Including questionnaires with the invitation package appeared to increase the response fraction among women

Pierra A. Rogers, Livia Haddow, Allyson K. Thomson, Lin Fritschi, Jen Girschik, Terry Boyle, Sonia El Zaemey, Jane S. Heyworth

Research output: Contribution to journalArticlepeer-review

4 Citations (Scopus)


Objective: The Breast Cancer Environment and Employment Study (BCEES) is a case-control study that began in 2009. The study experienced a lower than expected response fraction, a trend that appears to be occurring internationally. A 32-page questionnaire was included in the initial invitation to participate, and previous research suggests that long questionnaires decrease response fractions. The aim of this study was to test whether removal of the questionnaire from the invitation package increased participation. Study Design and Setting: A randomized controlled trial was undertaken among the BCEES controls from June to August 2010. One group of 250 received the questionnaire in the initial invitation package, and the other group of 250 received only the invitation package and was sent the questionnaire after their consent was received. The proportion of responses for the two groups was compared using contingency tables and chi-square statistics. Results: Those who received the questionnaire with the invitation package were more likely to consent to participate than those who did not (40.8% and 33.2%, respectively). However, this difference was not statistically significant (P = 0.078). Conclusion: To improve response fractions and reduce time in following up nonresponses, questionnaires should be included in the invitation package.

Original languageEnglish
Pages (from-to)696-699
Number of pages4
JournalJournal of Clinical Epidemiology
Issue number6
Publication statusPublished or Issued - Jun 2012
Externally publishedYes


  • Invitation to participate
  • Questionnaire length
  • Randomized controlled trial
  • Response fraction
  • Response rate
  • Survey methods

ASJC Scopus subject areas

  • Epidemiology

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