title: Measuring Change in Symptoms of Neurobehavioural Disability: Responsiveness of the St Andrew's-Swansea Neurobehavioural Outcome Scale.
abstract: OBJECTIVE
  Neurobehavioural disability (NBD) after acquired brain injury (ABI) is often associated with poor outcome. The "St Andrew's-Swansea Neurobehavioural Outcome Scale" (SASNOS) was developed to measure NBD in a range of applications. Two of the "holy trinity" of psychometric properties, reliability and validity, have been comprehensively mapped, but the extent to which SASNOS meets the third, responsiveness, has not been investigated. Demonstrating responsiveness is essential in instruments employed in repeated measurement scenarios to confirm their ability to discriminate real change from error. However, there is no single agreed method for determining responsiveness. For some instruments, this property remains unexplored. A difference in scores attaining statistical significance for aggregate data is frequently cited as support for this construct, but this approach remains heavily criticized. This study explores responsiveness of SASNOS.
  
  
  METHODS
  Consecutive SASNOS assessments completed over varying times for 145 individuals participating in neurobehavioural rehabilitation, drawn from multiple services, were compiled into a retrospective sample of convenience. Multiple methods were employed to confirm internal responsiveness, including those identifying statistically significant change, minimally detectable change and minimally important change.
  
  
  RESULTS
  All methods confirmed responsiveness as a psychometric property of SASNOS; the extent depended on method used and NBD domain investigated. A number of indicators are presented, which equip clinicians and researchers with options to interpret results from repeated assessments, including the individual level in the context of rehabilitation.
  
  
  CONCLUSIONS
  SASNOS reliably measures change over time in NBD symptoms, further confirming its suitability as an instrument for investigating multidimensional outcomes of ABI.
authors.affiliation: Brain Injury Services, Priory Healthcare & Partnerships in Care, Grafton Manor, Grafton Regis, Northants, UK.|Department of Psychology, College of Human and Health Sciences, Swansea University, Swansea, UK.
authors.forename: Nick
authors.initials: N
authors.lastname: Alderman
authors.affiliation: Department of Psychology, College of Human and Health Sciences, Swansea University, Swansea, UK.
authors.forename: Claire
authors.initials: C
authors.lastname: Williams
authors.affiliation: Brain Injury Services, Priory Healthcare & Partnerships in Care, Burton Park, Melton Mowbray, Leicestershire, UK.|School of Psychology, University of Leicester, Leicester, Leicestershire, UK.
authors.forename: Caroline
authors.initials: C
authors.lastname: Knight
authors.affiliation: Neuropsychology Clinic, College of Medicine, Swansea University, Swansea, UK.
authors.forename: Rodger Ll
authors.initials: RL
authors.lastname: Wood
mesh_terms: D000328:Adult; D001526:Behavioral Symptoms / Q000175:diagnosis* / Q000523:psychology; D003072:Cognition Disorders / Q000175:diagnosis*; D005260:Female; D006801:Humans; D007398:Interpersonal Relations; D008297:Male; D001523:Mental Disorders / Q000175:diagnosis* / Q000523:psychology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D017063:Outcome Assessment, Health Care; D011594:Psychometrics; D011795:Surveys and Questionnaires; D006113:United Kingdom
keywords: Assessment; Head injury, traumatic brain injury; Norms/normative studies; Practice effects/reliable change; Rehabilitation; Statistical methods