Table 3.

The estimated cost of high, uncertain and low risk of bias trials

Risk of bias	Number of trials	Participants	E1 costs (£)	E2 costs (£)	E3 costs (£)
High	1013	222,850	725,599,600	8,004,326,300	2,090,778,700
Uncertain	494	127,290	414,456,240	4,572,002,220	1,194,234,780
Low	133	47,138	153,481,328	1,693,102,684	442,248,716