title: Determinants of Cervical Cancer Screening Accuracy for Visual Inspection with Acetic Acid (VIA) and Lugol's Iodine (VILI) Performed by Nurse and Physician.
abstract: BACKGROUND
  Visual inspection with acetic acid (VIA) and Lugol's iodine (VILI) are used to screen women for cervical cancer in low-resource settings. Little is known about correlates of their diagnostic accuracy by healthcare provider. We examined determinants of VIA and VILI screening accuracy by examiner in a cross-sectional screening study of 1528 women aged 30 years or older in a suburb of Kinshasa, Democratic Republic of Congo.
  
  
  METHODS
  We used a logistic regression model for sensitivity and specificity to estimate the diagnostic accuracy of VIA and VILI, independently performed by nurse and physician, as a function of sociodemographic and reproductive health characteristics.
  
  
  RESULTS
  Nurses rated tests as positive more often than physicians (36.3% vs 30.2% for VIA, 26.2% vs 25.2% for VILI). Women's age was the most important determinant of performance. It was inversely associated with sensitivity (nurse's VIA: p<0.001, nurse's VILI: p = 0.018, physician's VIA: p = 0.005, physician's VILI: p = 0.006) but positively associated with specificity (all four combinations: p<0.001). Increasing parity adversely affected sensitivity and specificity, but the effects on sensitivity were significant for nurses only. The screening performance of physician's assessment was significantly better than the nurse's (difference in sensitivity: VIA = 13%, VILI = 16%; difference in specificity: VIA = 6%, VILI = 1%).
  
  
  CONCLUSIONS
  Age and parity influence the performance of visual tests for cervical cancer screening. Proper training of local healthcare providers in the conduct of these tests should take into account these factors for improved performance of VIA and VILI in detecting cervical precancerous lesions among women in limited-resource settings.
authors.affiliation: Department of Epidemiology and Biostatistics, Western University, Hamilton, Ontario, Canada.
authors.forename: Amidu O
authors.initials: AO
authors.lastname: Raifu
authors.affiliation: Division of Cancer Epidemiology, Department of Oncology, McGill University, Montreal, Quebec, Canada.
authors.forename: Mariam
authors.initials: M
authors.lastname: El-Zein
authors.affiliation: Department of Obstetrics & Gynaecology, University of Kinshasa, Kinshasa, Democratic Republic of Congo.
authors.forename: Ghislain
authors.initials: G
authors.lastname: Sangwa-Lugoma
authors.affiliation: Division of Cancer Epidemiology, Department of Oncology, McGill University, Montreal, Quebec, Canada.
authors.forename: Agnihotram
authors.initials: A
authors.lastname: Ramanakumar
authors.affiliation: Department of Clinical Epidemiology & Biostatistics, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Stephen D
authors.initials: SD
authors.lastname: Walter
authors.affiliation: Division of Cancer Epidemiology, Department of Oncology, McGill University, Montreal, Quebec, Canada.
authors.forename: Eduardo L
authors.identifier: http://orcid.org/0000-0002-4409-8084
authors.initials: EL
authors.lastname: Franco
mesh_terms: D019342:Acetic Acid / Q000627:therapeutic use*; D000328:Adult; D015023:Democratic Republic of the Congo; D055088:Early Detection of Cancer / Q000379:methods*; D005260:Female; D006801:Humans; D007454:Iodides / Q000627:therapeutic use*; D008875:Middle Aged; D009726:Nurses / Q000706:statistics & numerical data; D010820:Physicians / Q000706:statistics & numerical data; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D002583:Uterine Cervical Neoplasms / Q000175:diagnosis*; D014626:Vaginal Smears / Q000379:methods*
chemical_list: D007454:Iodides; D019342:Acetic Acid; C010389:Lugol's solution