title: Offering Self-Sampling to Non-Attendees of Organized Primary HPV Screening: When Do Harms Outweigh the Benefits?
abstract: BACKGROUND
  Human papillomavirus (HPV) self-sampling might be a promising tool to increase effectiveness of primary HPV screening programs when offered to non-attendees. However, effectiveness could decrease if regular attendees "switch" to self-sampling, because self-sampling test characteristics may be inferior. We examined under which conditions the harms would outweigh the benefits.
  
  
  METHODS
  The MISCAN-cervix model was used to estimate quality-adjusted life years (QALY) gained and costs of offering HPV self-sampling to non-attendees. We varied the relative CIN2(+) sensitivity and specificity (self-sampling vs. regular sampling), extra attendance, risk of extra attendees, and the switching percentage.
  
  
  RESULTS
  Without switching, offering self-sampling is (cost-)effective under every studied condition. If the attendance due to self-sampling increases by ≥6 percentage points, higher primary background risk women (unscreened women who will never attend regular screening) attend and the relative CIN2(+) sensitivity and specificity are ≥0.95; it is (cost-)effective to offer self-sampling to non-attendees, even if all regular attendees switch. If the relative sensitivity decreases to 0.90 combined with either a 3 percentage points extra attendance or the absence of higher primary background risk women, QALYs are lost when more than 30% to 20% of the regular attendees switch.
  
  
  CONCLUSIONS
  Offering self-sampling will gain health effects if the relative CIN2(+) sensitivity is ≥0.95, unscreened attendees are recruited, and the total attendance increases by ≥6 percentage points. Otherwise, switching of regular attendees may decrease the total effectiveness of the program.
  
  
  CONCLUSIONS
  Self-sampling needs to be implemented with great care and advantages of office-based sampling need to be emphasized to prevent switching.
authors.affiliation: Department of Public Health, Erasmus MC, University Medical Center, Rotterdam, the Netherlands. k.rozemeijer@erasmusmc.nl.
authors.forename: Kirsten
authors.initials: K
authors.lastname: Rozemeijer
authors.affiliation: Department of Public Health, Erasmus MC, University Medical Center, Rotterdam, the Netherlands.
authors.forename: Inge M C M
authors.initials: IM
authors.lastname: de Kok
authors.affiliation: Department of Public Health, Erasmus MC, University Medical Center, Rotterdam, the Netherlands.
authors.forename: Steffie K
authors.initials: SK
authors.lastname: Naber
authors.affiliation: Department of Pathology, Erasmus MC, University Medical Center, Rotterdam, the Netherlands.
authors.forename: Folkert J
authors.initials: FJ
authors.lastname: van Kemenade
authors.affiliation: Department of Public Health, Erasmus MC, University Medical Center, Rotterdam, the Netherlands.
authors.forename: Corine
authors.initials: C
authors.lastname: Penning
authors.affiliation: Department of Public Health, Erasmus MC, University Medical Center, Rotterdam, the Netherlands. Department of Biostatistics, Erasmus MC, University Medical Center, Rotterdam, the Netherlands.
authors.forename: Joost
authors.initials: J
authors.lastname: van Rosmalen
authors.affiliation: Department of Public Health, Erasmus MC, University Medical Center, Rotterdam, the Netherlands.
authors.forename: Marjolein
authors.initials: M
authors.lastname: van Ballegooijen
mesh_terms: D002584:Cervix Uteri / Q000821:virology; D005260:Female; D006801:Humans; D008403:Mass Screening / Q000379:methods*; D009426:Netherlands; D027383:Papillomaviridae / Q000302:isolation & purification*; D030361:Papillomavirus Infections / Q000175:diagnosis* / Q000821:virology; D011320:Primary Health Care / Q000458:organization & administration; D018570:Risk Assessment; D013048:Specimen Handling / Q000379:methods*; D002583:Uterine Cervical Neoplasms / Q000175:diagnosis* / Q000821:virology; D016387:Women's Health