Colorectal CancerNCT01538550
Pilot Study of a National Screening Programme for Bowel Cancer in Norway
A study testing Flexible sigmoidoscopy and iFOBT in people with Colorectal Cancer and Colorectal Adenomas, run by Norwegian Institute of Public Health at 2 sites in Norway.
Trial summary
The Norwegian government has funded a pilot study of a national colorectal cancer screening programme. This implies initiation of a screening pilot in the catchment area for two hospitals in Norway. The target population is average risk men and women at age 50-74 years. Read more about this study
- Who is it for?
- Ages 50 to 74 years
- Conditions the study is for
- Colorectal Cancer, Colorectal Adenomas
- What is being tested?
- Flexible sigmoidoscopy and iFOBT
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 140,000 participants
- Where
- 2 sitesNorway
- Study dates
- Mar 2012to Dec 2034
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 50 to 74 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- men and women
- age 50-74 years
- living in defined geographic areas in South-East Norway (catchment areas for two hospitals)
Who cannot join
- previous colorectal cancer
Trial locations and contacts
2 sites in 1 country.
About this study
Official title: Colorectal Cancer Screening in Norway: Pilot Study of a National Screening Programme With Randomised Comparison of Different Screening Strategies to Provide the Best Possible Service to the Population
The Norwegian government has funded a pilot study of a national colorectal cancer screening programme. This implies initiation of a screening pilot in the catchment area for two hospitals in Norway. The target population is average risk men and women at age 50-74 years. The programme is designed as a comparative effectiveness programme evaluating acceptance and test performance for two screening methods - fecal occult blood testing (FOBT) and flexible sigmoidoscopy (FS). This protocol describes the main methodological issues, necessary resources and the expected effects.
Read the detailed description
There are several candidate screening modalities - fecal occult blood (FOBT), flexible sigmoidoscopy, colonoscopy, CT and MRI colonography and a range of molecular markers. Of these, only FOBT and FS have been subjected to long-term follow-up in randomised trials (RCTs). These two modalities will be tested in a head-to-head comparison by 1:1 randomisation. Previous studies have suggested that the attendance for FS may be lower than for FOBT. However, participation has been shown to decline with repetitive rounds required for FOBT, while infrequent or once-only screening may suffice for FS. A better test performance for FS makes it uncertain which method may be most beneficial in a public health perspective. This is the first time a national screening programme is designed as a platform for comparative effectiveness studies.
The pilot study will be carried out in two hospital catchment areas in South-East Norway - each with a target population of 70,000 men and women at 50-74 years of age - altogether 140,000 individuals to be randomised 1:1 between screening with an immunochemical test for faecal occult blood (iFOBT) biennially or FS once only. The primary endpoint is colorectal mortality reduction after 10 years. Attendance for FS is expected to be 50% and 60% for iFOBT. Expected CRC mortality reduction is 30% (286 CRC deaths) in the FS arm and 15% (143 CRC deaths) in the iFOBT arm (intention-to-treat). In a 1:1 randomisation with 80% statistical power and a significance level of 5% it will require 70,000 individuals in each arm to disclose a statistically significant difference between FS and iFOBT screening in an intention-to-treat model. We expect 5% in the iFOBTs group to test positive and require colonoscopy work-up. A positive FS is defined as 'any advanced neoplasia' (CRC, adenoma >10mm, adenoma with high-grade dysplasia or villous components). A finding of advanced neoplasia is expected in 5% of FS requiring full colonoscopy.
Study entry-date: All individuals were randomized to each of the two groups (iFOBT or sigmoidoscopy) before study start. Because first round screening of the iFOBT arm (70,000 invitees) will be finished in a shorter time frame compared to sigmoidoscopy, invitees in the flexible sigmoidoscopy arm are prone to more relevant time-dependent events between randomization and time of screening actually being offered. Therefore, primary entry-date was defined as day of mailed invitation in both screening groups. This approach means that the mean age at invitation in the sigmoidoscopy screening group will be older than in the iFOBT group, and analyses have to take this age-difference into account. Randomization date was chosen as a secondary study entry date to allow comparative analysis of effects of choosing the two entry date definitions. Sub-studies on lifestyle, psychological reactions comparing participants and control groups not invited to screening from neighbouring municipalities are performed. A randomized sub-study comparing various premedication in work-up colonoscopies is also performed.
Sub-studies
- Changes in modifiable lifestyle factors such as not smoking, normal weight, high level of physical activity may reduce the risk of CRC. Correlation between these factors and endoscopic findings will be assessed. Limited intervention will be tested to improve life style.
- The effect of screening on Psychological factors and the willingness to repeat screening will be assessed
- Creation of a validated Sigmoidoscopy Bowel Preparation scale with subsequent testing of various bowel preparation modalities will be performed.
- RCT with various strategies og analgesia during colonoscopy will be tested to improve patient experience.
- Conditions
- Colorectal Cancer, Colorectal Adenomas
- Being tested
- Flexible sigmoidoscopy, iFOBT
- Keywords
- cancer, colon, rectum, adenoma, screening, iFOBT, flexible sigmoidoscopy, randomized trial
- Medical subject headings
- Colorectal Neoplasms, Neoplasms, Adenoma
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Flexible sigmoidoscopyProcedure or surgery
Also called FlexSig= flexible sigmoidoscopy
Flexible sigmoidoscopy screening is offered once only
iFOBTProcedure or surgery
Also called iFOBT = immunochemical test for fecal occult blood
Biennial screening with iFOBT
| Study group | Role | What they receive |
|---|---|---|
| Flexible sigmoidoscopy | Experimental | 70,000 men and women at age 50-74 years are randomised from the population registry to be invited to have a screening examination using flexible sigmoidoscopy once-only Receives: Procedure: Flexible sigmoidoscopy |
| iFOBT | Experimental | 70,000 men and women at age 50-74 years randomised from the population registry to be invited to have a screening examination biennially using an immunochemical test for fecal occult blood testing (iFOBT). Receives: Procedure: iFOBT |
What is being measured
The primary outcome is the main question the study is designed to answer.
colorectal cancer mortality
colorectal cancer mortality after 10 years of follow-up, possibly extending to 15 years of follow-up
Measured: 10 years
Secondary outcomes (3)
Colorectal cancer incidence
Colorectal cancer incidence after 10 years of follow-up, possibly extending to 15 years of follow-up
Measured: 10 years
Complications and quality assurance
Both screening arms will be subject to continuous registration of complications and quality assurance measures of screening itself and work-up of screening positives
Measured: 4 years
Psychological effects of screening
The level and duration of psychological reactions to screening (anxiety, quality of life) and influence on lifestyle (smoking, physical exercise, dietary habits) will be assessed during the first 4-5 active screening years of the study
Measured: 5 years
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted24 Feb 2012 (estimated)
- Study startMar 2012
- Primary completionDec 2034 (estimated)
- Study completionDec 2034 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (14)Papers the sponsor has linked to this study.
- Other trials for Colorectal CancerStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Screening
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 140,000 participants (actual)
Sponsor and investigators
- Lead sponsor
- Norwegian Institute of Public Health
- Sponsor type
- Other government
- Collaborators
- University of Oslo
- Responsible party
- Sponsor
- Investigators
- Giske Ursin, MD, PhD, Study director, Norwegian Institute of Public HealthKristin Randel, MD, PhD, Principal investigator, Norwegian Institute of Public Health
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT01538550
- Sponsor's protocol ID
- CRCpilotNorway
- Status last verified
- Apr 2026
- First submitted
- 13 Feb 2012
- Last updated
- 14 Apr 2026
- Results posted
- No
- Data monitoring committee
- Yes
Publications
Schult AL, Hoff G, Randel KR, Huppertz-Hauss G, Dalen E, Matapour S, de Lange T, Botteri E. Endoscopist as a key determinant of patient pain: a sigmoidoscopy screening model for unbiased assessment. Scand J Gastroenterol. 2026 Jun;61(6):589-597. doi: 10.1080/00365521.2026.2646941. Epub 2026 Apr 14.
PubMed 41981718Rognstad OB, Botteri E, Hoff G, Bretthauer M, Nguyen HD, Schult AL, Holme O, Randel KR. Use of claims data to identify adverse events after colonoscopy in a randomised colorectal cancer screening trial in Norway: a cross-sectional study. BMJ Open. 2026 Jan 8;16(1):e109883. doi: 10.1136/bmjopen-2025-109883.
PubMed 41506765Rognstad OB, Botteri E, Hoff G, Bretthauer M, Gulichsen E, Frigstad SO, Holme O, Randel KR. Adverse events after colonoscopy in a randomised colorectal cancer screening trial. BMJ Open Gastroenterol. 2024 Oct 7;11(1):e001471. doi: 10.1136/bmjgast-2024-001471.
PubMed 39375173Randel KR, Botteri E, de Lange T, Schult AL, Eskeland SL, El-Safadi B, Norvard ER, Bolstad N, Bretthauer M, Hoff G, Holme O. Performance of Faecal Immunochemical Testing for Colorectal Cancer Screening at Varying Positivity Thresholds. Aliment Pharmacol Ther. 2025 Jan;61(1):122-131. doi: 10.1111/apt.18314. Epub 2024 Oct 7.
PubMed 39373173Bucher-Johannessen C, Senthakumaran T, Avershina E, Birkeland E, Hoff G, Bemanian V, Tunsjo H, Rounge TB. Species-level verification of Phascolarctobacterium association with colorectal cancer. mSystems. 2024 Oct 22;9(10):e0073424. doi: 10.1128/msystems.00734-24. Epub 2024 Sep 17.
PubMed 39287376Randel KR, Schult AL, Botteri E, Nawaz M, Nguyen DH, Holme O, Bretthauer M, Hoff G, de Lange T. Impact of inadequate bowel cleansing in sigmoidoscopy screening. Scand J Gastroenterol. 2024 Aug;59(8):1002-1009. doi: 10.1080/00365521.2024.2364213. Epub 2024 Jun 8.
PubMed 38850200Ribe SG, Botteri E, Loberg M, Randel KR, Kalager M, Nilsen JA, Gulichsen EH, Holme O. Impact of time between faecal immunochemical tests in colorectal cancer screening on screening results: A natural experiment. Int J Cancer. 2023 Apr 1;152(7):1414-1424. doi: 10.1002/ijc.34351. Epub 2022 Nov 21.
PubMed 36346118Schult AL, Botteri E, Hoff G, Holme O, Bretthauer M, Randel KR, Gulichsen EH, El-Safadi B, Barua I, Munck C, Nilsen LR, Svendsen HM, de Lange T. Women require routine opioids to prevent painful colonoscopies: a randomised controlled trial. Scand J Gastroenterol. 2021 Dec;56(12):1480-1489. doi: 10.1080/00365521.2021.1969683. Epub 2021 Sep 17.
PubMed 34534048Kvaerner AS, Birkeland E, Bucher-Johannessen C, Vinberg E, Nordby JI, Kangas H, Bemanian V, Ellonen P, Botteri E, Natvig E, Rognes T, Hovig E, Lyle R, Ambur OH, de Vos WM, Bultman S, Hjartaker A, Landberg R, Song M, Blix HS, Ursin G, Randel KR, de Lange T, Hoff G, Holme O, Berstad P, Rounge TB. The CRCbiome study: a large prospective cohort study examining the role of lifestyle and the gut microbiome in colorectal cancer screening participants. BMC Cancer. 2021 Aug 18;21(1):930. doi: 10.1186/s12885-021-08640-8.
PubMed 34407780Schult AL, Botteri E, Hoff G, Randel KR, Dalen E, Eskeland SL, Holme O, de Lange T. Detection of cancers and advanced adenomas in asymptomatic participants in colorectal cancer screening: a cross-sectional study. BMJ Open. 2021 Jul 1;11(7):e048183. doi: 10.1136/bmjopen-2020-048183.
PubMed 34210732Randel KR, Schult AL, Botteri E, Hoff G, Bretthauer M, Ursin G, Natvig E, Berstad P, Jorgensen A, Sandvei PK, Olsen ME, Frigstad SO, Darre-Naess O, Norvard ER, Bolstad N, Korner H, Wibe A, Wensaas KA, de Lange T, Holme O. Colorectal Cancer Screening With Repeated Fecal Immunochemical Test Versus Sigmoidoscopy: Baseline Results From a Randomized Trial. Gastroenterology. 2021 Mar;160(4):1085-1096.e5. doi: 10.1053/j.gastro.2020.11.037. Epub 2020 Nov 21.
PubMed 33227280Randel KR, Botteri E, Romstad KMK, Frigstad SO, Bretthauer M, Hoff G, de Lange T, Holme O. Effects of Oral Anticoagulants and Aspirin on Performance of Fecal Immunochemical Tests in Colorectal Cancer Screening. Gastroenterology. 2019 May;156(6):1642-1649.e1. doi: 10.1053/j.gastro.2019.01.040. Epub 2019 Jan 25.
PubMed 30689972Kirkoen B, Berstad P, Botteri E, Dalen E, Nilsen JA, Hoff G, de Lange T, Bernklev T. Acceptability of two colorectal cancer screening tests: pain as a key determinant in sigmoidoscopy. Endoscopy. 2017 Nov;49(11):1075-1086. doi: 10.1055/s-0043-117400. Epub 2017 Sep 22.
PubMed 28938500Kirkoen B, Berstad P, Botteri E, Avitsland TL, Ossum AM, de Lange T, Hoff G, Bernklev T. Do no harm: no psychological harm from colorectal cancer screening. Br J Cancer. 2016 Mar 1;114(5):497-504. doi: 10.1038/bjc.2016.14. Epub 2016 Feb 11.
PubMed 26867161
Study at a glance
From the registry record, last updated by the sponsor on 14 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Colorectal Cancer Screening in Norway: Pilot Study of a National Screening Programme With Randomised Comparison of Different Screening Strategies to Provide the Best Possible Service to the Population
- ClinicalTrials.gov ID
- NCT01538550
- Acronym / sponsor ID
- CRCpilotNorway
- Conditions
- Colorectal Cancer, Colorectal Adenomas
- Keywords
- cancer, colon, rectum, adenoma, screening, iFOBT, flexible sigmoidoscopy, randomized trial
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 140,000 participants (actual)
- Lead sponsor
- Norwegian Institute of Public HealthOther government
- Collaborators
- University of Oslo
- Study start
- Mar 2012 (actual)
- Primary completion
- Dec 2034 (estimated)
- Study completion
- Dec 2034 (estimated)
- First posted
- 24 Feb 2012 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The Norwegian government has funded a pilot study of a national colorectal cancer screening programme. This implies initiation of a screening pilot in the catchment area for two hospitals in Norway. The target population is average risk men and women at age 50-74 years. The programme is designed as a comparative effectiveness programme evaluating acceptance and test performance for two screening methods - fecal occult blood testing (FOBT) and flexible sigmoidoscopy (FS). This protocol describes the main methodological issues, necessary resources and the expected effects.
Detailed description
There are several candidate screening modalities - fecal occult blood (FOBT), flexible sigmoidoscopy, colonoscopy, CT and MRI colonography and a range of molecular markers. Of these, only FOBT and FS have been subjected to long-term follow-up in randomised trials (RCTs). These two modalities will be tested in a head-to-head comparison by 1:1 randomisation. Previous studies have suggested that the attendance for FS may be lower than for FOBT. However, participation has been shown to decline with repetitive rounds required for FOBT, while infrequent or once-only screening may suffice for FS. A better test performance for FS makes it uncertain which method may be most beneficial in a public health perspective. This is the first time a national screening programme is designed as a platform for comparative effectiveness studies.
The pilot study will be carried out in two hospital catchment areas in South-East Norway - each with a target population of 70,000 men and women at 50-74 years of age - altogether 140,000 individuals to be randomised 1:1 between screening with an immunochemical test for faecal occult blood (iFOBT) biennially or FS once only. The primary endpoint is colorectal mortality reduction after 10 years. Attendance for FS is expected to be 50% and 60% for iFOBT. Expected CRC mortality reduction is 30% (286 CRC deaths) in the FS arm and 15% (143 CRC deaths) in the iFOBT arm (intention-to-treat). In a 1:1 randomisation with 80% statistical power and a significance level of 5% it will require 70,000 individuals in each arm to disclose a statistically significant difference between FS and iFOBT screening in an intention-to-treat model. We expect 5% in the iFOBTs group to test positive and require colonoscopy work-up. A positive FS is defined as 'any advanced neoplasia' (CRC, adenoma >10mm, adenoma with high-grade dysplasia or villous components). A finding of advanced neoplasia is expected in 5% of FS requiring full colonoscopy.
Study entry-date: All individuals were randomized to each of the two groups (iFOBT or sigmoidoscopy) before study start. Because first round screening of the iFOBT arm (70,000 invitees) will be finished in a shorter time frame compared to sigmoidoscopy, invitees in the flexible sigmoidoscopy arm are prone to more relevant time-dependent events between randomization and time of screening actually being offered. Therefore, primary entry-date was defined as day of mailed invitation in both screening groups. This approach means that the mean age at invitation in the sigmoidoscopy screening group will be older than in the iFOBT group, and analyses have to take this age-difference into account. Randomization date was chosen as a secondary study entry date to allow comparative analysis of effects of choosing the two entry date definitions. Sub-studies on lifestyle, psychological reactions comparing participants and control groups not invited to screening from neighbouring municipalities are performed. A randomized sub-study comparing various premedication in work-up colonoscopies is also performed.
Sub-studies
- Changes in modifiable lifestyle factors such as not smoking, normal weight, high level of physical activity may reduce the risk of CRC. Correlation between these factors and endoscopic findings will be assessed. Limited intervention will be tested to improve life style.
- The effect of screening on Psychological factors and the willingness to repeat screening will be assessed
- Creation of a validated Sigmoidoscopy Bowel Preparation scale with subsequent testing of various bowel preparation modalities will be performed.
- RCT with various strategies og analgesia during colonoscopy will be tested to improve patient experience.
Study design
- Primary purpose
- Screening
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Flexible sigmoidoscopy | Experimental | Procedure: Flexible sigmoidoscopy70,000 men and women at age 50-74 years are randomised from the population registry to be invited to have a screening examination using flexible sigmoidoscopy once-only |
| iFOBT | Experimental | Procedure: iFOBT70,000 men and women at age 50-74 years randomised from the population registry to be invited to have a screening examination biennially using an immunochemical test for fecal occult blood testing (iFOBT). |
Who may qualify
- Ages
- 50 to 74 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- men and women
- age 50-74 years
- living in defined geographic areas in South-East Norway (catchment areas for two hospitals)
Key exclusion criteria (1 listed)
- previous colorectal cancer
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Flexible sigmoidoscopyAlso: FlexSig= flexible sigmoidoscopyFlexible sigmoidoscopy screening is offered once only | Procedure or surgery | Flexible sigmoidoscopy |
| iFOBTAlso: iFOBT = immunochemical test for fecal occult bloodBiennial screening with iFOBT | Procedure or surgery | iFOBT |
Primary outcome
colorectal cancer mortality
Time frame: 10 years
colorectal cancer mortality after 10 years of follow-up, possibly extending to 15 years of follow-up
3 secondary outcomes
Colorectal cancer incidence
Time frame: 10 years
Complications and quality assurance
Time frame: 4 years
Psychological effects of screening
Time frame: 5 years
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 14 Apr 2026.
- Derived from this study: PubMed 41981718Schult AL, Hoff G, Randel KR, Huppertz-Hauss G, Dalen E, Matapour S, de Lange T, Botteri E. Endoscopist as a key determinant of patient pain: a sigmoidoscopy screening model for unbiased assessment. Scand J Gastroenterol. 2026 Jun;61(6):589-597. doi: 10.1080/00365521.2026.2646941. Epub 2026 Apr 14.
- Derived from this study: PubMed 41506765Rognstad OB, Botteri E, Hoff G, Bretthauer M, Nguyen HD, Schult AL, Holme O, Randel KR. Use of claims data to identify adverse events after colonoscopy in a randomised colorectal cancer screening trial in Norway: a cross-sectional study. BMJ Open. 2026 Jan 8;16(1):e109883. doi: 10.1136/bmjopen-2025-109883.
- Derived from this study: PubMed 39375173Rognstad OB, Botteri E, Hoff G, Bretthauer M, Gulichsen E, Frigstad SO, Holme O, Randel KR. Adverse events after colonoscopy in a randomised colorectal cancer screening trial. BMJ Open Gastroenterol. 2024 Oct 7;11(1):e001471. doi: 10.1136/bmjgast-2024-001471.
- Derived from this study: PubMed 39373173Randel KR, Botteri E, de Lange T, Schult AL, Eskeland SL, El-Safadi B, Norvard ER, Bolstad N, Bretthauer M, Hoff G, Holme O. Performance of Faecal Immunochemical Testing for Colorectal Cancer Screening at Varying Positivity Thresholds. Aliment Pharmacol Ther. 2025 Jan;61(1):122-131. doi: 10.1111/apt.18314. Epub 2024 Oct 7.
- Derived from this study: PubMed 39287376Bucher-Johannessen C, Senthakumaran T, Avershina E, Birkeland E, Hoff G, Bemanian V, Tunsjo H, Rounge TB. Species-level verification of Phascolarctobacterium association with colorectal cancer. mSystems. 2024 Oct 22;9(10):e0073424. doi: 10.1128/msystems.00734-24. Epub 2024 Sep 17.
- Derived from this study: PubMed 38850200Randel KR, Schult AL, Botteri E, Nawaz M, Nguyen DH, Holme O, Bretthauer M, Hoff G, de Lange T. Impact of inadequate bowel cleansing in sigmoidoscopy screening. Scand J Gastroenterol. 2024 Aug;59(8):1002-1009. doi: 10.1080/00365521.2024.2364213. Epub 2024 Jun 8.
- Derived from this study: PubMed 36346118Ribe SG, Botteri E, Loberg M, Randel KR, Kalager M, Nilsen JA, Gulichsen EH, Holme O. Impact of time between faecal immunochemical tests in colorectal cancer screening on screening results: A natural experiment. Int J Cancer. 2023 Apr 1;152(7):1414-1424. doi: 10.1002/ijc.34351. Epub 2022 Nov 21.
- Derived from this study: PubMed 34534048Schult AL, Botteri E, Hoff G, Holme O, Bretthauer M, Randel KR, Gulichsen EH, El-Safadi B, Barua I, Munck C, Nilsen LR, Svendsen HM, de Lange T. Women require routine opioids to prevent painful colonoscopies: a randomised controlled trial. Scand J Gastroenterol. 2021 Dec;56(12):1480-1489. doi: 10.1080/00365521.2021.1969683. Epub 2021 Sep 17.
- Derived from this study: PubMed 34407780Kvaerner AS, Birkeland E, Bucher-Johannessen C, Vinberg E, Nordby JI, Kangas H, Bemanian V, Ellonen P, Botteri E, Natvig E, Rognes T, Hovig E, Lyle R, Ambur OH, de Vos WM, Bultman S, Hjartaker A, Landberg R, Song M, Blix HS, Ursin G, Randel KR, de Lange T, Hoff G, Holme O, Berstad P, Rounge TB. The CRCbiome study: a large prospective cohort study examining the role of lifestyle and the gut microbiome in colorectal cancer screening participants. BMC Cancer. 2021 Aug 18;21(1):930. doi: 10.1186/s12885-021-08640-8.
- Derived from this study: PubMed 34210732Schult AL, Botteri E, Hoff G, Randel KR, Dalen E, Eskeland SL, Holme O, de Lange T. Detection of cancers and advanced adenomas in asymptomatic participants in colorectal cancer screening: a cross-sectional study. BMJ Open. 2021 Jul 1;11(7):e048183. doi: 10.1136/bmjopen-2020-048183.
- Derived from this study: PubMed 33227280Randel KR, Schult AL, Botteri E, Hoff G, Bretthauer M, Ursin G, Natvig E, Berstad P, Jorgensen A, Sandvei PK, Olsen ME, Frigstad SO, Darre-Naess O, Norvard ER, Bolstad N, Korner H, Wibe A, Wensaas KA, de Lange T, Holme O. Colorectal Cancer Screening With Repeated Fecal Immunochemical Test Versus Sigmoidoscopy: Baseline Results From a Randomized Trial. Gastroenterology. 2021 Mar;160(4):1085-1096.e5. doi: 10.1053/j.gastro.2020.11.037. Epub 2020 Nov 21.
- Derived from this study: PubMed 30689972Randel KR, Botteri E, Romstad KMK, Frigstad SO, Bretthauer M, Hoff G, de Lange T, Holme O. Effects of Oral Anticoagulants and Aspirin on Performance of Fecal Immunochemical Tests in Colorectal Cancer Screening. Gastroenterology. 2019 May;156(6):1642-1649.e1. doi: 10.1053/j.gastro.2019.01.040. Epub 2019 Jan 25.
- Web page for the study being translated into EnglishLink provided by the sponsor.
Related trials for Colorectal Cancer
RecruitingObservational study
Evaluation for NCI Surgery Branch Clinical Research Protocols
Synovial Cell Cancer, Melanoma
RecruitingPhase 2
Immunotherapy Using Tumor Infiltrating Lymphocytes for Patients With Metastatic Cancer
Metastatic Colorectal Cancer, Metastatic Pancreatic Cancer
RecruitingObservational study
Myopenia and Mechanisms of Chemotherapy Toxicity in Older Adults With Colorectal Cancer
Colorectal Cancer, Sarcopenia
Active, not recruitingPhase 2
Perioperative Cadonilimab (AK104) in Locally Advanced MSI-H/dMMR Gastric or Gastroesophageal Junction and Colorectal Adenocarcinoma
MSI-H/dMMR Gastric Carcinoma and Colorectal Cancer
Active, not recruitingPhase 3
A Study of Encorafenib Plus Cetuximab With or Without Chemotherapy in People With Previously Untreated Metastatic Colorectal Cancer
Neoplasms
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Giske Ursin, MD, PhD study director
Norwegian Institute of Public Health
Kristin Randel, MD, PhD principal investigator
Norwegian Institute of Public Health
2 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Flexible sigmoidoscopy and iFOBT in people with Colorectal Cancer and Colorectal Adenomas, run by Norwegian Institute of Public Health at 2 sites in Norway.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 14 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in Norway. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
colorectal cancer mortality (time frame: 10 years). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT01538550, which also lists 14 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 14 Apr 2026; AzTrials last refreshed its copy on 6 Nov 2026.