The ‘Characteristics of studies awaiting classification’ table (formerly ‘Studies awaiting assessment’) has the same structure as the ‘Characteristics of included studies’ table. It should be used for two categories of study:
Studies about which an inclusion or exclusion decision cannot be made because sufficient information is not currently available. All reasonable attempts to obtain information must be made before studies are left here on publication of the review, but the review should not be delayed excessively waiting for this information, especially if the inclusion or exclusion of the study is unlikely to have an impact on the review's conclusions. When information is not available for a table entry, the text ‘Not known’ should be inserted.
Studies that have been identified but are awaiting an update to the review. In particular, it is appropriate to mention studies that have the potential to impact on the review’s conclusions, or studies that receive wide publicity, in the review in the period between updates. An amended review may therefore be produced with such studies summarized in this table. The full update, with such studies fully incorporated, should be completed as soon as possible. When information is not available for a table entry, the text ‘Not yet assessed’ or ‘Not known’ should be inserted, as appropriate.