title: Parkinson's Disease Case Ascertainment in the EPIC Cohort: The NeuroEPIC4PD Study.
abstract: OBJECTIVE
  Large epidemiological prospective studies represent an important opportunity for investigating risk factors for rare diseases such as Parkinson's disease (PD). Here we describe the procedures we used for ascertaining PD cases in the EPIC (European Prospective Investigation into Cancer and Nutrition) study.
  
  
  METHODS
  The following three-phase procedure was used: (1) elaboration of a NeuroEPIC4PD template for clinical data collection, (2) identification of all potential PD cases via record linkage and (3) validation of the diagnosis through clinical record revision, in a population of 220,494 subjects recruited in 7 European countries. All cases were labelled with the NeuroEPIC4PD diagnoses of 'definite', 'very likely', 'probable', or 'possible' PD.
  
  
  RESULTS
  A total of 881 PD cases were identified, with over 2,741,780 person-years of follow-up (199 definite, 275 very likely, 146 probable, and 261 possible). Of these, 734 were incident cases. The mean age at diagnosis was 67.9 years (SD 9.2) and 458 patients (52.0%) were men. Bradykinesia was the most frequent presenting motor sign (76.5%). Tremor-dominant and akinetic rigid forms of PD were the most common types of PD. A total of 289 patients (32.8%) were dead at the time of the last follow-up.
  
  
  CONCLUSIONS
  This exercise proved that it is feasible to ascertain PD in large population-based cohort studies and offers a potential framework to be replicated in similar studies.
authors.affiliation: School of Public Health, Imperial College London, London, UK.
authors.forename: Valentina
authors.initials: V
authors.lastname: Gallo
authors.forename: Carol
authors.initials: C
authors.lastname: Brayne
authors.forename: Lars
authors.initials: L
authors.lastname: Forsgren
authors.forename: Roger A
authors.initials: RA
authors.lastname: Barker
authors.forename: Jesper
authors.initials: J
authors.lastname: Petersson
authors.forename: Oskar
authors.initials: O
authors.lastname: Hansson
authors.forename: Daniel
authors.initials: D
authors.lastname: Lindqvist
authors.forename: Claudio
authors.initials: C
authors.lastname: Ruffmann
authors.forename: Lianna
authors.initials: L
authors.lastname: Ishihara
authors.forename: Robert
authors.initials: R
authors.lastname: Luben
authors.forename: Larraitz
authors.initials: L
authors.lastname: Arriola
authors.forename: Alberto
authors.initials: A
authors.lastname: Bergareche
authors.forename: Diana
authors.initials: D
authors.lastname: Gavrila
authors.forename: Maria Elena
authors.initials: ME
authors.lastname: Erro
authors.forename: Nicola
authors.initials: N
authors.lastname: Vanacore
authors.forename: Carlotta
authors.initials: C
authors.lastname: Sacerdote
authors.forename: Bas
authors.initials: B
authors.lastname: Bueno-de-Mesquita
authors.forename: Roel
authors.initials: R
authors.lastname: Vermeulen
authors.forename: Meinie
authors.initials: M
authors.lastname: Seelen
authors.forename: Sabina
authors.initials: S
authors.lastname: Sieri
authors.forename: Giovanna
authors.initials: G
authors.lastname: Masala
authors.forename: Silvia
authors.initials: S
authors.lastname: Ramat
authors.forename: Andreas
authors.initials: A
authors.lastname: Kyrozis
authors.forename: Antonia
authors.initials: A
authors.lastname: Thricopolou
authors.forename: Salvatore
authors.initials: S
authors.lastname: Panico
authors.forename: Amalia
authors.initials: A
authors.lastname: Mattiello
authors.forename: Rudolf
authors.initials: R
authors.lastname: Kaaks
authors.forename: Birgit
authors.initials: B
authors.lastname: Teucher
authors.forename: Verena
authors.initials: V
authors.lastname: Katzke
authors.forename: Manja
authors.initials: M
authors.lastname: Kloss
authors.forename: Lisa
authors.initials: L
authors.lastname: Curry
authors.forename: Federico
authors.initials: F
authors.lastname: Calboli
authors.forename: Elio
authors.initials: E
authors.lastname: Riboli
authors.forename: Paolo
authors.initials: P
authors.lastname: Vineis
authors.forename: Lefkos
authors.initials: L
authors.lastname: Middleton
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D018476:Hypokinesia / Q000150:complications / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000150:complications / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy; D011446:Prospective Studies; D012307:Risk Factors