Recent developments in diagnosis and intervention for aspiration and dysphagia in stroke and other neuromuscular disorders.

This review discusses the impact of the evidence-based report on dysphagia diagnosis and treatment in stroke patients prepared in 1999 by ECRI under contract with the Agency for Healthcare Research and Quality (AHRQ). Subsequent research findings are highlighted and research design and reporting problems in the field are discussed. Progress has been made toward standardizing training and rating of videofluoroscopic studies of swallowing (VFSS); however, a consensus does not yet exist. A randomized, controlled trial demonstrated that treatment directed by fiber-optic endoscopic evaluation of swallowing with sensory testing (FEESST) or VFSS resulted in approximately equivalent pneumonia rates. These two different methods provide both overlapping and complementary information. There is discussion of the research design problems of mixed patients versus homogeneous populations, case-control diagnostic studies, inappropriate calculations of diagnostic sensitivity/specificity using imperfect "gold standards," the lack of concurrent control groups in treatment studies, and the misuse of statistical significance tests and P values in examining matching of patient characteristics in comparative studies and in identifying important variables in regression analysis.