Age-specific screening coverage rates were calculated for 18, 36, and 48 months prior to the landmark date of 1 January 2012 (using the 2011 census estimate to provide a denominator for that time point) for comparison with 3-year screening rates based on guideline recommendations (20 (link)–27 (link)). and to parallel estimates of 1 and 3 year coverage reported by the US Centers for Disease Control and Prevention (CDC) (35 ). For the 1 year estimate we included aa 6month ‘grace period’ by showing coverage at 18 months and for the 3 year estimate we included a 12 month ‘grace period” by showing coverage at 48 months. This approach incorporates additional time to accommodate for short delays in annual or triennial screening and provides the most favorable estimate of coverage likely achieved.. Screening intensity was defined as the number of screening tests per woman in the four years from 2008 to 2011. The number of unscreened women was calculated as the difference between the 2008 census population estimate and women with a recorded test during 2008–2011. Data collection and handling methods were unchanged throughout the entire evaluation period. All cervical cytology results were included in this study, including co-testing or cytology alone.
Cytologic results were classified according to the 2001 Bethesda System (36 (link)) as high-grade squamous intraepithelial lesion (HSIL), atypical squamous cells cannot rule out HSIL (ASC-H), atypical glandular cells (AGC), low-grade squamous intraepithelial lesion (LSIL), atypical squamous cells of undetermined significance (ASC-US), and negative for intraepithelial lesion or malignancy. Tests reported as LSIL cannot rule out HSIL (LSIL-H) were categorized as ASC-H, CIN1 as LSIL, and CIN2, CIN2-3, CIN3, carcinoma in situ (CIS), or possible carcinoma as HSIL as previously described.23