http://repub.eur.nl/res/aut/24125/ List of Publications en http://repub.eur.nl/static-eur/img/logo.png http://repub.eur.nl http://repub.eur.nl/res/pub/40051/ 2013-06-01T00:00:00Z Objective: To evaluate the level of informed decision making in a randomized controlled trial comparing colonoscopy and CT-colonography for colorectal cancer screening. Methods: 8844 citizens aged 50-75 were randomly invited to colonoscopy (. n=. 5924) or CT-colonography (. n=. 2920) screening. All invitees received an information leaflet. Screenees received a questionnaire within 4 weeks before the planned examination, non-screenees 4 weeks after the invitation. A decision was categorized as informed when characterized by sufficient decision-relevant knowledge and consistent with personal attitudes toward participation in screening. Results: Knowledge and attitude items were completed by 1032/1276 colonoscopy screenees (81%), by 698/4648 colonoscopy non-screenees (15%), by 824/982 CT-colonography screenees (84%) and by 192/1938 CT-colonography non-screenees (10%). 1027 colonoscopy screenees (>99%) and 815 CT-colonography screenees (99%) had adequate knowledge; 915 (89%) and 742 (90%) had a positive attitude. 675 non-screenees invited to colonoscopy (97%) and 182 invited to CT-colonography (95%) had adequate knowledge; 344 (49%) and 94 (49%) expressed a negative attitude. Conclusion: A large majority of screenees made an informed decision on participation. Almost half of responding non-screenees, made an uninformed decision, suggesting additional barriers to participation. Practice implications: Efforts to understand the additional barriers will create opportunities to facilitate informed participation to colorectal cancer screening. http://repub.eur.nl/res/pub/37441/ 2012-11-01T00:00:00Z Objective: CT-colonography has been suggested to be less burdensome for primary colorectal cancer (CRC) screening than colonoscopy. To compare the expected and perceived burden of both in a randomised trial. Design: 8844 Dutch citizens aged 50-74 years were randomly invited for CRC screening with colonoscopy (n=5924) or CT-colonography (n=2920). Colonoscopy was performed after full colon lavage, or CT-colonography after limited bowel preparation (non-cathartic). All invitees were asked to complete the expected burden questionnaire before the procedure. All participants were invited to complete the perceived burden questionnaire 14 days later. Mean scores were calculated on 5-point scales. Results: Expected burden: 2111 (36%) colonoscopy and 1199 (41%) CT-colonography invitees completed the expected burden questionnaire. Colonoscopy invitees expected the bowel preparation and screening procedure to be more burdensome than CT-colonography invitees: mean scores 3.0±1.1 vs 2.3±0.9 (p<0.001) and 3.1±1.1 vs 2.2±0.9 (p<0.001). Perceived burden: 1009/1276 (79%) colonoscopy and 801/982 (82%) CT-colonography participants completed the perceived burden questionnaire. The full screening procedure was reported as more burdensome in CT-colonography than in colonoscopy: 1.8±0.9 vs 2.0±0.9 (p<0.001). Drinking the bowel preparation resulted in a higher burden score in colonoscopy (3.0±1.3 vs 1.7±1.0, p<0.001) while related bowel movements were scored more burdensome in CT-colonography (2.0±1.0 vs 2.2±1.1, p<0.001). Most participants would probably or definitely take part in a next screening round: 96% for colonoscopy and 93% for CT-colonography (p=0.99). Conclusion: In a CRC screening programme, colonoscopy invitees expected the screening procedure and bowel preparation to be more burdensome than CT-colonography invitees. In participants, CT-colonography was scored as more burdensome than colonoscopy. Intended participation in a next screening round was comparable. http://repub.eur.nl/res/pub/37207/ 2012-01-01T00:00:00Z Background: Screening for colorectal cancer is widely recommended, but the preferred strategy remains unidentified. We aimed to compare participation and diagnostic yield between screening with colonoscopy and with non-cathartic CT colonography. Methods: Members of the general population, aged 50-75 years, and living in the regions of Amsterdam or Rotterdam, identified via the registries of the regional municipal administration, were randomly allocated (2:1) to be invited for primary screening for colorectal cancer by colonoscopy or by CT colonography. Randomisation was done per household with a minimisation algorithm based on age, sex, and socioeconomic status. Invitations were sent between June 8, 2009, and Aug 16, 2010. Participants assigned to CT colonography who were found to have one or more large lesions (≥10 mm) were offered colonoscopy; those with 6-9 mm lesions were offered surveillance CT colonography. The primary outcome was the participation rate, defined as number of invitees undergoing the examination relative to the total number of invitees. Diagnostic yield was calculated as number of participants with advanced neoplasia relative to the total number of invitees. Invitees and screening centre employees were not masked to allocation. This trial is registered in the Dutch trial register, number NTR1829. Findings: 1276 (22%) of 5924 colonoscopy invitees participated, compared with 982 (34%) of 2920 CT colonography invitees (relative risk [RR] 1·56, 95% CI 1·46-1·68; p<0·0001). Of the participants in the colonoscopy group, 111 (9%) had advanced neoplasia of whom seven (<1%) had a carcinoma. Of CT colonography participants, 84 (9%) were offered colonoscopy, of whom 60 (6%) had advanced neoplasia of whom five (<1%) had a carcinoma; 82 (8%) were offered surveillance. The diagnostic yield for all advanced neoplasia was 8·7 per 100 participants for colonoscopy versus 6·1 per 100 for CT colonography (RR 1·46, 95% CI 1·06-2·03; p=0·02) and 1·9 per 100 invitees for colonoscopy and 2·1 per 100 invitees for CT colonography (RR 0·91, 0·66-2·03; p=0·56). The diagnostic yield for advanced neoplasia of 10 mm or more was 1·5 per 100 invitees for colonoscopy and 2·0 per 100 invitees for CT colonography, respectively (RR 0·74, 95% CI 0·53-1·03; p=0·07). Serious adverse events related to the screening procedure were post-polypectomy bleedings: two in the colonoscopy group and three in the CT colonography group. Interpretation: Participation in colorectal cancer screening with CT colonography was significantly better than with colonoscopy, but colonoscopy identified significantly more advanced neoplasia per 100 participants than did CT colonography. The diagnostic yield for advanced neoplasia per 100 invitees was similar for both strategies, indicating that both techniques can be used for population-based screening for colorectal cancer. Other factors such as cost-effectiveness and perceived burden should be taken into account when deciding which technique is preferable. Funding: Netherlands Organisation for Health Research and Development, Centre for Translational Molecular Medicine, and the Nuts Ohra Foundation. http://repub.eur.nl/res/pub/33534/ 2011-02-01T00:00:00Z Purpose: To determine how many computed tomographic (CT) colonography training studies have to be evaluated by novice readers to obtain an adequate level of competence in polyp detection. Materials and Methods: The study was approved by the Institutional Review Board. Informed consent was obtained from all participants. Six physicians (one radiologist, three radiology residents, two researchers) and three technicians completed a CT colonography training program. Two hundred CT colonographic examinations with colonoscopic verification were selected from a research database, with 100 CT colonographic examinations with at least one polyp 6 mm or larger. After a lecture session and short individual hands-on training, CT colonography training was done individually with immediate feedback of colonoscopy outcome. Per-polyp sensitivity was calculated for four sets of 50 CT colonographic examinations for lesions 6 mm or larger. By using logistic regression analyses, the number of CT colonographic examinations to reach 90% sensitivity for lesions 6 mm or larger was estimated. Reading times were registered. Results: The average per-polyp sensitivity for lesions 6 mm or larger was 76% (207 of 270) in the first set of 50 CT colonographic examinations, 77% (262 of 342) in the second (P = .96 vs first set), 80% (310 of 387) in the third(P = .67 vs first set), and 91% (261 of 288) in the fourth(P = .018). The estimated number of CT colonographic examinations for a sufficient sensitivity was 164. Six of nine readers reached this level of competence within 175 CT colonographic examinations. Reading times decreased significantly from the first to the second set of 50 CT colonographic examinations for six readers. Conclusion: Novice CT colonography readers obtained sensitivity equal to that of experienced readers after practicing on average 164 CT colonographic studies. http://repub.eur.nl/res/pub/20181/ 2010-05-19T00:00:00Z Background: Colorectal cancer (CRC) is the second most prevalent type of cancer in Europe. Early detection and removal of CRC or its precursor lesions by population screening can reduce mortality. Colonoscopy and computed tomography colonography (CT colonography) are highly accurate exams and screening options that examine the entire colon. The success of screening depends on the participation rate. We designed a randomized trial to compare the uptake, yield and costs of direct colonoscopy population screening, using either a telephone consultation or a consultation at the outpatient clinic, versus CT colonography first, with colonoscopy in CT colonography positives.Methods and design: 7,500 persons between 50 and 75 years will be randomly selected from the electronic database of the municipal administration registration and will receive an invitation to participate in either CT colonography (2,500 persons) or colonoscopy (5,000 persons) screening. Those invited for colonoscopy screening will be randomized to a prior consultation either by telephone or a visit at the outpatient clinic. All CT colonography invitees will have a prior consultation by telephone. Invitees are instructed to consult their general practitioner and not to participate in screening if they have symptoms suggestive for CRC. After providing informed consent, participants will be scheduled for the screening procedure. The primary outcome measure of this study is the participation rate. Secondary outcomes are the diagnostic yield, the expected and perceived burden of the screening test, level of informed choice and cost-effectiveness of both screening methods.Discussion: This study will provide further evidence to enable decision making in population screening for colorectal cancer.Trial registration: Dutch trial register: NTR1829.