Ahn E, Choi G, Kang H, Baek C, Jung Y, Woo Y, Bang S. PLoS One. 2018 Nov 5;13(11):e0206804
This network meta-analysis (with a mixed-treatment comparison method to combine direct and indirect comparisons) compared the effectiveness of seven different SADs as a strategy for unassisted tracheal intubation. The primary outcome was the overall success rate of intubation by intention to treat (ITT) and the secondary outcomes included the overall tracheal intubation success rate (per protocol - PP) and the success rate of tracheal intubation at first attempt by ITT and PP.
Link to abstract.