<clinical_study>
  <!-- This xml conforms to an XML Schema at:
    https://clinicaltrials.gov/ct2/html/images/info/public.xsd -->
  <required_header>
    <download_date>ClinicalTrials.gov processed this data on September 20, 2023</download_date>
    <link_text>Link to the current ClinicalTrials.gov record.</link_text>
    <url>https://clinicaltrials.gov/ct2/show/NCT04482452</url>
  </required_header>
  <id_info>
    <org_study_id>2020-00074</org_study_id>
    <nct_id>NCT04482452</nct_id>
  </id_info>
  <brief_title>Percentage Visualized Mucosa as a Marker for the Quality of Colonoscopy</brief_title>
  <official_title>Percentage Visualized Mucosa as a Marker for the Quality of Colonoscopy</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>Insel Gruppe AG, University Hospital Bern</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
  </sponsors>
  <source>Insel Gruppe AG, University Hospital Bern</source>
  <oversight_info>
    <has_dmc>No</has_dmc>
    <is_fda_regulated_drug>No</is_fda_regulated_drug>
    <is_fda_regulated_device>No</is_fda_regulated_device>
  </oversight_info>
  <brief_summary>
    <textblock>
      Primary hypothesis: The percentage of mucosa visualized during the withdrawal of a&#xD;
      colonoscopy with reference to the position in the colon by means of the scope-guide is an&#xD;
      appropriate parameter for assessment of the quality of colonoscopy and correlates with the&#xD;
      probability of the detection of adenomas.&#xD;
&#xD;
      Secondary hypothesis:&#xD;
&#xD;
      The investigators hypothesize that the percentage of visualized mucosa differs according&#xD;
      patient specific parameters (e.g. gender, age, BMI, bowel preparation), procedure specific&#xD;
      parameters (e.g. patient position, device, buscopan, fentanyl, withdrawal time) and&#xD;
      investigator specific parameters (professional experience as resident and consultant).&#xD;
&#xD;
      Study Procedure/Evaluation:&#xD;
&#xD;
      The endoscopic images and scope guide from colonoscopy of 500 patients will be filmed. The&#xD;
      investigators will correlate the detection of at least one adenoma in the cohort of included&#xD;
      patients with the percentage of visualized mucosa during the withdrawal of a colonoscopy.&#xD;
      Additional endpoints concerning the quality of the colonoscopy will be assessed as well.&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      PROJECT OBJECTIVES AND DESIGN 1.1 Hypothesis Primary hypothesis: The percentage of mucosa&#xD;
      visualized during the withdrawal of a colonoscopy with reference to the position in the colon&#xD;
      by means of the scope-guide is an appropriate parameter for assessment of the quality of&#xD;
      colonoscopy and correlates with the probability of the detection of adenomas.&#xD;
&#xD;
      Secondary hypothesis:&#xD;
&#xD;
      The investigators hypothesize that the percentage of visualized mucosa differs according&#xD;
      patient specific parameters (e.g. gender, age, BMI, bowel preparation), procedure specific&#xD;
      parameters (e.g. patient position, device, buscopan, fentanyl, withdrawal time) and&#xD;
      investigator specific parameters (professional experience as resident and consultant).&#xD;
&#xD;
      STUDY DESIGN AND PROCEDURES 2.1 Study Design: The investigators will perform a&#xD;
      non-interventional, single center exploratory study. Only total colonoscopies will be&#xD;
      included. All of the examinations will be performed by board-certified specialists or fellows&#xD;
      in training, supervised by the former. The investigators will enroll only participants who&#xD;
      will have an explicit indication, in other words who will get a colonoscopy anyway.&#xD;
      Therefore, colonoscopies will be conducted for a wide variety of indications including, but&#xD;
      not limited, to CRC screening, CRC/ adenoma surveillance, abdominal symptoms such as pain,&#xD;
      irregular defecation (diarrhea or constipation), gastrointestinal occult or overt bleeding,&#xD;
      family history of polyps or CRC, prior colonic resection, hereditary polyposis syndromes and&#xD;
      inflammatory bowel diseases (IBD). Since the study does not pose any additional risk to the&#xD;
      participants (the only thing which changes for the patient is that the endoscopic images from&#xD;
      colonoscopy and scope guide will be filmed), the enrollment can be done during consultation&#xD;
      hour, at the ward or shortly before a colonoscopy.&#xD;
&#xD;
      2.2 Recruitment, screening and informed consent procedure: Patients will be recruited by the&#xD;
      project team in the Department of Visceral Surgery and Medicine at the Inselspital. The&#xD;
      patient will be provided with information regarding the study. If the patient shows interest,&#xD;
      the investigator will explain the study protocol, answer questions and check inclusion and&#xD;
      exclusion criteria. For this study, no compensatory fee will be paid.&#xD;
&#xD;
      2.3 Study procedures: If the patient agrees to participate in the study and has signed the&#xD;
      informed consent the colonoscopy will be performed in the usual setting and using general&#xD;
      safety measures. The endoscopist will start filming all the phases of the colonoscopy and the&#xD;
      position of the scope-guide simultaneously. Both films will be uploaded to the local server&#xD;
      and then cut and analyzed with the help of iMovie. The only study procedure specific for the&#xD;
      study is the filming and no other study specific measures will be taken.&#xD;
&#xD;
      Basic parameters of patient history and colonoscopy procedure will be recorded (compare CRF).&#xD;
      As always, any findings of the colonoscopy will be reported to the participant/ patient after&#xD;
      the procedure.&#xD;
&#xD;
      2.4 Withdrawal and discontinuation: If an individual withdraws informed consent after the&#xD;
      colonoscopy or during the analysis of the data, he/she will be withdrawn from the project.&#xD;
      All videos will be anonymized. In case of withdrawal, patient data and videos will not be&#xD;
      considered for study purposes and will be deleted completely.&#xD;
&#xD;
      STATISTICS AND METHODOLOGY 3.1 Evaluation of Videos: All videos will be anonymized. Then the&#xD;
      percentage of visible mucosa and lumen during withdrawal will be determined in each video.&#xD;
      The scope-guide will allow to correlate the images with the position of the colonoscope&#xD;
      within the colon. The investigators will record the amount of time spend in colon segments&#xD;
      such as the cecum, ascending colon, right flexure, right transverse colon, left transverse&#xD;
      colon, left flexure, descending colon, sigma and rectum. For each of these segments, the&#xD;
      investigators will record the amount of time with good mucosa visibility and poor mucosa&#xD;
      visibility.&#xD;
&#xD;
      In addition to manual analysis, computer-aided analysis and artificial intelligence methods&#xD;
      will be developed to assist the evaluation of the videos. The development of computer-aided&#xD;
      methods consists of two phases. In the first phase, frames in the video will be extracted as&#xD;
      individual images. Experienced physicians will be assigned to annotate the images. The&#xD;
      position of the scope-guide will be extracted for the annotation. Then a classifier based on&#xD;
      deep neural network will be trained on these annotated images. The percentage of visible&#xD;
      mucosa and lumen during withdrawal will be determined in each video based on the&#xD;
      classification results of each individual frame. The classification according to the&#xD;
      scope-guide will allow to correlate the images with the position of the colonoscope within&#xD;
      the colon. The amount of time spending in colon segments such as the cecum, ascending colon,&#xD;
      right flexure, right transverse colon, left transverse colon, left flexure, descending colon,&#xD;
      sigma and rectum will be determined based on deep learning prediction results. Each frame&#xD;
      will be classified to good mucosa visibility and poor mucosa visibility and the amount of&#xD;
      time with good mucosa visibility and poor mucosa visibility of each of the segments will be&#xD;
      determined accordingly. In the second phase, videos will be analysed directly with deep&#xD;
      learning methods and the consistency between the frames will be explored during the analysis&#xD;
      to improve the accuracy.&#xD;
&#xD;
      The investigators will also analyse advancements of the endoscope from the anus to the cecum.&#xD;
      To this end, the time until each of the segments is reached will be recorded as well as all&#xD;
      loops which have formed within the colon.&#xD;
&#xD;
      3.2 Statistical analysis plan 3.2.1. Statistical evaluation of the primary endpoint For&#xD;
      evaluation of the primary endpoint (adenoma detection rate as a function of mucosa&#xD;
      visibility) the investigators will rank all investigations regarding mucosa visibility and&#xD;
      will divide the study population in 50% individuals with the best mucosa visibility and&#xD;
      compare this number to the 50% of individuals with the worst mucosa visibility. They will&#xD;
      compare the fraction of individuals with at least 1 detected adenoma to individuals without a&#xD;
      detected adenoma (Fisher exact test). They will subsequently use multivariate logistic&#xD;
      regression to correct for confounders (age, gender, family history of CRC, personal history&#xD;
      of adenomas, advanced adenomas, carcinomas, BMI and bowel preparation).&#xD;
&#xD;
      3.2.2. Power analysis Our study is exploratory and no proper power analysis is possible. To&#xD;
      provide an estimation the investigators assume that the effect of poor vs. good mucosa&#xD;
      visibility will be as good as the effect of one of a number of technical devices recently&#xD;
      tested in clinical studies to improve adenoma detection during colonoscopy. Such new&#xD;
      technical devices (NTDs) include mucosa caps attached to the tips of the endoscope which&#xD;
      flatten and stretch the mucosa or lenses to improve the field and angle of view. In a recent&#xD;
      meta-analysis, NTDs increased the odds of adenoma detection by 35% (odds ratio 1.35) 25. In a&#xD;
      screening colonoscopy, an adenoma detection rate of at least 20% would be expected 26 (i.e.&#xD;
      50 individuals with at least one adenoma among 250 individuals). In individuals with optimal&#xD;
      mucosa visibility, this number would be 35% higher (i.e. 68 in 250 individuals). According to&#xD;
      the power analysis using G* Power 3.1 27, 419 individuals would be needed to detect such a&#xD;
      difference (i.e. 20% vs. 27% adenoma detection) with a power of 80% at an alpha level of 5%.&#xD;
      The Investigators are aiming to include 500 individuals to account for an estimated 15% of&#xD;
      investigations which could not be evaluated due to incomplete examinations or technical&#xD;
      problems.&#xD;
&#xD;
      3.2.3 Statistical analysis of the secondary endpoints For the secondary outcomes, observed&#xD;
      effects and interactions will be statistically substantiated by parametric and non-parametric&#xD;
      tests and/ or multivariate analyses considering confounders as appropriate. A p-value &lt;0.05&#xD;
      will be considered significant.&#xD;
&#xD;
      3.3 Handling of missing data: The nature of this exploratory study allows for some tolerance&#xD;
      regarding missing data. Patients with incomplete or missing data/videos due to technical&#xD;
      problems will be excluded from the study.&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Unknown status</overall_status>
  <last_known_status>Recruiting</last_known_status>
  <start_date type="Actual">June 8, 2020</start_date>
  <completion_date type="Anticipated">May 19, 2022</completion_date>
  <primary_completion_date type="Anticipated">May 19, 2022</primary_completion_date>
  <study_type>Observational</study_type>
  <has_expanded_access>No</has_expanded_access>
  <study_design_info>
    <observational_model>Cohort</observational_model>
    <time_perspective>Prospective</time_perspective>
  </study_design_info>
  <primary_outcome>
    <measure>Correlation of detection of at least one adenoma with the percentage of visualized mucosa</measure>
    <time_frame>During the procedure</time_frame>
    <description>The investigators will correlate the detection of at least one adenoma in the cohort of included patients with the percentage of visualized mucosa during the withdrawal of a colonoscopy. In the Analysis of the investigators, the ADR will be corrected for confounders (age, gender, family history of CRC, personal history of adenomas, advanced adenomas, carcinomas, BMI and bowel preparation).&#xD;
Mucosa visualization will be defined as the average of the visualized mucosa over all segments of the colon.</description>
  </primary_outcome>
  <secondary_outcome>
    <measure>Correlation of the percentage of visualized mucosa (see above) with the number of polyps, number of adenomas, number of advanced adenomas</measure>
    <time_frame>During the procedure</time_frame>
    <description>Correlation of the percentage of visualized mucosa (see above) with the number of polyps, number of adenomas, number of advanced adenomas</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>In which segment of the colon is the visualization worst</measure>
    <time_frame>During the procedure</time_frame>
    <description>In which segment of the colon is the visualization worst</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Which factors influence the visualization of the colon mucosa</measure>
    <time_frame>During the procedure</time_frame>
    <description>Which factors influence the visualization of the colon mucosa (bowel preparation, withdrawal time, device (colonoscope) selection, water vs. air immersion technique, buscopan, fentanyl, change of position of patient (supine position, lateral position) etc.)</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Change of visualized mucosa during training of a gastroenterology resident (learning curve)</measure>
    <time_frame>During the procedure</time_frame>
    <description>Change of visualized mucosa during training of a gastroenterology resident</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Differences in percentage visualized mucosa between individual board-certified gastroenterologists according to years of professional experience and numbers of previous endoscopies</measure>
    <time_frame>During the procedure</time_frame>
    <description>Differences in percentage visualized mucosa between individual board-certified gastroenterologists according to years of professional experience and numbers of previous endoscopies</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Differences in percentage of visualized mucosa in men vs. women</measure>
    <time_frame>During the procedure</time_frame>
    <description>Differences in percentage of visualized mucosa in men vs. women</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Speed of advancing the endoscope during the first phase of colonoscopy under the conditions mentioned above (bowel preparation, sedation parameters, position, gender, level of professional experience).</measure>
    <time_frame>During the procedure</time_frame>
    <description>Speed of advancing the endoscope during the first phase of colonoscopy</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Loops in the colon (alpha-loop, reverse alpha-loop, N-loop) during advancing the endoscope and the influence of the parameters described under outcome 8)</measure>
    <time_frame>During the procedure</time_frame>
    <description>Loops in the colon (alpha-loop, reverse alpha-loop, N-loop) during advancing the endoscope and the influence of the parameters described under outcome 8)</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>9) The above mentioned primary and secondary end-points will also be assessed using automated image analysis algorithms and artificial intelligence</measure>
    <time_frame>During the procedure</time_frame>
    <description>9) The above mentioned primary and secondary end-points will also be assessed using automated image analysis algorithms and artificial intelligence</description>
  </secondary_outcome>
  <enrollment type="Anticipated">500</enrollment>
  <condition>Colonoscopy</condition>
  <intervention>
    <intervention_type>Procedure</intervention_type>
    <intervention_name>Colonoscopy</intervention_name>
    <description>Diagnostic colonoscopy will be performed</description>
  </intervention>
  <eligibility>
    <study_pop>
      <textblock>
        Individuals undergoing colonoscopy at Dept. of Visceral Surgery and Medicine, Inselspital&#xD;
        Bern&#xD;
      </textblock>
    </study_pop>
    <sampling_method>Non-Probability Sample</sampling_method>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
          -  Signed informed consent.&#xD;
&#xD;
          -  Ability to understand and follow study procedures and understand informed consent.&#xD;
&#xD;
          -  Complete colonoscopy.&#xD;
&#xD;
          -  Age at least 18 years.&#xD;
&#xD;
        Exclusion Criteria:&#xD;
&#xD;
        - Participation in another clinical study interfering with study procedures.&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>18 Years</minimum_age>
    <maximum_age>N/A</maximum_age>
    <healthy_volunteers>Accepts Healthy Volunteers</healthy_volunteers>
  </eligibility>
  <overall_official>
    <last_name>Benjamin Misselwitz, Prof.</last_name>
    <role>Study Director</role>
    <affiliation>Insel Gruppe AG, University Hospital Bern</affiliation>
  </overall_official>
  <overall_contact>
    <last_name>Benjamin Misselwitz, Prof.</last_name>
    <phone>+41 31 632 5719</phone>
    <email>benjamin.misselwitz@insel.ch</email>
  </overall_contact>
  <overall_contact_backup>
    <last_name>Thrasyvoulos Gkrezios, MD</last_name>
    <phone>+41 31 632 5940</phone>
    <email>thrasyvoulos.gkrezios@insel.ch</email>
  </overall_contact_backup>
  <location>
    <facility>
      <name>Inselspital</name>
      <address>
        <city>Bern</city>
        <zip>3010</zip>
        <country>Switzerland</country>
      </address>
    </facility>
    <status>Recruiting</status>
    <contact>
      <last_name>Benjamin Misselwitz, Prof.</last_name>
      <phone>+41316325719</phone>
      <email>benjamin.misselwitz@insel.ch</email>
    </contact>
    <contact_backup>
      <last_name>Thrasyvoulos Gkrezios, MD</last_name>
      <phone>+41316325940</phone>
      <email>thrasyvoulos.gkrezios@insel.ch</email>
    </contact_backup>
  </location>
  <location_countries>
    <country>Switzerland</country>
  </location_countries>
  <link>
    <url>http://www.bfs.admin.ch/bfs/de/home/statistiken/gesundheit/gesundheitszustand/krankheiten/krebs/spezifische.html</url>
    <description>(Swiss) Federal Statistical Office. Cancers in Switzerland.</description>
  </link>
  <reference>
    <citation>Siegel RL, Miller KD, Jemal A. Cancer statistics, 2019. CA Cancer J Clin. 2019 Jan;69(1):7-34. doi: 10.3322/caac.21551. Epub 2019 Jan 8.</citation>
    <PMID>30620402</PMID>
  </reference>
  <reference>
    <citation>Schoen RE, Pinsky PF, Weissfeld JL, Yokochi LA, Church T, Laiyemo AO, Bresalier R, Andriole GL, Buys SS, Crawford ED, Fouad MN, Isaacs C, Johnson CC, Reding DJ, O'Brien B, Carrick DM, Wright P, Riley TL, Purdue MP, Izmirlian G, Kramer BS, Miller AB, Gohagan JK, Prorok PC, Berg CD; PLCO Project Team. Colorectal-cancer incidence and mortality with screening flexible sigmoidoscopy. N Engl J Med. 2012 Jun 21;366(25):2345-57. doi: 10.1056/NEJMoa1114635. Epub 2012 May 21.</citation>
    <PMID>22612596</PMID>
  </reference>
  <reference>
    <citation>Holme O, Loberg M, Kalager M, Bretthauer M, Hernan MA, Aas E, Eide TJ, Skovlund E, Schneede J, Tveit KM, Hoff G. Effect of flexible sigmoidoscopy screening on colorectal cancer incidence and mortality: a randomized clinical trial. JAMA. 2014 Aug 13;312(6):606-15. doi: 10.1001/jama.2014.8266. Erratum In: JAMA. 2014 Sep 3;312(9):964.</citation>
    <PMID>25117129</PMID>
  </reference>
  <reference>
    <citation>Peery AF, Dellon ES, Lund J, Crockett SD, McGowan CE, Bulsiewicz WJ, Gangarosa LM, Thiny MT, Stizenberg K, Morgan DR, Ringel Y, Kim HP, DiBonaventura MD, Carroll CF, Allen JK, Cook SF, Sandler RS, Kappelman MD, Shaheen NJ. Burden of gastrointestinal disease in the United States: 2012 update. Gastroenterology. 2012 Nov;143(5):1179-1187.e3. doi: 10.1053/j.gastro.2012.08.002. Epub 2012 Aug 8.</citation>
    <PMID>22885331</PMID>
  </reference>
  <reference>
    <citation>Sonnenberg A, Amorosi SL, Lacey MJ, Lieberman DA. Patterns of endoscopy in the United States: analysis of data from the Centers for Medicare and Medicaid Services and the National Endoscopic Database. Gastrointest Endosc. 2008 Mar;67(3):489-96. doi: 10.1016/j.gie.2007.08.041. Epub 2008 Jan 7.</citation>
    <PMID>18179793</PMID>
  </reference>
  <reference>
    <citation>Rex DK, Bond JH, Winawer S, Levin TR, Burt RW, Johnson DA, Kirk LM, Litlin S, Lieberman DA, Waye JD, Church J, Marshall JB, Riddell RH; U.S. Multi-Society Task Force on Colorectal Cancer. Quality in the technical performance of colonoscopy and the continuous quality improvement process for colonoscopy: recommendations of the U.S. Multi-Society Task Force on Colorectal Cancer. Am J Gastroenterol. 2002 Jun;97(6):1296-308. doi: 10.1111/j.1572-0241.2002.05812.x. No abstract available.</citation>
    <PMID>12094842</PMID>
  </reference>
  <reference>
    <citation>Rees CJ, Thomas Gibson S, Rutter MD, Baragwanath P, Pullan R, Feeney M, Haslam N; British Society of Gastroenterology, the Joint Advisory Group on GI Endoscopy, the Association of Coloproctology of Great Britain and Ireland. UK key performance indicators and quality assurance standards for colonoscopy. Gut. 2016 Dec;65(12):1923-1929. doi: 10.1136/gutjnl-2016-312044. Epub 2016 Aug 16.</citation>
    <PMID>27531829</PMID>
  </reference>
  <reference>
    <citation>Rex DK, Schoenfeld PS, Cohen J, Pike IM, Adler DG, Fennerty MB, Lieb JG 2nd, Park WG, Rizk MK, Sawhney MS, Shaheen NJ, Wani S, Weinberg DS. Quality indicators for colonoscopy. Am J Gastroenterol. 2015 Jan;110(1):72-90. doi: 10.1038/ajg.2014.385. Epub 2014 Dec 2. No abstract available.</citation>
    <PMID>25448873</PMID>
  </reference>
  <reference>
    <citation>Lieberman D, Ladabaum U, Cruz-Correa M, Ginsburg C, Inadomi JM, Kim LS, Giardiello FM, Wender RC. Screening for Colorectal Cancer and Evolving Issues for Physicians and Patients: A Review. JAMA. 2016 Nov 22;316(20):2135-2145. doi: 10.1001/jama.2016.17418.</citation>
    <PMID>27893135</PMID>
  </reference>
  <reference>
    <citation>Sulz MC, Kroger A, Prakash M, Manser CN, Heinrich H, Misselwitz B. Meta-Analysis of the Effect of Bowel Preparation on Adenoma Detection: Early Adenomas Affected Stronger than Advanced Adenomas. PLoS One. 2016 Jun 3;11(6):e0154149. doi: 10.1371/journal.pone.0154149. eCollection 2016.</citation>
    <PMID>27257916</PMID>
  </reference>
  <reference>
    <citation>Lebwohl B, Kastrinos F, Glick M, Rosenbaum AJ, Wang T, Neugut AI. The impact of suboptimal bowel preparation on adenoma miss rates and the factors associated with early repeat colonoscopy. Gastrointest Endosc. 2011 Jun;73(6):1207-14. doi: 10.1016/j.gie.2011.01.051. Epub 2011 Apr 8.</citation>
    <PMID>21481857</PMID>
  </reference>
  <reference>
    <citation>Calderwood AH, Schroy PC 3rd, Lieberman DA, Logan JR, Zurfluh M, Jacobson BC. Boston Bowel Preparation Scale scores provide a standardized definition of adequate for describing bowel cleanliness. Gastrointest Endosc. 2014 Aug;80(2):269-76. doi: 10.1016/j.gie.2014.01.031. Epub 2014 Mar 12.</citation>
    <PMID>24629422</PMID>
  </reference>
  <reference>
    <citation>Kluge MA, Williams JL, Wu CK, Jacobson BC, Schroy PC 3rd, Lieberman DA, Calderwood AH. Inadequate Boston Bowel Preparation Scale scores predict the risk of missed neoplasia on the next colonoscopy. Gastrointest Endosc. 2018 Mar;87(3):744-751. doi: 10.1016/j.gie.2017.06.012. Epub 2017 Jun 23.</citation>
    <PMID>28648575</PMID>
  </reference>
  <reference>
    <citation>Sawhney MS, Cury MS, Neeman N, Ngo LH, Lewis JM, Chuttani R, Pleskow DK, Aronson MD. Effect of institution-wide policy of colonoscopy withdrawal time &gt; or = 7 minutes on polyp detection. Gastroenterology. 2008 Dec;135(6):1892-8. doi: 10.1053/j.gastro.2008.08.024. Epub 2008 Aug 27.</citation>
    <PMID>18835390</PMID>
  </reference>
  <reference>
    <citation>Kaminski MF, Thomas-Gibson S, Bugajski M, Bretthauer M, Rees CJ, Dekker E, Hoff G, Jover R, Suchanek S, Ferlitsch M, Anderson J, Roesch T, Hultcranz R, Racz I, Kuipers EJ, Garborg K, East JE, Rupinski M, Seip B, Bennett C, Senore C, Minozzi S, Bisschops R, Domagk D, Valori R, Spada C, Hassan C, Dinis-Ribeiro M, Rutter MD. Performance measures for lower gastrointestinal endoscopy: a European Society of Gastrointestinal Endoscopy (ESGE) quality improvement initiative. United European Gastroenterol J. 2017 Apr;5(3):309-334. doi: 10.1177/2050640617700014. Epub 2017 Mar 16.</citation>
    <PMID>28507745</PMID>
  </reference>
  <reference>
    <citation>Szura M, Bucki K, Matyja A, Kulig J. Evaluation of magnetic scope navigation in screening endoscopic examination of colorectal cancer. Surg Endosc. 2012 Mar;26(3):632-8. doi: 10.1007/s00464-011-1930-8. Epub 2011 Sep 30.</citation>
    <PMID>21959687</PMID>
  </reference>
  <reference>
    <citation>Corley DA, Levin TR, Doubeni CA. Adenoma detection rate and risk of colorectal cancer and death. N Engl J Med. 2014 Jun 26;370(26):2541. doi: 10.1056/NEJMc1405329. No abstract available.</citation>
    <PMID>24963577</PMID>
  </reference>
  <reference>
    <citation>Rex DK, Petrini JL, Baron TH, Chak A, Cohen J, Deal SE, Hoffman B, Jacobson BC, Mergener K, Petersen BT, Safdi MA, Faigel DO, Pike IM; ASGE/ACG Taskforce on Quality in Endoscopy. Quality indicators for colonoscopy. Am J Gastroenterol. 2006 Apr;101(4):873-85. doi: 10.1111/j.1572-0241.2006.00673.x. No abstract available.</citation>
    <PMID>16635231</PMID>
  </reference>
  <reference>
    <citation>Kaminski MF, Regula J, Kraszewska E, Polkowski M, Wojciechowska U, Didkowska J, Zwierko M, Rupinski M, Nowacki MP, Butruk E. Quality indicators for colonoscopy and the risk of interval cancer. N Engl J Med. 2010 May 13;362(19):1795-803. doi: 10.1056/NEJMoa0907667.</citation>
    <PMID>20463339</PMID>
  </reference>
  <reference>
    <citation>van Rijn JC, Reitsma JB, Stoker J, Bossuyt PM, van Deventer SJ, Dekker E. Polyp miss rate determined by tandem colonoscopy: a systematic review. Am J Gastroenterol. 2006 Feb;101(2):343-50. doi: 10.1111/j.1572-0241.2006.00390.x.</citation>
    <PMID>16454841</PMID>
  </reference>
  <reference>
    <citation>Bressler B, Paszat LF, Chen Z, Rothwell DM, Vinden C, Rabeneck L. Rates of new or missed colorectal cancers after colonoscopy and their risk factors: a population-based analysis. Gastroenterology. 2007 Jan;132(1):96-102. doi: 10.1053/j.gastro.2006.10.027.</citation>
    <PMID>17241863</PMID>
  </reference>
  <reference>
    <citation>Iwatate M, Kitagawa T, Katayama Y, Tokutomi N, Ban S, Hattori S, Hasuike N, Sano W, Sano Y, Tamano M. Post-colonoscopy colorectal cancer rate in the era of high-definition colonoscopy. World J Gastroenterol. 2017 Nov 14;23(42):7609-7617. doi: 10.3748/wjg.v23.i42.7609.</citation>
    <PMID>29204060</PMID>
  </reference>
  <reference>
    <citation>Castaneda D, Popov VB, Verheyen E, Wander P, Gross SA. New technologies improve adenoma detection rate, adenoma miss rate, and polyp detection rate: a systematic review and meta-analysis. Gastrointest Endosc. 2018 Aug;88(2):209-222.e11. doi: 10.1016/j.gie.2018.03.022. Epub 2018 Apr 1.</citation>
    <PMID>29614263</PMID>
  </reference>
  <reference>
    <citation>Faul F, Erdfelder E, Lang AG, Buchner A. G*Power 3: a flexible statistical power analysis program for the social, behavioral, and biomedical sciences. Behav Res Methods. 2007 May;39(2):175-91. doi: 10.3758/bf03193146.</citation>
    <PMID>17695343</PMID>
  </reference>
  <verification_date>July 2020</verification_date>
  <study_first_submitted>July 7, 2020</study_first_submitted>
  <study_first_submitted_qc>July 17, 2020</study_first_submitted_qc>
  <study_first_posted type="Actual">July 22, 2020</study_first_posted>
  <last_update_submitted>July 17, 2020</last_update_submitted>
  <last_update_submitted_qc>July 17, 2020</last_update_submitted_qc>
  <last_update_posted type="Actual">July 22, 2020</last_update_posted>
  <responsible_party>
    <responsible_party_type>Sponsor</responsible_party_type>
  </responsible_party>
  <patient_data>
    <sharing_ipd>Undecided</sharing_ipd>
  </patient_data>
  <!-- Results have not yet been posted for this study                                          -->
</clinical_study>


download date: ClinicalTrials.gov processed this data on September 20, 2023
link text: Link to the current ClinicalTrials.gov record.
url: https://clinicaltrials.gov/ct2/show/NCT04482452
org study id: 2020-00074
nct id: NCT04482452
lead sponsor: 
has dmc: No
is fda regulated drug: No
is fda regulated device: No
Primary hypothesis: The percentage of mucosa visualized during the withdrawal of a
      colonoscopy with reference to the position in the colon by means of the scope-guide is an
      appropriate parameter for assessment of the quality of colonoscopy and correlates with the
      probability of the detection of adenomas.

      Secondary hypothesis:

      The investigators hypothesize that the percentage of visualized mucosa differs according
      patient specific parameters (e.g. gender, age, BMI, bowel preparation), procedure specific
      parameters (e.g. patient position, device, buscopan, fentanyl, withdrawal time) and
      investigator specific parameters (professional experience as resident and consultant).

      Study Procedure/Evaluation:

      The endoscopic images and scope guide from colonoscopy of 500 patients will be filmed. The
      investigators will correlate the detection of at least one adenoma in the cohort of included
      patients with the percentage of visualized mucosa during the withdrawal of a colonoscopy.
      Additional endpoints concerning the quality of the colonoscopy will be assessed as well.
PROJECT OBJECTIVES AND DESIGN 1.1 Hypothesis Primary hypothesis: The percentage of mucosa
      visualized during the withdrawal of a colonoscopy with reference to the position in the colon
      by means of the scope-guide is an appropriate parameter for assessment of the quality of
      colonoscopy and correlates with the probability of the detection of adenomas.

      Secondary hypothesis:

      The investigators hypothesize that the percentage of visualized mucosa differs according
      patient specific parameters (e.g. gender, age, BMI, bowel preparation), procedure specific
      parameters (e.g. patient position, device, buscopan, fentanyl, withdrawal time) and
      investigator specific parameters (professional experience as resident and consultant).

      STUDY DESIGN AND PROCEDURES 2.1 Study Design: The investigators will perform a
      non-interventional, single center exploratory study. Only total colonoscopies will be
      included. All of the examinations will be performed by board-certified specialists or fellows
      in training, supervised by the former. The investigators will enroll only participants who
      will have an explicit indication, in other words who will get a colonoscopy anyway.
      Therefore, colonoscopies will be conducted for a wide variety of indications including, but
      not limited, to CRC screening, CRC/ adenoma surveillance, abdominal symptoms such as pain,
      irregular defecation (diarrhea or constipation), gastrointestinal occult or overt bleeding,
      family history of polyps or CRC, prior colonic resection, hereditary polyposis syndromes and
      inflammatory bowel diseases (IBD). Since the study does not pose any additional risk to the
      participants (the only thing which changes for the patient is that the endoscopic images from
      colonoscopy and scope guide will be filmed), the enrollment can be done during consultation
      hour, at the ward or shortly before a colonoscopy.

      2.2 Recruitment, screening and informed consent procedure: Patients will be recruited by the
      project team in the Department of Visceral Surgery and Medicine at the Inselspital. The
      patient will be provided with information regarding the study. If the patient shows interest,
      the investigator will explain the study protocol, answer questions and check inclusion and
      exclusion criteria. For this study, no compensatory fee will be paid.

      2.3 Study procedures: If the patient agrees to participate in the study and has signed the
      informed consent the colonoscopy will be performed in the usual setting and using general
      safety measures. The endoscopist will start filming all the phases of the colonoscopy and the
      position of the scope-guide simultaneously. Both films will be uploaded to the local server
      and then cut and analyzed with the help of iMovie. The only study procedure specific for the
      study is the filming and no other study specific measures will be taken.

      Basic parameters of patient history and colonoscopy procedure will be recorded (compare CRF).
      As always, any findings of the colonoscopy will be reported to the participant/ patient after
      the procedure.

      2.4 Withdrawal and discontinuation: If an individual withdraws informed consent after the
      colonoscopy or during the analysis of the data, he/she will be withdrawn from the project.
      All videos will be anonymized. In case of withdrawal, patient data and videos will not be
      considered for study purposes and will be deleted completely.

      STATISTICS AND METHODOLOGY 3.1 Evaluation of Videos: All videos will be anonymized. Then the
      percentage of visible mucosa and lumen during withdrawal will be determined in each video.
      The scope-guide will allow to correlate the images with the position of the colonoscope
      within the colon. The investigators will record the amount of time spend in colon segments
      such as the cecum, ascending colon, right flexure, right transverse colon, left transverse
      colon, left flexure, descending colon, sigma and rectum. For each of these segments, the
      investigators will record the amount of time with good mucosa visibility and poor mucosa
      visibility.

      In addition to manual analysis, computer-aided analysis and artificial intelligence methods
      will be developed to assist the evaluation of the videos. The development of computer-aided
      methods consists of two phases. In the first phase, frames in the video will be extracted as
      individual images. Experienced physicians will be assigned to annotate the images. The
      position of the scope-guide will be extracted for the annotation. Then a classifier based on
      deep neural network will be trained on these annotated images. The percentage of visible
      mucosa and lumen during withdrawal will be determined in each video based on the
      classification results of each individual frame. The classification according to the
      scope-guide will allow to correlate the images with the position of the colonoscope within
      the colon. The amount of time spending in colon segments such as the cecum, ascending colon,
      right flexure, right transverse colon, left transverse colon, left flexure, descending colon,
      sigma and rectum will be determined based on deep learning prediction results. Each frame
      will be classified to good mucosa visibility and poor mucosa visibility and the amount of
      time with good mucosa visibility and poor mucosa visibility of each of the segments will be
      determined accordingly. In the second phase, videos will be analysed directly with deep
      learning methods and the consistency between the frames will be explored during the analysis
      to improve the accuracy.

      The investigators will also analyse advancements of the endoscope from the anus to the cecum.
      To this end, the time until each of the segments is reached will be recorded as well as all
      loops which have formed within the colon.

      3.2 Statistical analysis plan 3.2.1. Statistical evaluation of the primary endpoint For
      evaluation of the primary endpoint (adenoma detection rate as a function of mucosa
      visibility) the investigators will rank all investigations regarding mucosa visibility and
      will divide the study population in 50% individuals with the best mucosa visibility and
      compare this number to the 50% of individuals with the worst mucosa visibility. They will
      compare the fraction of individuals with at least 1 detected adenoma to individuals without a
      detected adenoma (Fisher exact test). They will subsequently use multivariate logistic
      regression to correct for confounders (age, gender, family history of CRC, personal history
      of adenomas, advanced adenomas, carcinomas, BMI and bowel preparation).

      3.2.2. Power analysis Our study is exploratory and no proper power analysis is possible. To
      provide an estimation the investigators assume that the effect of poor vs. good mucosa
      visibility will be as good as the effect of one of a number of technical devices recently
      tested in clinical studies to improve adenoma detection during colonoscopy. Such new
      technical devices (NTDs) include mucosa caps attached to the tips of the endoscope which
      flatten and stretch the mucosa or lenses to improve the field and angle of view. In a recent
      meta-analysis, NTDs increased the odds of adenoma detection by 35% (odds ratio 1.35) 25. In a
      screening colonoscopy, an adenoma detection rate of at least 20% would be expected 26 (i.e.
      50 individuals with at least one adenoma among 250 individuals). In individuals with optimal
      mucosa visibility, this number would be 35% higher (i.e. 68 in 250 individuals). According to
      the power analysis using G* Power 3.1 27, 419 individuals would be needed to detect such a
      difference (i.e. 20% vs. 27% adenoma detection) with a power of 80% at an alpha level of 5%.
      The Investigators are aiming to include 500 individuals to account for an estimated 15% of
      investigations which could not be evaluated due to incomplete examinations or technical
      problems.

      3.2.3 Statistical analysis of the secondary endpoints For the secondary outcomes, observed
      effects and interactions will be statistically substantiated by parametric and non-parametric
      tests and/ or multivariate analyses considering confounders as appropriate. A p-value <0.05
      will be considered significant.

      3.3 Handling of missing data: The nature of this exploratory study allows for some tolerance
      regarding missing data. Patients with incomplete or missing data/videos due to technical
      problems will be excluded from the study.
observational model: Cohort
time perspective: Prospective
measure: Correlation of detection of at least one adenoma with the percentage of visualized mucosa
time frame: During the procedure
description: The investigators will correlate the detection of at least one adenoma in the cohort of included patients with the percentage of visualized mucosa during the withdrawal of a colonoscopy. In the Analysis of the investigators, the ADR will be corrected for confounders (age, gender, family history of CRC, personal history of adenomas, advanced adenomas, carcinomas, BMI and bowel preparation).
Mucosa visualization will be defined as the average of the visualized mucosa over all segments of the colon.
measure: Correlation of the percentage of visualized mucosa (see above) with the number of polyps, number of adenomas, number of advanced adenomas
time frame: During the procedure
description: Correlation of the percentage of visualized mucosa (see above) with the number of polyps, number of adenomas, number of advanced adenomas
measure: In which segment of the colon is the visualization worst
time frame: During the procedure
description: In which segment of the colon is the visualization worst
measure: Which factors influence the visualization of the colon mucosa
time frame: During the procedure
description: Which factors influence the visualization of the colon mucosa (bowel preparation, withdrawal time, device (colonoscope) selection, water vs. air immersion technique, buscopan, fentanyl, change of position of patient (supine position, lateral position) etc.)
measure: Change of visualized mucosa during training of a gastroenterology resident (learning curve)
time frame: During the procedure
description: Change of visualized mucosa during training of a gastroenterology resident
measure: Differences in percentage visualized mucosa between individual board-certified gastroenterologists according to years of professional experience and numbers of previous endoscopies
time frame: During the procedure
description: Differences in percentage visualized mucosa between individual board-certified gastroenterologists according to years of professional experience and numbers of previous endoscopies
measure: Differences in percentage of visualized mucosa in men vs. women
time frame: During the procedure
description: Differences in percentage of visualized mucosa in men vs. women
measure: Speed of advancing the endoscope during the first phase of colonoscopy under the conditions mentioned above (bowel preparation, sedation parameters, position, gender, level of professional experience).
time frame: During the procedure
description: Speed of advancing the endoscope during the first phase of colonoscopy
measure: Loops in the colon (alpha-loop, reverse alpha-loop, N-loop) during advancing the endoscope and the influence of the parameters described under outcome 8)
time frame: During the procedure
description: Loops in the colon (alpha-loop, reverse alpha-loop, N-loop) during advancing the endoscope and the influence of the parameters described under outcome 8)
measure: 9) The above mentioned primary and secondary end-points will also be assessed using automated image analysis algorithms and artificial intelligence
time frame: During the procedure
description: 9) The above mentioned primary and secondary end-points will also be assessed using automated image analysis algorithms and artificial intelligence
intervention type: Procedure
intervention name: Colonoscopy
description: Diagnostic colonoscopy will be performed
study pop: 
sampling method: Non-Probability Sample
criteria: 
gender: All
minimum age: 18 Years
maximum age: N/A
healthy volunteers: Accepts Healthy Volunteers
last name: Benjamin Misselwitz, Prof.
role: Study Director
affiliation: Insel Gruppe AG, University Hospital Bern
last name: Benjamin Misselwitz, Prof.
phone: +41 31 632 5719
email: benjamin.misselwitz@insel.ch
last name: Thrasyvoulos Gkrezios, MD
phone: +41 31 632 5940
email: thrasyvoulos.gkrezios@insel.ch
facility: 
status: Recruiting
contact: 
contact backup: 
country: Switzerland
url: http://www.bfs.admin.ch/bfs/de/home/statistiken/gesundheit/gesundheitszustand/krankheiten/krebs/spezifische.html
description: (Swiss) Federal Statistical Office. Cancers in Switzerland.
citation: Siegel RL, Miller KD, Jemal A. Cancer statistics, 2019. CA Cancer J Clin. 2019 Jan;69(1):7-34. doi: 10.3322/caac.21551. Epub 2019 Jan 8.
PMID: 30620402
citation: Schoen RE, Pinsky PF, Weissfeld JL, Yokochi LA, Church T, Laiyemo AO, Bresalier R, Andriole GL, Buys SS, Crawford ED, Fouad MN, Isaacs C, Johnson CC, Reding DJ, O'Brien B, Carrick DM, Wright P, Riley TL, Purdue MP, Izmirlian G, Kramer BS, Miller AB, Gohagan JK, Prorok PC, Berg CD; PLCO Project Team. Colorectal-cancer incidence and mortality with screening flexible sigmoidoscopy. N Engl J Med. 2012 Jun 21;366(25):2345-57. doi: 10.1056/NEJMoa1114635. Epub 2012 May 21.
PMID: 22612596
citation: Holme O, Loberg M, Kalager M, Bretthauer M, Hernan MA, Aas E, Eide TJ, Skovlund E, Schneede J, Tveit KM, Hoff G. Effect of flexible sigmoidoscopy screening on colorectal cancer incidence and mortality: a randomized clinical trial. JAMA. 2014 Aug 13;312(6):606-15. doi: 10.1001/jama.2014.8266. Erratum In: JAMA. 2014 Sep 3;312(9):964.
PMID: 25117129
citation: Peery AF, Dellon ES, Lund J, Crockett SD, McGowan CE, Bulsiewicz WJ, Gangarosa LM, Thiny MT, Stizenberg K, Morgan DR, Ringel Y, Kim HP, DiBonaventura MD, Carroll CF, Allen JK, Cook SF, Sandler RS, Kappelman MD, Shaheen NJ. Burden of gastrointestinal disease in the United States: 2012 update. Gastroenterology. 2012 Nov;143(5):1179-1187.e3. doi: 10.1053/j.gastro.2012.08.002. Epub 2012 Aug 8.
PMID: 22885331
citation: Sonnenberg A, Amorosi SL, Lacey MJ, Lieberman DA. Patterns of endoscopy in the United States: analysis of data from the Centers for Medicare and Medicaid Services and the National Endoscopic Database. Gastrointest Endosc. 2008 Mar;67(3):489-96. doi: 10.1016/j.gie.2007.08.041. Epub 2008 Jan 7.
PMID: 18179793
citation: Rex DK, Bond JH, Winawer S, Levin TR, Burt RW, Johnson DA, Kirk LM, Litlin S, Lieberman DA, Waye JD, Church J, Marshall JB, Riddell RH; U.S. Multi-Society Task Force on Colorectal Cancer. Quality in the technical performance of colonoscopy and the continuous quality improvement process for colonoscopy: recommendations of the U.S. Multi-Society Task Force on Colorectal Cancer. Am J Gastroenterol. 2002 Jun;97(6):1296-308. doi: 10.1111/j.1572-0241.2002.05812.x. No abstract available.
PMID: 12094842
citation: Rees CJ, Thomas Gibson S, Rutter MD, Baragwanath P, Pullan R, Feeney M, Haslam N; British Society of Gastroenterology, the Joint Advisory Group on GI Endoscopy, the Association of Coloproctology of Great Britain and Ireland. UK key performance indicators and quality assurance standards for colonoscopy. Gut. 2016 Dec;65(12):1923-1929. doi: 10.1136/gutjnl-2016-312044. Epub 2016 Aug 16.
PMID: 27531829
citation: Rex DK, Schoenfeld PS, Cohen J, Pike IM, Adler DG, Fennerty MB, Lieb JG 2nd, Park WG, Rizk MK, Sawhney MS, Shaheen NJ, Wani S, Weinberg DS. Quality indicators for colonoscopy. Am J Gastroenterol. 2015 Jan;110(1):72-90. doi: 10.1038/ajg.2014.385. Epub 2014 Dec 2. No abstract available.
PMID: 25448873
citation: Lieberman D, Ladabaum U, Cruz-Correa M, Ginsburg C, Inadomi JM, Kim LS, Giardiello FM, Wender RC. Screening for Colorectal Cancer and Evolving Issues for Physicians and Patients: A Review. JAMA. 2016 Nov 22;316(20):2135-2145. doi: 10.1001/jama.2016.17418.
PMID: 27893135
citation: Sulz MC, Kroger A, Prakash M, Manser CN, Heinrich H, Misselwitz B. Meta-Analysis of the Effect of Bowel Preparation on Adenoma Detection: Early Adenomas Affected Stronger than Advanced Adenomas. PLoS One. 2016 Jun 3;11(6):e0154149. doi: 10.1371/journal.pone.0154149. eCollection 2016.
PMID: 27257916
citation: Lebwohl B, Kastrinos F, Glick M, Rosenbaum AJ, Wang T, Neugut AI. The impact of suboptimal bowel preparation on adenoma miss rates and the factors associated with early repeat colonoscopy. Gastrointest Endosc. 2011 Jun;73(6):1207-14. doi: 10.1016/j.gie.2011.01.051. Epub 2011 Apr 8.
PMID: 21481857
citation: Calderwood AH, Schroy PC 3rd, Lieberman DA, Logan JR, Zurfluh M, Jacobson BC. Boston Bowel Preparation Scale scores provide a standardized definition of adequate for describing bowel cleanliness. Gastrointest Endosc. 2014 Aug;80(2):269-76. doi: 10.1016/j.gie.2014.01.031. Epub 2014 Mar 12.
PMID: 24629422
citation: Kluge MA, Williams JL, Wu CK, Jacobson BC, Schroy PC 3rd, Lieberman DA, Calderwood AH. Inadequate Boston Bowel Preparation Scale scores predict the risk of missed neoplasia on the next colonoscopy. Gastrointest Endosc. 2018 Mar;87(3):744-751. doi: 10.1016/j.gie.2017.06.012. Epub 2017 Jun 23.
PMID: 28648575
citation: Sawhney MS, Cury MS, Neeman N, Ngo LH, Lewis JM, Chuttani R, Pleskow DK, Aronson MD. Effect of institution-wide policy of colonoscopy withdrawal time > or = 7 minutes on polyp detection. Gastroenterology. 2008 Dec;135(6):1892-8. doi: 10.1053/j.gastro.2008.08.024. Epub 2008 Aug 27.
PMID: 18835390
citation: Kaminski MF, Thomas-Gibson S, Bugajski M, Bretthauer M, Rees CJ, Dekker E, Hoff G, Jover R, Suchanek S, Ferlitsch M, Anderson J, Roesch T, Hultcranz R, Racz I, Kuipers EJ, Garborg K, East JE, Rupinski M, Seip B, Bennett C, Senore C, Minozzi S, Bisschops R, Domagk D, Valori R, Spada C, Hassan C, Dinis-Ribeiro M, Rutter MD. Performance measures for lower gastrointestinal endoscopy: a European Society of Gastrointestinal Endoscopy (ESGE) quality improvement initiative. United European Gastroenterol J. 2017 Apr;5(3):309-334. doi: 10.1177/2050640617700014. Epub 2017 Mar 16.
PMID: 28507745
citation: Szura M, Bucki K, Matyja A, Kulig J. Evaluation of magnetic scope navigation in screening endoscopic examination of colorectal cancer. Surg Endosc. 2012 Mar;26(3):632-8. doi: 10.1007/s00464-011-1930-8. Epub 2011 Sep 30.
PMID: 21959687
citation: Corley DA, Levin TR, Doubeni CA. Adenoma detection rate and risk of colorectal cancer and death. N Engl J Med. 2014 Jun 26;370(26):2541. doi: 10.1056/NEJMc1405329. No abstract available.
PMID: 24963577
citation: Rex DK, Petrini JL, Baron TH, Chak A, Cohen J, Deal SE, Hoffman B, Jacobson BC, Mergener K, Petersen BT, Safdi MA, Faigel DO, Pike IM; ASGE/ACG Taskforce on Quality in Endoscopy. Quality indicators for colonoscopy. Am J Gastroenterol. 2006 Apr;101(4):873-85. doi: 10.1111/j.1572-0241.2006.00673.x. No abstract available.
PMID: 16635231
citation: Kaminski MF, Regula J, Kraszewska E, Polkowski M, Wojciechowska U, Didkowska J, Zwierko M, Rupinski M, Nowacki MP, Butruk E. Quality indicators for colonoscopy and the risk of interval cancer. N Engl J Med. 2010 May 13;362(19):1795-803. doi: 10.1056/NEJMoa0907667.
PMID: 20463339
citation: van Rijn JC, Reitsma JB, Stoker J, Bossuyt PM, van Deventer SJ, Dekker E. Polyp miss rate determined by tandem colonoscopy: a systematic review. Am J Gastroenterol. 2006 Feb;101(2):343-50. doi: 10.1111/j.1572-0241.2006.00390.x.
PMID: 16454841
citation: Bressler B, Paszat LF, Chen Z, Rothwell DM, Vinden C, Rabeneck L. Rates of new or missed colorectal cancers after colonoscopy and their risk factors: a population-based analysis. Gastroenterology. 2007 Jan;132(1):96-102. doi: 10.1053/j.gastro.2006.10.027.
PMID: 17241863
citation: Iwatate M, Kitagawa T, Katayama Y, Tokutomi N, Ban S, Hattori S, Hasuike N, Sano W, Sano Y, Tamano M. Post-colonoscopy colorectal cancer rate in the era of high-definition colonoscopy. World J Gastroenterol. 2017 Nov 14;23(42):7609-7617. doi: 10.3748/wjg.v23.i42.7609.
PMID: 29204060
citation: Castaneda D, Popov VB, Verheyen E, Wander P, Gross SA. New technologies improve adenoma detection rate, adenoma miss rate, and polyp detection rate: a systematic review and meta-analysis. Gastrointest Endosc. 2018 Aug;88(2):209-222.e11. doi: 10.1016/j.gie.2018.03.022. Epub 2018 Apr 1.
PMID: 29614263
citation: Faul F, Erdfelder E, Lang AG, Buchner A. G*Power 3: a flexible statistical power analysis program for the social, behavioral, and biomedical sciences. Behav Res Methods. 2007 May;39(2):175-91. doi: 10.3758/bf03193146.
PMID: 17695343
responsible party type: Sponsor
sharing ipd: Undecided