Table 2. Question: When can surrogate endpoints be used?

	Stakeholder groups				Medical specialty			Pooled mean
	Regulator	Academia	Industry	P	CR	Other	P
Not enough treatment options	3.5 (1.2)	3.6 (1.2)	4.5 (0.6)	0.012	3.9 (1.1)	3.4 (1.3)	0.24	3.7 (1.2)
Large impact on health and well-being	3.3 (1.4)	3.4 (1.2)	4.6 (0.5)	0.001	3.8 (1.2)	3.2 (1.3)	0.08	3.6 (1.2)
Scientifically validated	4.3 (0.7)	4.3 (1.0)	4.8 (0.4)	0.058	4.4 (0.9)	4.2 (1.0)	0.63	4.3 (1.0)
Hard outcome studies are too costly	2.1 (0.7)	2.1 (1.0)	3.4 (0.9)	<0.001	2.4 (1.1)	2.4 (1.1)	0.86	2.4 (1.1)
Unmet clinical need	3.9 (1.1)	3.4 (1.1)	4.7 (0.6)	<0.001	3.8 (1.2)	3.7 (1.2)	0.96	3.8 (1.2)
Cannot be used without hard outcome studies	2.4 (1.0)	2.9 (1.1)	1.6 (0.6)	<0.001	2.4 (1.1)	2.5 (1.1)	0.55	2.4 (1.1)

Statements on when surrogate endpoints can be used in drug marketing authorization, provided that a post-marketing study with hard outcomes will be conducted. Results from a 5-point Likert response format (strongly disagree – strongly agree) are presented in mean (SD) according to stakeholder group or medical specialty group (cardio-renal vs. no cardio-renal). Statistical differences between groups are mainly driven by differences of industry respondents vs. regulators and academia. Abbreviations: CR, cardiorenal background; P, P value.