Visual inspection with acetic acid as a screening test for cervical cancer

Abstract

Visual inspection with acetic acid (VIA) has been extensively investigated and accepted as potential alternative to cytology or Human Papilloma Virus (HPV) screening in limited resource settings. In developing countries, VIA may have several advantages over cytology or HPV screening. The consumables of the test are low-cost and readily available. VIA has potential of achieving large population coverage, as the test can be performed by a wide range of trained health care personnel and requires basic health infrastructure. It is a real-time test and offers logistic advantage of providing treatment for screen positive women during the same visit leading to high treatment coverage. The sensitivity and specificity estimates of VIA generally fall within the range of those reported for cytology and HPV testing. Randomized controlled trials evaluating test performance of VIA have demonstrated reduction in cervical cancer incidence and mortality in study population. The major limitation of VIA is that it is a subjective test and accuracy is dependent on the skill of trained providers. Low specificity and sub-optimal positive predictive value results in unnecessary referrals and/or treatment which can offset the perceived low cost of the test. VIA based screening programs are required to have clearly defined measurable indicators and a framework to identify the program strengths and weaknesses. Quality assurance of VIA is challenging specially because there is limited information on the test performance in multi-provider real programmatic setting. High quality training, periodic refresher courses, expertise of trained providers and close monitoring of performance indicators are required to ensure good quality VIA.