Relative Efficacy of Swallowing versus Non-swallowing Tasks in Dysphagia Rehabilitation: Current Evidence and Future Directions.

Clinical trials published in 2012 and the first six months of 2013 were reviewed. These involved either traditional dysphagia therapy, indirect methods not involving dysphagia therapy or a combination of direct and indirect methods. Of 27 studies, 7 were RCTs, 5 were controlled clinical trials and the remainder were uncontrolled case series. Sixteen studies combined an indirect treatment with traditional dysphagia therapy; only one study examined one technique for direct swallowing therapy. Effect sizes were computed and contrasted for each trial. Traditional dysphagia therapy had small to moderate effect sizes (between 0.3 and 0.6) while spontaneous recovery in acute stroke had effect sizes of 1.2. Placebo effects on patient ratings of degree of improvement on swallowing were estimated as small to moderate. To improve effect sizes, adaptive research designs are needed to develop the optimal methods and dosages of therapy before future clinical trials.