A comparison of colorectal neoplasia screening tests: a multicentre community‐based study of the impact of consumer choice

Abstract

Objective: International guidelines and local practices for colorectal cancer screening suggest an important role for several different screening tests, and for consumer choice. We aimed to determine whether choice of test improved participation in screening. Design: A randomised comparative study offering one of six screening strategies: faecal occult blood testing (FOBT), FOBT and flexible sigmoidoscopy (FS), computed tomography colonography (CTC), colonoscopy, or one of two groups offered a choice of these strategies (one of which was sent an FOBT kit with the letter of invitation, while the other was required to request an FOBT kit by telephone if that was the test chosen). Setting and participants: 1679 people aged 50–54 or 65–69 years, randomly selected from the electoral roll in metropolitan Perth, Adelaide and Melbourne. Main outcome measures: Participation, yield of advanced colorectal neoplasia (CRN), acceptability and safety. Results: 346 (20.6%) were excluded from screening, mostly for a recent examination (165), symptoms (72) or personal or family history of colorectal neoplasia or cancer (83). 278 of the 1333 eligible (20.9%; 95% CI, 18.7%–23.1%) participated in screening. Participation was similar by age and sex, but lower in Perth than Adelaide (17.1% v 24.2%; P = 0.01). Participation by screening group was: FOBT, 27.4%; FOBT/FS, 13.7% (P < 0.001 compared with FOBT); CTC, 16.3% (P = 0.005); colonoscopy, 17.8% (P = 0.02); or a choice of test 18.6% (“with FOBT kit”; P = 0.03) or 22.7% (“without FOBT kit”; P = 0.3). Yield of advanced CRN was higher in participants screened by colonoscopy than FOBT (7.9% v 0.8%; P = 0.02). All tests were well accepted and no serious complications arose from screening. Conclusion: A choice of screening test did not improve participation. Participation by FOBT was higher than by other tests. Yield of advanced colorectal neoplasia on an intention‐to‐screen basis, determined by test sensitivity and participation, is likely to be a critical determinant of the effectiveness of screening strategies.

Acceptability of alternative technologies compared with faecal immunochemical test and/or colonoscopy in colorectal cancer screening: A systematic review

“…Two RCTs compared uptake of CT colonography and FOBT. 21 , 23 Differences in observed uptake were not significant in Forbes 21 study and in You’s study 23 the trial was stopped early. Segnan’s RCT 26 was the only study that compared FS and colonoscopy uptake.…”

“…Four studies compared screening procedure discomfort between CT colonography and colonoscopy. 20 – 21 , 34 , 38 In two studies, discomfort was significantly higher for CT colonography than colonoscopy (p value<0.001). 34 , 38 In the other two studies, differences in median pain scores were not statistically significant.…”

“… 32 – 40 To assess acceptability, studies compared participants who had completed a screening intervention or a comparator. Eight studies compared CT colonography and colonoscopy, 20 – 24 , 34 – 37 , 38 five studies compared FS and FIT, 25 – 28 , 39 four studies compared FS and colonoscopy, 21 , 26 , 36 – 37 four studies compared blood-based biomarker tests and FIT, 29 – 32 two studies compared colon capsule endoscopy and colonoscopy, 33 , 40 two studies compared CT colonography and FOBT 21 , 23 and one study compared CT colonography and FIT. 24 …”

“…Five RCT studies compared uptake between CT colonography and colonoscopy 20 – 24 ( Figure 2(a) ). In two studies, 20 – 21 differences in observed uptake were not statistically significant. In a third study by You, 23 the trial was stopped early; there was insufficient statistical power to detect relevant differences in uptake.…”

“… 34 , 38 In the other two studies, differences in median pain scores were not statistically significant. 20 – 21 Three studies compared screening procedure discomfort between FS and colonoscopy. 21 , 36 – 37 In two studies, differences in pain scores were not significant.…”