If prepared as a Cochrane review, the PMA protocol should be submitted to the appropriate Cochrane Review Group to appear in the Cochrane Database of Systematic Reviews. Otherwise, a protocol should be published elsewhere (for example, the CTT/PPP Protocol (Cholesterol Treatment Trialists' (CTT) Collaborators 2005)). It is also desirable that PMA projects are registered on the Cochrane Prospective Meta-analysis Methods Group web site (see Box 19.6.a) and information about the project should be updated at least annually. Each trial within the PMA should be registered on a publicly accessible, WHO recognized, Primary Registry (www.who.int/ictrp/network/list_registers) prior to enrolment of the first participant, in accordance with international requirements (Sim 2006, Laine 2007).