Table 1.

Summary of developmental and investigational trials of the PES

Study type	Purpose	Subjects	N
Developmental	Establish optimal parameters for PES	Healthy volunteers	8
Feasibility RCT	Assess short-term effects of PES in altering swallowing after stroke, acute period	Stroke pts with dysphagia	16
Experimental	Assess use of PES to reverse virtual lesions	Healthy volunteers	13
Dose response	Establish the optimal number of treatment sessions based on safety and effectiveness in acute stroke	Stroke pts with dysphagia	22
Phase IIa RCT	Assess safety and effectiveness of optimized PES treatment regimen in acute stroke; 2-week follow-up	Stroke pts with dysphagia	28
Phase IIb RCT	Assess safety and effectiveness of optimized PES treatment regimen in acute stroke; 3-month follow-up	Stroke pts with dysphagia	36
Phase III RCT	Assess PES in acute stroke in a study powered for significance	Stroke pts with dysphagia	133
Phase II RCT	Assess use of PES to facilitate early tracheostomy decannulation	Stroke pts with dysphagia	30
Exploratory	Assess utility of PES in chronic, persistent dysphagia	Stroke pts with dysphagia	6
Feasibility RCT	Assess safety and effectiveness of PES in MS	MS pts with dysphagia	20

Abbreviations: MS, multiple sclerosis; PES, pharyngeal electrical stimulation; pts, patients; RCT, randomized controlled trial.