title: A randomised controlled trial and cost-effectiveness evaluation of 'booster' interventions to sustain increases in physical activity in middle-aged adults in deprived urban neighbourhoods.
abstract: BACKGROUND
  More evidence is needed on the potential role of 'booster' interventions in the maintenance of increases in physical activity levels after a brief intervention in relatively sedentary populations.
  
  
  OBJECTIVE
  To determine whether objectively measured physical activity, 6 months after a brief intervention, is increased in those receiving physical activity 'booster' consultations delivered in a motivational interviewing (MI) style, either face to face or by telephone.
  
  
  METHODS
  Three-arm, parallel-group, pragmatic, superiority randomised controlled trial with nested qualitative research fidelity and geographical information systems and health economic substudies. Treatment allocation was carried out using a web-based simple randomisation procedure with equal allocation probabilities. Principal investigators and study statisticians were blinded to treatment allocation until after the final analysis only.
  
  
  METHODS
  Deprived areas of Sheffield, UK.
  
  
  METHODS
  Previously sedentary people, aged 40-64 years, living in deprived areas of Sheffield, UK, who had increased their physical activity levels after receiving a brief intervention.
  
  
  METHODS
  Participants were randomised to the control group (no further intervention) or to two sessions of MI, either face to face ('full booster') or by telephone ('mini booster'). Sessions were delivered 1 and 2 months post-randomisation.
  
  
  METHODS
  The primary outcome was total energy expenditure (TEE) per day in kcal from 7-day accelerometry, measured using an Actiheart device (CamNtech Ltd, Cambridge, UK). Independent evaluation of practitioner competence was carried out using the Motivational Interviewing Treatment Integrity assessment. An estimate of the per-participant intervention costs, resource use data collected by questionnaire and health-related quality of life data were analysed to produce a range of economic models from a short-term NHS perspective. An additional series of models were developed that used TEE values to estimate the long-term cost-effectiveness.
  
  
  RESULTS
  In total, 282 people were randomised (control = 96; mini booster = 92, full booster = 94) of whom 160 had a minimum of 4 out of 7 days' accelerometry data at 3 months (control = 61, mini booster = 47, full booster = 52). The mean difference in TEE per day between baseline and 3 months favoured the control arm over the combined booster arm but this was not statistically significant (-39 kcal, 95% confidence interval -173 to 95, p = 0.57). The autonomy-enabled MI communication style was generally acceptable, although some participants wanted a more paternalistic approach and most expressed enthusiasm for monitoring and feedback components of the intervention and research. Full boosters were more popular than mini boosters. Practitioners achieved and maintained a consistent level of MI competence. Walking distance to the nearest municipal green space or leisure facilities was not associated with physical activity levels. Two alternative modelling approaches both suggested that neither intervention was likely to be cost-effective.
  
  
  CONCLUSIONS
  Although some individuals do find a community-based, brief MI 'booster' intervention supportive, the low levels of recruitment and retention and the lack of impact on objectively measured physical activity levels in those with adequate outcome data suggest that it is unlikely to represent a clinically effective or cost-effective intervention for the maintenance of recently acquired physical activity increases in deprived middle-aged urban populations. Future research with middle-aged and relatively deprived populations should explore interventions to promote physical activity that require less proactive engagement from individuals, including environmental interventions.
  
  
  BACKGROUND
  Current Controlled Trials ISRCTN56495859, ClinicalTrials.gov NCT00836459.
  
  
  BACKGROUND
  This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 18, No. 13. See the NIHR Journals Library website for further project information.
authors.affiliation: School of Health and Related Research (ScHARR), University of Sheffield, Sheffield, UK.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Goyder
authors.affiliation: Sheffield Clinical Trials Research Unit, University of Sheffield, Sheffield, UK.
authors.forename: Daniel
authors.initials: D
authors.lastname: Hind
authors.affiliation: Centre for Sport and Exercise Science, Sheffield Hallam University, Sheffield, UK.
authors.forename: Jeff
authors.initials: J
authors.lastname: Breckon
authors.affiliation: Sheffield Clinical Trials Research Unit, University of Sheffield, Sheffield, UK.
authors.forename: Munyaradzi
authors.initials: M
authors.lastname: Dimairo
authors.affiliation: School of Health and Related Research (ScHARR), University of Sheffield, Sheffield, UK.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Minton
authors.affiliation: School of Health and Related Research (ScHARR), University of Sheffield, Sheffield, UK.
authors.forename: Emma
authors.initials: E
authors.lastname: Everson-Hock
authors.affiliation: School of Health and Related Research (ScHARR), University of Sheffield, Sheffield, UK.
authors.forename: Simon
authors.initials: S
authors.lastname: Read
authors.affiliation: Centre for Sport and Exercise Science, Sheffield Hallam University, Sheffield, UK.
authors.forename: Robert
authors.initials: R
authors.lastname: Copeland
authors.affiliation: Centre for Sport and Exercise Science, Sheffield Hallam University, Sheffield, UK.
authors.forename: Helen
authors.initials: H
authors.lastname: Crank
authors.affiliation: School of Health and Related Research (ScHARR), University of Sheffield, Sheffield, UK.
authors.forename: Kimberly
authors.initials: K
authors.lastname: Horspool
authors.affiliation: Centre for Sport and Exercise Science, Sheffield Hallam University, Sheffield, UK.
authors.forename: Liam
authors.initials: L
authors.lastname: Humphreys
authors.affiliation: Centre for Sport and Exercise Science, Sheffield Hallam University, Sheffield, UK.
authors.forename: Andrew
authors.initials: A
authors.lastname: Hutchison
authors.affiliation: Centre for Sport and Exercise Science, Sheffield Hallam University, Sheffield, UK.
authors.forename: Sue
authors.initials: S
authors.lastname: Kesterton
authors.affiliation: School of Health and Related Research (ScHARR), University of Sheffield, Sheffield, UK.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Latimer
authors.affiliation: School of Health and Related Research (ScHARR), University of Sheffield, Sheffield, UK.
authors.forename: Emma
authors.initials: E
authors.lastname: Scott
authors.affiliation: Centre for Sport and Exercise Science, Sheffield Hallam University, Sheffield, UK.
authors.forename: Peter
authors.initials: P
authors.lastname: Swaile
authors.affiliation: School of Health and Related Research (ScHARR), University of Sheffield, Sheffield, UK.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Walters
authors.affiliation: Centre for Sport and Exercise Science, Sheffield Hallam University, Sheffield, UK.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Wood
authors.affiliation: Centre for Health and Social Care Research, Sheffield Hallam University, Sheffield, UK.
authors.forename: Karen
authors.initials: K
authors.lastname: Collins
authors.affiliation: Sheffield Clinical Trials Research Unit, University of Sheffield, Sheffield, UK.
authors.forename: Cindy
authors.initials: C
authors.lastname: Cooper
mesh_terms: D000328:Adult; D003362:Cost-Benefit Analysis; D015444:Exercise / Q000502:physiology*; D005260:Female; D006293:Health Promotion / Q000458:organization & administration*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D010349:Patient Compliance / Q000706:statistics & numerical data*; D011203:Poverty; D015397:Program Evaluation; D011788:Quality of Life; D040242:Risk Reduction Behavior; D057185:Sedentary Behavior; D006113:United Kingdom; D014505:Urban Population