title: The effect of a dual task on gait speed in community dwelling older adults: A systematic review and meta-analysis.
abstract: OBJECTIVE
  Reduced walking speed in older adults is associated with adverse health outcomes. This review aims to examine the effect of a cognitive dual-task on the gait speed of community-dwelling older adults with no significant pathology affecting gait.
  
  
  METHODS
  Electronic database searches were performed in, Web of Science, PubMed, SCOPUS, Embase and psychINFO. Eligibility and methodological quality was assessed by two independent reviewers. The effect size on gait speed was measured as the raw mean difference (95% confidence interval) between single and dual-task performance. Pooled estimates of the overall effect were computed using a random effects method and forest plots generated.
  
  
  METHODS
  22 studies (27 data sets) with a population of 3728 were reviewed and pooled for meta-analysis. The mean walking speed of participants included in all studies was >1.0m/s and all studies reported the effect of a cognitive dual-task on gait speed. Sub-analysis examined the effect of type of cognitive task (mental-tracking vs. verbal-fluency). Mean single-task gait speed was 1.21 (0.13)m/s, the addition of a dual-task reduced speed by 0.19 m/s to 1.02 (0.16)m/s (p<0.00001), both mental-tracking and verbal-fluency tasks resulted in significant reduction in gait speed.
  
  
  CONCLUSIONS
  The cross-sectional design of the studies made quality assessment difficult. Despite efforts, high heterogeneity remained, possibly due to participant characteristics and testing protocols. This meta-analysis shows that in community-dwelling older adults, the addition of a dual-task significantly reduces gait speed and may indicate the value of including dual-task walking as part of the standard clinical assessment of older people.
authors.affiliation: University College Dublin, School of Public Health, Physiotherapy and Sports Science, Health Sciences Centre, Belfield, Dublin 4, Ireland; Health Service Executive, Physiotherapy Department, Louth PCS, Dundalk, Ireland. Electronic address: erin.smith@hse.ie.
authors.forename: Erin
authors.initials: E
authors.lastname: Smith
authors.affiliation: University College Dublin, School of Public Health, Physiotherapy and Sports Science, Health Sciences Centre, Belfield, Dublin 4, Ireland. Electronic address: t.cusack@ucd.ie.
authors.forename: Tara
authors.initials: T
authors.lastname: Cusack
authors.affiliation: University College Dublin, School of Public Health, Physiotherapy and Sports Science, Health Sciences Centre, Belfield, Dublin 4, Ireland. Electronic address: c.blake@ucd.ie.
authors.forename: Catherine
authors.initials: C
authors.lastname: Blake
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003071:Cognition / Q000502:physiology*; D005684:Gait / Q000502:physiology*; D006801:Humans; D057187:Independent Living; D015233:Models, Statistical; D013647:Task Performance and Analysis; D016138:Walking / Q000502:physiology* / Q000523:psychology
keywords: Dual-task; Gait speed; Meta-analysis; Older adults