Confidentiality issues regarding data anonymity and security are similar to those described for IPD meta-analyses in Chapter 18 (Section 18.2.3). Specific issues for PMA include adequate planning regarding how to deal with trials within the PMA that reach completion and will publish their results, and how to manage issues relating to data and safety monitoring, including the impact of interim analyses of individual trials in the PMA, or possibly a pooled interim analysis of the PMA (see also Section 19.5.2).