Methodology in core outcome set (COS) development: the impact of patient interviews and using a 5-point versus a 9-point Delphi rating scale on core outcome selection in a COS development study

Table 5 details attrition rates for per stakeholder group

	*5-Point Survey*			*9-Point Survey*
Stakeholder Group	R1-R2	R2-R3	Overall	R1-R2	R2-R3	Overall
Clinician	30%	10%	37%	40%	14%	48%
Clinician/Researcher	17%	0%	17%	7%	0%	7%
Patient	30%	29%	50%	45%	33%	64%
Researcher	0%	0%	0%	15%	0%	15%
Service Provider/Policy Makers	40%	0%	40%	17%	0%	17%
Overall	25%	9%	32%	32%	11%	39%

ISSN: 1471-2288