PPRISMA for reviews including harms outcomes

The PRISMA harms checklist contains four extension items that must be used in any systematic review addressing harms, irrespective of whether harms are analysed alone or in association with benefits. These include:

• Item 1—title: specifically mention “harms” or other related terms, or the harm of interest in the systematic review.
• Item 14—synthesis of results: specify how zero events were handled, if relevant.
• Item 18—study characteristics: define each harm addressed, how it was ascertained (eg, patient report, active search), and over what time period.
• Item 21—synthesis of results: describe any assessment of possible causality.

These items are added to the original PRISMA statement, such that a systematic review addressing adverse events should report the PRISMA statement items and the PRISMA harms.

We also added recommendations for reporting harms in systematic reviews for those items in the original PRISMA checklist that require special consideration when reporting on harms, these items can be seen in the checklist as "recommendations for reporting harms in systematic reviews", they are desirable items to be reported for a more complete information of harms.

Statement paper:

Zorzela Liliane, Loke Yoon K, Ioannidis John P,Golder Su, Santaguida Pasqualina, Altman Douglas G et al. PRISMA harms checklist: improving harms reporting in systematic reviews BMJ 2016; 352:i157 (http://www.bmj.com/content/352/bmj.i157)