Studies that assessed the accuracy of VIA or VIA with magnification (VIAM) for the detection of histologically confirmed CIN2 or more advanced cervical lesions against the reference standard of histology or colposcopy followed by biopsy were eligible for inclusion. Studies were excluded if they had missing data or imprecise disease definition or if the authors were unable to provide data to construct a 2x2 table of test performance.
All studies defined a positive VIA result as the presence of acetowhite lesions in the transformation zone near the squamocolumnar junction or the os one minute after the direct application of a 3% to 5% diluted solution of acetic acid. All studies were from low and middle income countries. Screeners consisted of clinicians, health workers, colposcopists, cytotechnicians, nurses and midwifes. Age of the women screened ranged from 14 to 74 years. Screening was conducted in hospitals, primary health centers, field clinics and rural or urban centers.
Two reviewers independently selected studies for inclusion.