title: Large-scale application of a telephone-based test of cognitive functioning in older adults.
abstract: OBJECTIVE
  The study of cognitive functioning in large epidemiological settings is hampered by a lack of instruments for the remote assessment of cognitive performance, especially when targeting variability across the full range of adult functioning. The present study examined the practicability of such investigations using a recently developed telephone interview (Cognitive Telephone Screening Instrument, COGTEL).
  
  
  METHODS
  A subcohort of an ongoing epidemiological study in the elderly German population (ESTHER) was interviewed via telephone by trained personnel. These data were combined with sociodemographic information obtained by standardized self-administered questionnaires, and analysed by tabulation, histograms and regression models.
  
  
  RESULTS
  A total of 1,697 interviews could be analysed. The eligible participants had a mean age ± standard deviation of 74.0 ± 2.8 years. The COGTEL total scores closely followed a normal distribution with no evidence of a ceiling effect. In adjusted regression models, COGTEL total and subcomponent scores were negatively associated with age and strongly positively with higher education, whereas the association with sex was less consistent.
  
  
  CONCLUSIONS
  The results suggest that the COGTEL can readily be administered to large study populations and produces plausible and informative results. Education should be considered in all investigations using this instrument and requires further in-depth analyses. Future studies will need to elucidate its associations with risk factors and its prognostic potential for cognitive decline and dementia.
authors.affiliation: German Cancer Research Center, Heidelberg, Germany. L.Breitling@dkfz.de
authors.forename: Lutz P
authors.initials: LP
authors.lastname: Breitling
authors.forename: Melanie
authors.initials: M
authors.lastname: Wolf
authors.forename: Heiko
authors.initials: H
authors.lastname: Müller
authors.forename: Elke
authors.initials: E
authors.lastname: Raum
authors.forename: Matthias
authors.initials: M
authors.lastname: Kliegel
authors.forename: Hermann
authors.initials: H
authors.lastname: Brenner
mesh_terms: D000368:Aged; D003071:Cognition; D003072:Cognition Disorders / Q000175:diagnosis*; D015331:Cohort Studies; D004522:Educational Status; D005260:Female; D005858:Germany; D006801:Humans; D008297:Male; D008403:Mass Screening / Q000379:methods*; D008875:Middle Aged; D009483:Neuropsychological Tests; D011159:Population Surveillance / Q000379:methods*; D011446:Prospective Studies; D019114:Remote Consultation / Q000379:methods*; D012959:Socioeconomic Factors