title: A randomized trial of survey participation in a national random sample of general practitioners and gynecologists in France.
abstract: BACKGROUND
  Healthcare professionals play a critical role in women's choice of contraceptive methods. However, national surveys on sexual and reproductive health (SRH) among physicians are rare and present low participation rates. We conducted a randomized trial to test for the effectiveness of three interventions to improve survey participation of private physicians delivering reproductive health services in France.
  
  
  METHODS
  The study comprised a national random sample of 500 general practitioners and 500 gynecologists working in private offices. All received a postal invitation to participate either by completing a paper, phone or online questionnaire. Physicians were randomly assigned to six groups to test for the effect of three interventions: a non-monetary incentive in the form of a scientific book, telephone contact, and the possibility of completing the questionnaire by phone.
  
  
  RESULTS
  Overall, 362 questionnaires were collected (26 online, 2 by phone) and 58 physicians were ineligible. The completion rate increased from 26.7% in physicians who received no intervention to 42.7% in those who received the book and a phone call. The phone call increased the completion rate by 11% percentage points (P=0.01), while the book had no significant effect. Results from multivariate logistic regressions also indicate that gynecologists (OR=1.6) and female physicians (OR=1.5) were more likely to participate than others.
  
  
  CONCLUSIONS
  The results suggest that phone calls substantially increase participation of physicians in sexual and reproductive health surveys but have little impact on sampling distortion. Differentials in response rates by physicians' characteristics should be considered in future SRH studies among physicians.
authors.affiliation: Institut national des études démographiques (INED), 133, boulevard Davout, Paris, France; INSERM, U669, 75014 Paris, France; Université Paris-Sud and université Paris Descartes, UMRS 0669, 75014 Paris, France. Electronic address: stephane.legleye@ined.fr.
authors.forename: S
authors.initials: S
authors.lastname: Legleye
authors.affiliation: Gender, Sexual and Reproductive Health, CESP Centre for Research in Epidemiology and Population Health, U1018, INSERM, 94807 Le Kremlin-Bicêtre, France.
authors.forename: A
authors.initials: A
authors.lastname: Bohet
authors.affiliation: Institut national des études démographiques (INED), 133, boulevard Davout, Paris, France.
authors.forename: N
authors.initials: N
authors.lastname: Razafindratsima
authors.affiliation: Institut national des études démographiques (INED), 133, boulevard Davout, Paris, France; Gender, Sexual and Reproductive Health, CESP Centre for Research in Epidemiology and Population Health, U1018, INSERM, 94807 Le Kremlin-Bicêtre, France; Université Paris-Sud 11, UMRS 1018, 94807 Le Kremlin-Bicêtre, France.
authors.forename: N
authors.initials: N
authors.lastname: Bajos
authors.affiliation: Institut national des études démographiques (INED), 133, boulevard Davout, Paris, France; Gender, Sexual and Reproductive Health, CESP Centre for Research in Epidemiology and Population Health, U1018, INSERM, 94807 Le Kremlin-Bicêtre, France; Université Paris-Sud 11, UMRS 1018, 94807 Le Kremlin-Bicêtre, France; Department of Population, Family and Reproductive Health, Johns Hopkins Bloomberg School of Public Health, 615, North Wolfe Street, Baltimore, MD 21205, USA.
authors.forename: C
authors.initials: C
authors.lastname: Moreau
mesh_terms: D003267:Contraception / Q000379:methods* / Q000706:statistics & numerical data; D003625:Data Collection / Q000706:statistics & numerical data*; D003657:Decision Making; D005260:Female; D005602:France / Q000453:epidemiology; D058005:General Practitioners / Q000706:statistics & numerical data*; D006176:Gynecology / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D010819:Physician's Role; D010817:Physician-Patient Relations; D034121:Reproductive Health Services / Q000706:statistics & numerical data; D011795:Surveys and Questionnaires; D014838:Volunteers / Q000706:statistics & numerical data; D000078329:Workforce
keywords: Data collection; Essai randomisé; Methods; Médecins; Méthodologie d’enquête; Physicians; Randomized trial; Santé sexuelle et reproductive; Sexual and reproductive health