title: Sensitivity to change and responsiveness of four balance measures for community-dwelling older adults.
abstract: BACKGROUND
  Impaired balance has a significant negative impact on mobility, functional independence, and fall risk in older adults. Although several, well-respected balance measures are currently in use, there is limited evidence regarding the most appropriate measure to assess change in community-dwelling older adults.
  
  
  OBJECTIVE
  The aim of this study was to compare floor and ceiling effects, sensitivity to change, and responsiveness across the following balance measures in community-dwelling elderly people with functional limitations: Berg Balance Scale (BBS), Performance-Oriented Mobility Assessment total scale (POMA-T), POMA balance subscale (POMA-B), and Dynamic Gait Index (DGI).
  
  
  METHODS
  Retrospective data from a 16-week exercise trial were used. Secondary analyses were conducted on the total sample and by subgroups of baseline functional limitation or baseline balance scores.
  
  
  METHODS
  Participants were 111 community-dwelling older adults 65 years of age or older, with functional limitations. Sensitivity to change was assessed using effect size, standardized response mean, and paired t tests. Responsiveness was assessed using minimally important difference (MID) estimates.
  
  
  RESULTS
  No floor effects were noted. Ceiling effects were observed on all measures, including in people with moderate to severe functional limitations. The POMA-T, POMA-B, and DGI showed significantly larger ceiling effects compared with the BBS. All measures had low sensitivity to change in total sample analyses. Subgroup analyses revealed significantly better sensitivity to change in people with lower compared with higher baseline balance scores. Although both the total sample and lower baseline balance subgroups showed statistically significant improvement from baseline to 16 weeks on all measures, only the lower balance subgroup showed change scores that consistently exceeded corresponding MID estimates.
  
  
  CONCLUSIONS
  This study was limited to comparing 4 measures of balance, and anchor-based methods for assessing MID could not be reported.
  
  
  CONCLUSIONS
  Important limitations, including ceiling effects and relatively low sensitivity to change and responsiveness, were noted across all balance measures, highlighting their limited utility across the full spectrum of the community-dwelling elderly population. New, more challenging measures are needed for better discrimination of balance ability in community-dwelling elderly people at higher functional levels.
authors: Health and Disability Research Institute, Boston University School of Public Health, Boston University, Boston, MA 02118-2526, USA. poonamp@bu.edu
authors: Poonam K
authors: PK
authors: Pardasaney
authors: Nancy K
authors: NK
authors: Latham
authors: Alan M
authors: AM
authors: Jette
authors: Robert C
authors: RC
authors: Wagenaar
authors: Pengsheng
authors: P
authors: Ni
authors: Mary D
authors: MD
authors: Slavin
authors: Jonathan F
authors: JF
authors: Bean
mesh_terms: D000058:Accidental Falls / Q000517:prevention & control*; D000222:Adaptation, Physiological; D000368:Aged; D000369:Aged, 80 and over; D016001:Confidence Intervals; D005081:Exercise Therapy / Q000379:methods*; D005260:Female; D005684:Gait / Q000502:physiology; D015577:Geriatric Assessment; D006801:Humans; D008297:Male; D004856:Postural Balance / Q000502:physiology*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012307:Risk Factors; D012680:Sensitivity and Specificity; D016037:Single-Blind Method