title: Dose response of task-specific upper limb training in people at least 6 months poststroke: A phase II, single-blind, randomized, controlled trial.
abstract: OBJECTIVE
  The objectives of this work were to (1) determine whether higher doses of motor therapy in chronic poststroke hemiparesis result in better outcomes, compared to lower doses, and (2) evaluate potential modifiers of the dose-response relationship.
  
  
  METHODS
  Eighty-five adults with upper extremity paresis ≥6 months poststroke were randomized to one of four dose groups in this single-blind, parallel, randomized, control trial. The dosing parameter manipulated was amount of task-specific training, as indexed by the number of task repetitions. Groups received 3,200, 6,400, 9,600, or individualized maximum (IM) repetitions, during 1-hour sessions, 4 days/week for 8 weeks. The intervention was an individualized, progressive, task-specific upper-limb training program designed to improve upper-limb functional motor capacity. The primary outcome was the slope of the Action Research Arm Test (ARAT) during the intervention. Effects of dose and potential modifiers of the dose-response relationship were evaluated with hierarchical linear models.
  
  
  RESULTS
  ARAT scores for the 3,200, 9,600, and IM groups improved over time as indicated by slopes (ΔARAT/week, mean ± standard errors) of 0.40 ± 0.15, 0.31 ± 0.16, and 0.66 ± 0.14, respectively (p < 0.05). The slope of the 6,400 group was smaller (-0.05 ± 0.15) and significantly different from the 3,200 and IM groups (p < 0.001). Initial motor capacity, neglect, and other tested characteristics did not modify the dose-response relationship.
  
  
  CONCLUSIONS
  Overall, treatment effects were small. There was no evidence of a dose-response effect of task-specific training on functional capacity in people with long-standing upper-limb paresis poststroke. Ann Neurol 2016;80:342-354.
authors.affiliation: Program in Physical Therapy, Washington University School of Medicine, St. Louis, MO. langc@wustl.edu.|Program in Occupational Therapy, Washington University School of Medicine, St. Louis, MO. langc@wustl.edu.|Department of Neurology, Washington University School of Medicine, St. Louis, MO. langc@wustl.edu.
authors.forename: Catherine E
authors.initials: CE
authors.lastname: Lang
authors.affiliation: Department of Psychological and Brain Sciences, Washington University, St. Louis, MO.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Strube
authors.affiliation: Program in Physical Therapy, Washington University School of Medicine, St. Louis, MO.|Program in Occupational Therapy, Washington University School of Medicine, St. Louis, MO.|Department of Neurology, Washington University School of Medicine, St. Louis, MO.
authors.forename: Marghuretta D
authors.initials: MD
authors.lastname: Bland
authors.affiliation: Program in Physical Therapy, Washington University School of Medicine, St. Louis, MO.
authors.forename: Kimberly J
authors.initials: KJ
authors.lastname: Waddell
authors.affiliation: Program in Physical Therapy, Washington University School of Medicine, St. Louis, MO.
authors.forename: Kendra M
authors.initials: KM
authors.lastname: Cherry-Allen
authors.affiliation: Department of Rehabilitation Medicine, Kansas University Medical Center, Kansas City, KS.
authors.forename: Randolph J
authors.initials: RJ
authors.lastname: Nudo
authors.affiliation: Department of Rehabilitation Medicine, Georgetown University and MedStar National Rehabilitation Hospital, Washington, DC.
authors.forename: Alexander W
authors.initials: AW
authors.lastname: Dromerick
authors.affiliation: Program in Physical Therapy, Washington University School of Medicine, St. Louis, MO.|Program in Occupational Therapy, Washington University School of Medicine, St. Louis, MO.|Department of Neurology, Washington University School of Medicine, St. Louis, MO.
authors.forename: Rebecca L
authors.initials: RL
authors.lastname: Birkenmeier
mesh_terms: D000368:Aged; D005081:Exercise Therapy / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010043:Outcome and Process Assessment, Health Care; D010291:Paresis / Q000209:etiology / Q000534:rehabilitation*; D016037:Single-Blind Method; D020521:Stroke / Q000150:complications / Q000628:therapy*; D000071939:Stroke Rehabilitation / Q000379:methods*; D013997:Time Factors; D034941:Upper Extremity / Q000503:physiopathology*