Study	Reason for exclusion
Davis 1992	This was a double‐blinded, placebo‐controlled, cross‐over trial that was done on a single participant, with the outcomes measured while the participant was alternating on or off 3,4‐diaminopyridine versus placebo, with no evident attempt to randomize when the participant received the intervention.
Kaplan 1979	This was a double‐blinded, placebo‐controlled, cross‐over trial where 50% of the participants (3 of 6 participants) withdrew from the study before receiving placebo, and there was no attempt to randomly assign participants to intervention versus placebo.