title: A randomized clinical trial of negative pressure ventilation in severe chronic obstructive pulmonary disease: design and methods.
abstract: This report documents the design and methods of a randomized clinical trial designed to test the effectiveness of home negative pressure ventilation in patients with severe chronic obstructive pulmonary disease. Active negative pressure ventilation was compared with a sham version of the treatment after a pre-trial assessment had indicated the feasibility of the latter. Over 1200 patients in the metropolitan Montreal area were screened. Of these, 348 patients were recruited to enter a 4-week stabilization period, and 184 were subsequently randomized to receive either active or sham negative pressure ventilation. A 5-day in-hospital period was used to train patients in ventilator use and obtain baseline measures of exercise capacity, lung function, respiratory symptoms, and quality of life. Home ventilation treatment took place during a following 12-week period. Respirator use was recorded both from patient logs and from concealed meters installed in the units. Patients received four home visits by physiotherapists during the 12-week period and returned for follow-up to the hospital 4 and 12 weeks post-discharge for reassessment.
authors.affiliation: Department of Epidemiology and Biostatistics, McGill University, Montreal, Quebec, Canada.
authors.forename: S H
authors.initials: SH
authors.lastname: Shapiro
authors.forename: P T
authors.initials: PT
authors.lastname: Macklem
authors.forename: K
authors.initials: K
authors.lastname: Gray-Donald
authors.forename: J G
authors.initials: JG
authors.lastname: Martin
authors.forename: P P
authors.initials: PP
authors.lastname: Ernst
authors.forename: S
authors.initials: S
authors.lastname: Wood-Dauphinee
authors.forename: T A
authors.initials: TA
authors.lastname: Hutchinson
authors.forename: W O
authors.initials: WO
authors.lastname: Spitzer
mesh_terms: D000368:Aged; D000886:Anthropometry; D005080:Exercise Test; D005240:Feasibility Studies; D005260:Female; D006699:Home Care Services; D006801:Humans; D008173:Lung Diseases, Obstructive / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D010349:Patient Compliance; D011788:Quality of Life; D015919:Ventilators, Negative-Pressure