title: The Feasibility of At-Home iPad Cognitive Testing For Use in Clinical Trials.
abstract: BACKGROUND
  Technological advances now make it feasible to administer cognitive assessments at-home on mobile and touch-screen devices such as an iPad or tablet computer. Validation of these techniques is necessary to assess their utility in clinical trials.
  
  
  OBJECTIVE
  We used a Computerized Cognitive Composite for Preclinical Alzheimer's Disease (C3-PAD) developed for iPad 1) to determine the feasibility of performing the C3-PAD at home by older individuals without the presence of a trained psychometrician; 2) to explore the reliability of in-clinic compared to at-home C3-PAD performance and 3) to examine the comparability of C3-PAD performance to standardized neuropsychological tests.
  
  
  METHODS
  Forty-nine cognitively normal older individuals (mean age, 71.467.7 years; 20% non-Caucasian) were recruited from research centers at the Massachusetts General Hospital and Brigham and Women's Hospital. Participants made two in-clinic visits one-week apart and took five 30-minute alternate versions of the C3-PAD at-home measuring episodic memory, reaction time and working memory.
  
  
  METHODS
  A reliability analysis explored equivalence of the six alternate C3-PAD test versions. A feasibility assessment calculated the percentage of individuals who completed all at-home tests correctly, in contrast to incomplete assessments. Correlational analyses examined the association between C3-PAD-clinic compared to C3-PAD-home assessments and between C3-PAD performance and standardized paper and pencil tests.
  
  
  RESULTS
  Excellent reliability was observed among the 6 C3-PAD alternate versions (Cronbach alpha coefficient=0.93). A total of 28 of 49 participants completed all at-home sessions correctly and 48 of 49 completed four out of five correctly. There were no significant differences in participant age, sex or education between complete and incomplete at-home assessments. A single in-clinic C3-PAD assessment and the at-home C3-PAD assessments were highly associated with each other (r2=0.508, p<0.0001), suggesting that at-home tests provide reliable data as in-clinic assessments. There was also a moderate association between the at-home C3-PAD assessments and the in-clinic standardized paper and pencil tests covering similar cognitive domains (r2= 0.168, p< 0.003).
  
  
  CONCLUSIONS
  Reliable and valid cognitive data can be obtained from the C3-PAD assessments in the home environment. With initial in-clinic training, a high percentage of older individuals completed at-home assessments correctly. At-home cognitive testing shows promise for inclusion into clinical trial designs.
authors.affiliation: Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA; Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, USA.
authors.forename: Dorene M
authors.initials: DM
authors.lastname: Rentz
authors.affiliation: Boston University, Boston, MA USA.
authors.forename: Maria
authors.initials: M
authors.lastname: Dekhtyar
authors.affiliation: University of Chicago, Chicago, IL USA.
authors.forename: Julia
authors.initials: J
authors.lastname: Sherman
authors.affiliation: Commonwealth Scientific and Industrial Research Organization (CSIRO), eHealth Wembley, Western Australia.
authors.forename: Samantha
authors.initials: S
authors.lastname: Burnham
authors.affiliation: Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA.
authors.forename: Deborah
authors.initials: D
authors.lastname: Blacker
authors.affiliation: Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, USA.
authors.forename: Sarah L
authors.initials: SL
authors.lastname: Aghjayan
authors.affiliation: Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, USA.
authors.forename: Kathryn V
authors.initials: KV
authors.lastname: Papp
authors.affiliation: Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA; Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, USA.
authors.forename: Rebecca E
authors.initials: RE
authors.lastname: Amariglio
authors.affiliation: CogState, Ltd., Melbourne, Australia.
authors.forename: Adrian
authors.initials: A
authors.lastname: Schembri
authors.affiliation: CogState, Ltd., Melbourne, Australia.
authors.forename: Tanya
authors.initials: T
authors.lastname: Chenhall
authors.affiliation: CogState, Ltd., Melbourne, Australia.
authors.forename: Paul
authors.initials: P
authors.lastname: Maruff
authors.affiliation: University of California at San Diego, San Diego CA USA.
authors.forename: Paul
authors.initials: P
authors.lastname: Aisen
authors.affiliation: Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA.
authors.forename: Bradley T
authors.initials: BT
authors.lastname: Hyman
authors.affiliation: Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA; Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, USA.
authors.forename: Reisa A
authors.initials: RA
authors.lastname: Sperling
keywords: computerized assessment of cognitive function; home-based assessment; prevention trials