Table 1Inclusion/exclusion criteria

CategoryInclusion CriteriaExclusion Criteria
Study populationHumans, all races, ethnicities, cultural groups
Asymptomatic for CRC and not at increased risk for CRC OR at increased risk for CRC because of a family history of CRC or polyps, or because of a history of polyps at prior colonoscopy
Studies that exclusively focus on CRC screening for patients with a family history
Patients with diagnosis of any of the following:
  • Genetic diagnosis of FAP or suspected FAP without genetic testing evidence
  • Genetic or clinical diagnosis of HNPCC (also known as Lynch syndrome) or individuals at increased risk of HNPCC
  • Inflammatory bowel disease, chronic ulcerative colitis, or Crohn’s disease
  • Colon and/or rectal cancer
  • Other hereditary polyposis syndromes
Studies that assess whether certain groups are at greater risk for CRC than others (e.g., people with comorbidities such as diabetes, liver transplant)
Study outcomesKQ 2: Factors influencing testing/screening rates only or CRC screening discussions (e.g., predisposing patient and provider characteristics, health system factors, interventions) or quality of CRC screening
KQ 3: Interventions focused on changing appropriate CRC screening rates among a specified population and the rates are presented
KQ 4: Available number of screening providers and related equipment/facilities and support personnel to conduct the tests (nurses, etc.)
KQ 5: Existence and adequacy of systems for monitoring CRC screening, CRC screening discussions, quality of CRC screening
KQ 2: Outcomes of knowledge, risk perception, providers’ attitudes toward testing, and/or their referrals to testing (which include no screening outcome data)
KQ 3: Changes in attitudes, beliefs, or intentions to obtain screening
Other criteria specific to outcomes: Outcomes not directly addressing at least one KQ
Cost-effectiveness, cost/benefit, or cost-utility of CRC screening for both included or excluded procedures

Assessment of whether a procedure (usually two procedures compared to each other) is better at diagnosing/more effective than other procedures (usually retrospective)
Assessment of different risk factors for CRC (e.g., diet in relation to diagnosis of CRC, calcium supplements, women taking hormone replacement therapy) and relation to incidence and/or mortality
Treatment of complications (e.g., perforation)
Treatment of CRC itself
Study geographyUnited StatesAll other countries
Time period for data collection1/1/1998–9/30/2009Data collection began before 1/1/1998
Sigmoidoscopy (or FS)
CTC (or virtual colonoscopy with only CT)
Double Contrast Barium Enema (DCBE)Stool tests:
  • DNA stool
  • gFOBT (including Hemoccult® II and Hemoccult® SENSA®)
Office FOBT (unless described/tested along with one of the included interventions)
  • MRI colonoscopy (or virtual colonoscopy with MRI)
  • Genetic testing
  • Ultrasound
Any other tests, including:
  • Any unapproved tests
  • Included procedures combined with others (CTC with stool tagging, CTC with CAD technology)
  • Carbon dioxide insufflation during colonoscopy
  • Whole colonic imaging
  • Chromoendoscopy
  • PET and/or PET in combination with CTC, etc.
  • Bidirectional endoscopy
  • Laparoscopy with colonoscopy
  • Molecular screening
  • Submucosal injection polypectomy
  • Upper GI scope/gastroscope
Studies examining the use of any of the included tests for the monitoring or assessment of a condition or disorder (e.g., diverticulitis) and therefore not for screening or surveillance of abnormal screenings for CRC Studies reporting on the use of included procedures in the surveillance of CRC
Use of any included procedures to stage cancer (e.g., CTC)
Studies testing the differences in sedation, dyes, and bowel cleansing methods during included procedures
Publication languageEnglishAll other languages
Admissible evidence (study design and other criteria)Original research that provides sufficient detail regarding methods and results to enable use and adjustment of the data and results; relevant outcomes must be able to be abstracted from data presented in the papersEligible study designs:
  • Nonrandomized controlled trials
  • Observation studies—prospective and retrospective cohort studies, case-control studies, and cross-sectional studies
  • Modeling studies
Eligible sample sizes:
  • RCTs: N ≥30
  • Nonrandomized controlled trials: N ≥ 30
  • Observational studies: N ≥ 100
  • Single case reports or small case series
  • Systematic reviews
  • Ecologic studies
  • Historical comparisons
KQ 3: Studies without comparison group (e.g., pre/post only were excluded because they are generally unable to determine whether any changes in outcomes were due to a particular intervention as opposed to secular trends or other changes within a practice or setting)

CAD, computer-aided detection; CRC, colorectal cancer; CT, computed tomography; CTC, computed tomographic colonography; DNA Stool, Deoxyribonucleic acid fecal test; FAP, familial adenomatous polyposis; FIT, fecal immunochemical test; FOBT, fecal occult blood test; FS, flexible sigmoidoscopy; gFOBT, guaiac-based fecal occult blood test; GI, gastrointestinal; FS, flexible sigmoidoscopy; HNPCC, hereditary nonpolyposis colorectal cancer; KQ, key question; MR, magnetic resonance; MRI, magnetic resonance imaging; N, number; PET, positron emission tomography; RCT, randomized controlled trial.

From: 2, Methods

Cover of Enhancing the Use and Quality of Colorectal Cancer Screening
Enhancing the Use and Quality of Colorectal Cancer Screening.
Evidence Reports/Technology Assessments, No. 190.
Holden DJ, Harris R, Porterfield DS, et al.

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