Study protocol: population screening for colorectal cancer by colonoscopy or CT colonography: a randomized controlled trial.
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
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.


CONCLUSIONS
This study will provide further evidence to enable decision making in population screening for colorectal cancer.


BACKGROUND
Dutch trial register: NTR1829.
de Wijkerslooth
Thomas R
TR
Department of Gastroenterology and Hepatology, Academic Medical Centre, Amsterdam, the Netherlands.
de Haan
Margriet C
MC
Stoop
Esther M
EM
Deutekom
Marije
M
Fockens
Paul
P
Bossuyt
Patrick M M
PM
Thomeer
Maarten
M
van Ballegooijen
Marjolein
M
Essink-Bot
Marie-Louise
ML
van Leerdam
Monique E
ME
Kuipers
Ernst J
EJ
Dekker
Evelien
E
Stoker
Jaap
J
D000368:Aged; D023881:Colonography, Computed Tomographic / Q000009:adverse effects / Q000191:economics / Q000706:statistics & numerical data; D003113:Colonoscopy / Q000009:adverse effects / Q000191:economics / Q000706:statistics & numerical data; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D003256:Community Participation; D003362:Cost-Benefit Analysis; D006801:Humans; D008403:Mass Screening / Q000379:methods*; D008875:Middle Aged; D009426:Netherlands; D012017:Referral and Consultation; D012307:Risk Factors