward, we expect to update the online Handbook once every year in August to reflect any changes or adjustments. For details on the process for updating the Handbook, please see here.

If you have any questions, please contact methods@cochrane.org.