Background and Aims

Colorectal cancer (CRC) screening can reduce CRC incidence and mortality, but measuring screening adherence over time is challenging. We examined adherence using a novel measure characterizing the proportion of time covered (PTC) by screening tests.

Methods

Eligible patients were age 50 to 60 years and followed at a large, safety-net health care system between January 2010 and September 2014. We estimated PTC as the number of days up to date with screening divided by the number of days from cohort entry until study end, CRC diagnosis, or death. We estimated mean and median PTC and used least-significant difference tests to assess differences in adherence by patient characteristics.

Results

Of 18,257 patients, most were non-Hispanic black (40.5%) or Hispanic (34.9%) and/or female (62.4%). Approximately 40% (n = 7559) were never screened during the study period; the remaining 10,698 patients completed 19,105 screening examinations (14,481 fecal immunochemical tests [FITs], 4393 colonoscopies, 94 sigmoidoscopies, and 137 barium enemas). Overall, the mean PTC was 29.1% (95% confidence interval [CI], 28.6%-29.5%). Among those who completed at least one screening test (n = 10,698), the mean PTC was 49.0% (95% CI, 48.5%-49.5%). The most common reasons for non-adherence were lack of repeat FIT and no diagnostic colonoscopy after abnormal results for the FIT. The mean PTC increased with the number of primary care visits (0 visits, 21%; 1 visit, 29%; 2-3 visits, 35%; ≥4 visits, 37%; all P < .05).

Conclusions

PTC provides a reliable estimate of screening adherence, capturing breakdowns in the CRC screening process amenable to intervention. Repeat FIT and diagnostic colonoscopy are important intervention targets that may increase adherence in underserved populations.

中文翻译：

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依从覆盖时间的比例来衡量对大肠癌筛查的依从性。

背景和目标

大肠癌（CRC）筛查可以降低CRC的发生率和死亡率，但是随着时间的推移测量筛查依从性具有挑战性。我们使用一种新颖的方法通过筛选测试来表征遵守时间（PTC）的比例，从而检查了依从性。

方法

符合条件的患者年龄在50至60岁之间，并在2010年1月至2014年9月之间采用大型安全网络卫生保健系统。我们估计PTC为截至筛查的最新天数除以从入组到入组的天数。研究结束，CRC诊断或死亡。我们估计了PTC的中位数和中位数，并使用了最低显着性差异测试来评估患者特征依从性的差异。

结果

在18257例患者中，大多数为非西班牙裔黑人（40.5％）或西班牙裔（34.9％）和/或女性（62.4％）。在研究期间从未筛选过大约40％（n = 7559）；其余10698例患者完成了19105例筛查检查（14481例粪便免疫化学测试[FIT]，4393例结肠镜检查，94例乙状结肠镜检查和137例钡剂灌肠）。总体而言，平均PTC为29.1％（95％置信区间[CI]为28.6％-29.5％）。在完成至少一项筛查测试的患者中（n = 10,698），平均PTC为49.0％（95％CI，48.5％-49.5％）。不坚持治疗的最常见原因是重复FIT的缺乏以及FIT异常结果后没有诊断性结肠镜检查。平均PTC随着基层医疗就诊次数的增加而增加（0次就诊，21％； 1次就诊，29％； 2-3次就诊，35％；≥4次就诊，37％；所有P  <.05）。

结论

PTC提供了对筛查依从性的可靠估计，可以捕获CRC筛查过程中适合干预的故障。重复FIT和诊断性结肠镜检查是重要的干预目标，可能会增加服务不足人群的依从性。