Table 2.

20 issues emerging from breakout groups requiring clarification and resolution before the Core Area model could be fully accepted.

Death	Death may not be an outcome of interest.
	Should states worse than death be mentioned?
Life Impact	Should Life Impact be subdivided further?
Resource Use	What does this mean?
	Are there any surrogates?
	What point of view is considered (patient, health system, society)?
	Will measurement of resource use be impractical in many trials?
Pathophysiological Manifestations	Can clinical signs (and sometimes symptoms) also indicate pathophysiological status?
	Need to be flexible about how this is defined.
Contextual Factors	Can we better define what these factors are?
	Can we provide a list?
	Can we better distinguish between factors?
	Who decides what is required?
Some general issues	Can we provide more concrete examples?
	Are adverse effects a core area in themselves?
	Difference between domains and instruments unclear.
	Will instruments crossing domains be a problem?
Some process issues	Difference between core areas and primary and secondary outcomes.
	Does core set development come to a stop if one or more Core Domains does not have a validated instrument?
	There should be provision for updating or revision of Core Outcome sets as further data accumulate.