4. Separating indirect from direct evidence: duration of mechanical ventilation.

Treatment comparison	Proportion of direct evidence	RoR	P value
Dobutamine versus levosimendan	0.65	2.2276	0.2274
Dobutamine versus milrinone	0.46	0.4489	0.2274
Dobutamine versus placebo, only indirect evidence	0	NA	NA
Levosimendan versus milrinone	0.78	1.7139	0.2276
Levosimendan versus placebo	0.68	0.8550	0.8099
Milrinone versus placebo	0.43	1.1696	0.8099

Separation of indirect from direct evidence using a back‐calculation method, random‐effects model
RoR: ratio of ratios (direct/indirect), with P value of test for disagreement

Abbreviations
NA: not applicable; RoR: ratio of ratios