Table 3 shows sensitivity and specificity by the detection method according to histological type, smoking status and rank of screening.
Sensitivity was calculated overall and by gender, age, time since last negative LAT, CRC site, and rank of screening.
Table 4 presents screening test sensitivity, person-years, expected numbers of cancers and sensitivity estimates overall and by time since last LAT, age, gender, location in the large bowel, or rank of screening.
European guidelines for quality assurance in cervical cancer screening ranked indicators of screening effectiveness using a six tier scale.
Although the rank-ordering of screening strategies from most effective to least effective, was two-visit HPV DNA testing, single-visit VIA, and three-visit cytology, differences between these screening approaches were somewhat attenuated at higher vaccination coverage rates.
Table 1 shows the number of screening tests by sex, age group, smoking status and rank of screening tests.
Similarly, lack of statistical significance for sensitivity estimates based on time since last negative test or rank of screening may be due to the small number of events.
Confidence intervals (95% CI) were calculated on the basis of the exact Poisson's distribution, while statistical differences among strata (i.e. gender, age, site, time since last test, rank of screening) were tested by Gaussian approximation of the log likelihood (Clayton and Hills, 1993).
Sensitivity was estimated both overall and by gender, age (50 59 or 60 70) at LAT, time since last negative LAT (first or second year of the interval), cancer location (rectum and rectosigmoid junction: ICDO=154; colon: ICDO=153), and rank of screening (first or subsequent).
The level of evidence was assessed using the US Preventive Services Task Force for ranking evidence for the effectiveness of screening [ 34].
