title: Internet-based data inclusion in a population-based European collaborative follow-up study of inflammatory bowel disease patients: description of methods used and analysis of factors influencing response rates.
abstract: OBJECTIVE
  To describe an Internet-based data acquisition facility for a European 10-year clinical follow-up study project of a population-based cohort of inflammatory bowel disease (IBD) patients and to investigate the influence of demographic and disease related patient characteristics on response rates.
  
  
  METHODS
  Thirteen years ago, the European Collaborative study group of IBD (EC-IBD) initiated a population-based prospective inception cohort of 2 201 uniformly diagnosed IBD patients within 20 well-described geographical areas in 11 European countries and Israel. For the 10-year follow-up of this cohort, an electronic patient questionnaire (ePQ) and electronic physician per patient follow-up form (ePpPFU) were designed as two separate data collecting instruments and made available through an Internet-based website. Independent demographic and clinical determinants of ePQ participation were analyzed using multivariate logistic regression.
  
  
  RESULTS
  In 958 (316 CD and 642 UC) out of a total number of 1 505 (64%) available IBD patients, originating from 13 participating centers from nine different countries, both ePQ and ePpPFU were completed. Patients older than 40 years at ePQ completion (OR: 1.53 (95%CI: 1.14-2.05)) and those with active disease during the 3 mo previous to ePQ completion (OR: 3.32 (95%CI: 1.57-7.03)) were significantly more likely to respond.
  
  
  CONCLUSIONS
  An Internet-based data acquisition tool appeared successful in sustaining a unique Western-European and Israelian multi-center 10-year clinical follow-up study project in patients afflicted with IBD.
authors.affiliation: Department of Gastroenterology and Hepatology, PO box 5800, 6202 AZ Maastricht, The Netherlands. frankwolters@ace-on-air.nl
authors.forename: Frank L
authors.initials: FL
authors.lastname: Wolters
authors.forename: Gilbert
authors.initials: G
authors.lastname: van Zeijl
authors.forename: Jildou
authors.initials: J
authors.lastname: Sijbrandij
authors.forename: Frederik
authors.initials: F
authors.lastname: Wessels
authors.forename: Colm
authors.initials: C
authors.lastname: O'Morain
authors.forename: Charles
authors.initials: C
authors.lastname: Limonard
authors.forename: Maurice G
authors.initials: MG
authors.lastname: Russel
authors.forename: Reinhold W
authors.initials: RW
authors.lastname: Stockbrugger
mesh_terms: D000328:Adult; D015331:Cohort Studies; D003627:Data Interpretation, Statistical; D005060:Europe; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015212:Inflammatory Bowel Diseases; D020407:Internet; D007557:Israel; D008297:Male; D011795:Surveys and Questionnaires