title: Designing clinical trials for assessing the effects of cognitive training and physical activity interventions on cognitive outcomes: the Seniors Health and Activity Research Program Pilot (SHARP-P) study, a randomized controlled trial.
abstract: BACKGROUND
  The efficacy of non-pharmacological intervention approaches such as physical activity, strength, and cognitive training for improving brain health has not been established. Before definitive trials are mounted, important design questions on participation/adherence, training and interventions effects must be answered to more fully inform a full-scale trial.
  
  
  METHODS
  SHARP-P was a single-blinded randomized controlled pilot trial of a 4-month physical activity training intervention (PA) and/or cognitive training intervention (CT) in a 2 × 2 factorial design with a health education control condition in 73 community-dwelling persons, aged 70-85 years, who were at risk for cognitive decline but did not have mild cognitive impairment.
  
  
  RESULTS
  Intervention attendance rates were higher in the CT and PACT groups: CT: 96%, PA: 76%, PACT: 90% (p=0.004), the interventions produced marked changes in cognitive and physical performance measures (p≤0.05), and retention rates exceeded 90%. There were no statistically significant differences in 4-month changes in composite scores of cognitive, executive, and episodic memory function among arms. Four-month improvements in the composite measure increased with age among participants assigned to physical activity training but decreased with age for other participants (intervention*age interaction p=0.01). Depending on the choice of outcome, two-armed full-scale trials may require fewer than 1,000 participants (continuous outcome) or 2,000 participants (categorical outcome).
  
  
  CONCLUSIONS
  Good levels of participation, adherence, and retention appear to be achievable for participants through age 85 years. Care should be taken to ensure that an attention control condition does not attenuate intervention effects. Depending on the choice of outcome measures, the necessary sample sizes to conduct four-year trials appear to be feasible.
  
  
  BACKGROUND
  Clinicaltrials.gov Identifier: NCT00688155.
authors: Division of Public Health Sciences, Department of Biostatistical Sciences - Wachovia 21st floor, Medical Center Boulevard, Winston-Salem, North Carolina 27157, USA. clegault@wfubmc.edu
authors: Claudine
authors: C
authors: Legault
authors: Janine M
authors: JM
authors: Jennings
authors: Jeffrey A
authors: JA
authors: Katula
authors: Dale
authors: D
authors: Dagenbach
authors: Sarah A
authors: SA
authors: Gaussoin
authors: Kaycee M
authors: KM
authors: Sink
authors: Stephen R
authors: SR
authors: Rapp
authors: W Jack
authors: WJ
authors: Rejeski
authors: Sally A
authors: SA
authors: Shumaker
authors: Mark A
authors: MA
authors: Espeland
references: J Gerontol A Biol Sci Med Sci. 2008 Sep;63(9):997-1004
references: 18840807
references: Int J Geriatr Psychiatry. 2000 Nov;15(11):983-91
references: 11113976
references: Ann Intern Med. 2000 Sep 19;133(6):464-70
references: 10975965
references: Neuropsychol Dev Cogn B Aging Neuropsychol Cogn. 2005 Sep;12(3):278-98
references: 24428336
references: Front Aging Neurosci. 2010 Jun 07;2:23
references: 20589103
references: Neuroimage. 2010 Oct 1;52(4):1667-76
references: 20580844
references: J Clin Psychiatry. 1987 Aug;48(8):314-8
references: 3611032
references: Arch Intern Med. 2010 Jan 25;170(2):170-8
references: 20101012
references: Psychosom Med. 1997 Jul-Aug;59(4):362-71
references: 9251155
references: Obes Res. 2004 Sep;12(9):1426-34
references: 15483207
references: J Aging Phys Act. 2009 Jul;17(3):294-306
references: 19799101
references: Proc Natl Acad Sci U S A. 2006 Aug 15;103(33):12523-8
references: 16888038
references: Behav Ther. 2006 Jun;37(2):120-30
references: 16823465
references: Am J Prev Med. 2003 Oct;25(3 Suppl 2):172-83
references: 14552942
references: Int J Geriatr Psychiatry. 2011 Feb;26(2):135-43
references: 21229597
references: Arch Intern Med. 2010 Jan 25;170(2):162-9
references: 20101011
references: Clin Trials. 2006;3(2):99-106
references: 16773952
references: Psychosom Med. 2010 Apr;72(3):239-52
references: 20223924
references: Arch Neurol. 2010 Jan;67(1):71-9
references: 20065132
references: Arch Gerontol Geriatr. 2009 May-Jun;48(3):284-6
references: 18374429
references: Contemp Clin Trials. 2005 Apr;26(2):141-54
references: 15837437
references: JAMA. 2003 May 21;289(19):2554-9
references: 12759327
references: Clin Geriatr Med. 2010 Feb;26(1):1-16
references: 20176289
references: Psychol Sci. 2003 Mar;14(2):125-30
references: 12661673
references: Int J Sports Med. 2002 Aug;23(6):415-21
references: 12215960
references: J Gerontol A Biol Sci Med Sci. 2010 Jun;65(6):680-8
references: 20418350
references: Br J Sports Med. 2009 Jan;43(1):22-4
references: 18927158
references: J Gerontol A Biol Sci Med Sci. 2009 Jun;64(6):688-94
references: 19244157
references: J Int Neuropsychol Soc. 2007 Jan;13(1):120-31
references: 17166311
references: Hypertension. 2010 Jun;55(6):1331-8
references: 20305128
references: Am J Geriatr Psychiatry. 2009 Nov;17(11):976-85
references: 20104055
references: J Alzheimers Dis. 2010;20(3):915-24
references: 20413867
references: Ann Intern Med. 2010 Aug 3;153(3):182-93
references: 20547887
references: J Consult Clin Psychol. 2003 Dec;71(6):973-9
references: 14622072
references: Med Sci Sports Exerc. 2007 Nov;39(11):1997-2004
references: 17986908
references: Eur J Appl Physiol. 2010 Jul;109(4):617-24
references: 20186426
references: Trials. 2009 Dec 14;10:114
references: 20003398
references: BMC Med Res Methodol. 2006 Jun 24;6:29
references: 16796762
references: Acta Psychol (Amst). 1999 Apr;101(2-3):339-78
references: 10344190
references: Neuropsychologia. 1982;20(3):249-62
references: 7121793
references: Psychol Aging. 1989 Dec;4(4):500-3
references: 2619956
references: J Intern Med. 2004 Sep;256(3):240-6
references: 15324367
references: J Gerontol A Biol Sci Med Sci. 2006 Nov;61(11):1157-65
references: 17167156
references: J Geriatr Psychiatry Neurol. 2007 Dec;20(4):239-49
references: 18004010
references: J Cogn Neurosci. 1997 Jul;9(4):462-75
references: 23968211
references: Med Sci Sports Exerc. 2007 Aug;39(8):1435-45
references: 17762378