Executive Summary
Visual Inspection as a Means of Primary Testing for Cervical Cancer: Results from a
Large-scale Study in Zimbabwe
Jhpiego Technical Report JHP-05 (December 1999)
Visual inspection of the cervix with acetic acid wash (VIA) is a promising
alternative to cytology for cervical cancer screening in low-resource settings. This cross-sectional study was
designed to establish the test qualities (sensitivity, specificity and predictive value) of VIA when performed by
nurse-midwives in a developing country setting. Over the course of the study, 10,956 women were screened by six
trained nurse-midwives at primary healthcare clinics in Zimbabwe. Two screening tests, VIA and the Papanicolaou
(Pap) smear, were administered, and their performances were compared. Colposcopy, with biopsy as indicated, was
used as the reference standard and both test-positive and test-negative participants were referred for colposcopy.
In Phase II of the study (2,203 women), both the screening and reference tests were performed on virtually everyone,
yielding direct estimates of VIA’s test qualities.
In both Phase I and Phase II, VIA was more sensitive, but less specific than
cytology. Phase II estimates of sensitivity for VIA and cytology were 77% and 44%, respectively. Specificity in
Phase II was 64% for VIA and 91% for cytology. In Phase II, 14% of the women were noted to have abnormal Pap
smears while 24% had an abnormal visual screen (i.e., were test-positive).
Findings from this study confirm that, in some settings, VIA performs comparably if
not better than cytology in detecting cases of true disease.
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