A comparative effectiveness trial of two faecal immunochemical tests for haemoglobin (FIT). Assessment of test performance and adherence in a single round of a population-based screening programme for colorectal cancer

Aim: To compare acceptability and diagnostic accuracy of a recently available faecal immunochemical test (FIT) system (HM-JACKarc) with the FIT routinely used in an established screening programme (OC-Sensor).Design: Randomised controlled trial (ISRCTN20086618) within a population-based colorectal cancer (CRC) screening programme. Subjects eligible for invitation in the Umbria Region (Italy) programme were randomised (ratio 1:1) to be screened using one of the FIT systems.Results: Screening uptake among the 48 888 invitees was the same for both systems among subjects invited in the first round and higher with OC-Sensor than with HM-JACKarc (relative risk (RR): 1.03; 95% CI 1.02 to 1.04) among those invited in subsequent rounds. Positivity rate (PR) was similar with OC-Sensor (6.5%) as with HM-JACKarc (6.2%) among subjects performing their first FIT screening and higher with OC-Sensor (5.6%, RR: 1.25, 95% CI 1.12 to 1.40) than with HM-JACKarc (4.4%) among those screened in previous rounds. Positive predictive value (PPV) (OC-Sensor: 25.9%, HM-JACKarc: 25.6%) and detection rate (DR) (OC-Sensor: 1.40%; HM-JACKarc: 1.42%) for advanced neoplasia (AN: CRC + advanced adenoma) were similar among subjects performing their first FIT screening. The differences in the AN PPV (OC-Sensor: 20.3%, HM-JACKarc: 22.6%) and DR (OC-Sensor: 0.96%, HM-JACKarc: 0.83%) among those screened in previous rounds were not statistically significant. The number needed to scope to detect one AN was 3.9 (95% CI 5.8 to 2.9) and 3.9 (95% CI 5.5 to 2.9) at first and 4.9 (95% CI 5.8 to 4.2) and 4.4 (95% CI 5.3 to 3.7) at subsequent screening, with OC-Sensor and HM-JACKarc, respectively.Conclusions: Our results suggest that acceptability and diagnostic performance of HM-JACKarc and of OC-Sensor systems are similar in a screening setting.Trial registration number: ISRCTN20086618; Results.</p

Geospatial analysis of the influence of family doctor on colorectal cancer screening adherence.

BackgroundDespite the well-recognised relevance of screening in colorectal cancer (CRC) control, adherence to screening is often suboptimal. Improving adherence represents an important public health strategy. We investigated the influence of family doctors (FDs) as determinant of CRC screening adherence by comparing each FDs practice participation probability to that of the residents in the same geographic areas using the whole population geocoded.MethodsWe used multilevel logistic regression model to investigate factors associated with CRC screening adherence, among 333,843 people at their first screening invitation. Standardized Adherence Rates (SAR) by age, gender, and socioeconomic status were calculated comparing FDs practices to the residents in the same geographic areas using geocoded target population.ResultsScreening adherence increased from 41.0% (95% CI, 40.8-41.2) in 2006-2008 to 44.7% (95% CI, 44.5-44.9) in 2011-2012. Males, the most deprived and foreign-born people showed low adherence. FD practices and the percentage of foreign-born people in a practice were significant clustering factors. SAR for 145 (21.4%) FDs practices differed significantly from people living in the same areas. Predicted probabilities of adherence were 31.7% and 49.0% for FDs with low and high adherence, respectively.DiscussionFDs showed a direct and independent effect to the CRC screening adherence of the people living in their practice. FDs with significantly high adherence level could be the key to adherence improvement.ImpactMost deprived individuals and foreigners represent relevant targets for interventions in public health aimed to improve CRC screening adherence

Estimated odds ratios of adherence to CRC screening program for multilevel logistic regression models: Random variation of the intercept for FDs practices and the coefficient for the percentage of foreigners for adherents (Model 1) and for ever-adherents (Model 2).

Estimated odds ratios of adherence to CRC screening program for multilevel logistic regression models: Random variation of the intercept for FDs practices and the coefficient for the percentage of foreigners for adherents (Model 1) and for ever-adherents (Model 2).</p

Risk of screening adherence by category of FD practices.

A. FDs (the markers correspond to the practice baricenter and marker colors to adherence category) plotted against SARs for small triangular areas (about 0.50 km2). B. Top panel: crude adherence rates (left) and (right) by FD practices. Bottom panel: marginal predicted adherence probability for low adherence FDs and high participation FDs and, for comparison, adherence probability for a generic person at average level of covariates. Figure was created by the author Bianconi F. combing the caterpillar, bar plots and maps generate with GeCO-sys an extension of [21].</p

Regional screening adherence mapped as SAR_s by municipality, gender and extreme deprivation categories.

Figure was created by the author Bianconi F. combing the caterpillar plots and maps generate with GeCO-sys an extension of [21].</p

Flow diagram of study population, including a scheme of the geographical analysis used for the FD patients adherence.

Figure was created by the author Bianconi F.</p

Distribution of study variables by adherence to first screening invitation and adherence to any of the three study rounds.

Distribution of study variables by adherence to first screening invitation and adherence to any of the three study rounds.</p