title: The impact of distance and duration of travel on participation rates and participants' satisfaction: results from a pilot study at one study centre in Pretest 2 of the German National Cohort.
abstract: OBJECTIVE
  In this pilot study within the Pretest 2 phase of the German National Cohort, we aimed to (1) test the hypothesis that distance and duration of travel to a study centre may affect participation rates and participants' satisfaction and (2) to obtain data that would help to select recruitment areas around the study centre Hannover with the greatest projected participation rate for the main study.
  
  
  METHODS
  Mixed urban/suburban environment in Northern Germany with approximately 600,000 inhabitants. 4 recruitment areas with divergent estimated mean distances (range, 7-40 km) and duration of travel to the study centre Hannover were selected.
  
  
  METHODS
  1050 men and women (ratio, 1:1), aged 20-69 years, were randomly selected from the population registries of the 4 recruitment areas and invited by mail to participate in the Pretest 2 study programme at the study centre Hannover, covering a variety of questionnaire-based and physical assessments. 166 individuals participated (16%).
  
  
  METHODS
  All 166 participants completed a travel questionnaire containing 5 items relating to travel duration and satisfaction, amounting to a participation rate of 100% in the questionnaire-based part of the study.
  
  
  RESULTS
  Participation rates in the Pretest 2 programme at the study centre Hannover by area ranged from 11% (area farthest from the study centre, estimated median distance 38 km) to 18% (nearest area, 2 km). The odds of non-participation were highest in the area farthest from the study centre (adjusted OR 2.06; p=0.01; CI 1.28 to 3.32). Nonetheless, 97% of participants were satisfied with travel duration.
  
  
  CONCLUSIONS
  Increasing distance was associated with a lower participation rate. However, acceptance of duration of travel was high, irrespective of distance or duration. Thus, recruiting in farther away locations may select individuals with a greater frustration tolerance for travel to the study centre, perhaps due to a greater interest in participating in health-oriented studies and thus different health-related behaviour.
authors: Department of Epidemiology, Helmholtz Centre for Infection Research, Braunschweig, Lower Saxony, Germany.
authors: Aparna
authors: A
authors: Schweitzer
authors: Department of Epidemiology, Helmholtz Centre for Infection Research, Braunschweig, Lower Saxony, Germany TWINCORE Centre for Experimental and Clinical Infection Research, Hannover, Germany.
authors: Manas K
authors: MK
authors: Akmatov
authors: Department of Epidemiology, Helmholtz Centre for Infection Research, Braunschweig, Lower Saxony, Germany.
authors: Florentina
authors: F
authors: Kindler
authors: Department of Epidemiology, Helmholtz Centre for Infection Research, Braunschweig, Lower Saxony, Germany.
authors: Yvonne
authors: Y
authors: Kemmling
authors: Institute for Biometry, Epidemiology and Information Processing, University of Veterinary Medicine, Hannover, Germany.
authors: Lothar
authors: L
authors: Kreienbrock
authors: Department of Epidemiology, Helmholtz Centre for Infection Research, Braunschweig, Lower Saxony, Germany Hannover Medical School, Hannover, Germany.
authors: Gérard
authors: G
authors: Krause
authors: Department of Epidemiology, Helmholtz Centre for Infection Research, Braunschweig, Lower Saxony, Germany TWINCORE Centre for Experimental and Clinical Infection Research, Hannover, Germany.
authors: Frank
authors: F
authors: Pessler
mesh_terms: D000328:Adult; D001290:Attitude; D015331:Cohort Studies; D016021:Epidemiologic Studies; D005260:Female; D005858:Germany; D006801:Humans; D008297:Male; D008875:Middle Aged; D010549:Personal Satisfaction; D010865:Pilot Projects; D011159:Population Surveillance; D035842:Research Subjects; D011795:Surveys and Questionnaires; D014186:Transportation; D014195:Travel
keywords: EPIDEMIOLOGY; SOCIAL MEDICINE