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Disease Prevention and Control / Noncommunicable Diseases

Visual Inspection of the Uterine Cervix with Acetic Acid (VIA):
A Critical Review and Selected Articles

Cervical Cancer CD
E-Book (82 pp, PDF)


Visual Inspection of the Uterine Cervix with Acetic Acid (VIA)


The significantly limited impact of cytology-based cervical-cancer screening programs in developing countries is now widely recognized. There are several reasons for these limits, ranging from the nature of participation of women in screening programs to the access and timely completion of treatment when necessary. Much of the discussion on how to improve the effectiveness of screening programs has been centered on analysis of the sensitivity and specificity of screening tests. As a result, new potential screening tests are being proposed, among them visual inspection with acetic acid, which is quite appealing for low-resource settings.

In this publication, we review the available evidence which speaks to the accuracy of visual inspection with acetic acid. The information and findings provided are directed to health professionals and managers of health services as an aid in the decision-making process. As with any new technology, there must be a process of evaluation for this screening method. Ideally, evidence from randomized trials would provide the basis for policy changes. In such trials, women are randomly assigned to be screened with either VIA or another method, and then both groups are followed up and compared. Currently, at least two studies of this nature are ongoing. In the meantime, evidence from cross-sectional studies seems to point out that VIA may be equally or more sensitive than cytology; this would signify a reduction in the rate of women with false negative results. The overarching question is how much and what level of evidence is necessary in order to incorporate this technology into public-health programs.

An important factor for consideration is that the results presented in these papers were obtained under research conditions, with meticulous attention to performance of health-care providers and training. In this way, sensitivity and specificity were estimated under the best of circumstances and conditions. By contrast, a 'real-life' screening program entails a much more varied and complex set of circumstances. Therefore, the ultimate accuracy of the test must be evaluated under conditions that are less than ideal-in other words, conditions that fit the various realities of developing countries. This is important because in the end the feasibility and appropriateness of implementing VIA programs may not depend on the test itself but on the programmatic conditions surrounding the test.

No comprehensive consideration of costs is made throughout the studies contained in this report, but several of the papers assume that the cost must be relatively low since VIA relies on trained human resources and low-cost materials, such as vinegar, etc. It should be noted, however, that costs may increase through high referral rates which might be required with this test, through the intensive and continuous training that a subjective technique usually requires, and most importantly, through quality control measures that a program must have.

With this report, the Pan American Health Organization, as a member of the Alliance for Cervical Cancer Prevention, intends to encourage and facilitate discussion about this test in developing countries. We hope, especially, that as health professionals consider the evidence in light of their own knowledge of the situation in their respective countries, a more confident assessment of VIA may be made. This document does not constitute a formal recommendation, since important results of new studies will be forthcoming. However, it is important at this preliminary stage to pay attention to the issues of methodology and implementation that merit consideration in the design of public health programs.

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