Six RCTs were included in the review (2,023 patients, range 10 to 1,659) with treatment arms for norepinephrine (995 patients) or dopamine (1,028 patients). All six of the trials assessed incomplete outcome data, five were free of selective outcome reporting and four reported adequate sequence generation. Other results were more varied (reported in paper).
The risk of in-hospital or 28-day mortality was 9% lower with norepinephrine than with dopamine (RR 0.91, 95% CI 0.83 to 0.99; Ι²=0%; six trials); results for the fixed-effect and random-effects models were identical. A similar but statistically non-significant result was found when a study with a mixed population of shock patients was excluded (RR 0.84, 95% CI 0.68 to 1.02; Ι²=0%; five trials).
There was no evidence of small-study effects. Secondary outcomes were reported.