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PDQ Cancer Information Summaries [Internet]. Bethesda (MD): National Cancer Institute (US); 2002-.

Cover of PDQ Cancer Information Summaries

PDQ Cancer Information Summaries [Internet].

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Levels of evidence

Genetics (Prevention) Level of Evidence: 1ai

Randomized, controlled clinical trial with mortality as an endpoint. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Prevention) Level of Evidence: 1aii

Randomized, controlled clinical trial with incidence as an endpoint. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Prevention) Level of Evidence: 1b

Randomized, controlled clinical trial with a generally accepted intermediate endpoint. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Prevention) Level of Evidence: 2ai

Nonrandomized, controlled clinical trial with mortality as an endpoint. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Prevention) Level of Evidence: 2aii

Nonrandomized, controlled clinical trial with incidence as an endpoint. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Prevention) Level of Evidence: 2b

Nonrandomized, controlled clinical trial with a generally accepted intermediate endpoint. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Prevention) Level of Evidence: 3ai

Cohort or case-control studies, preferably from more than one center or research group with mortality as an endpoint. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Prevention) Level of Evidence: 3aii

Cohort or case-control studies, preferably from more than one center or research group with incidence as an endpoint. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Prevention) Level of Evidence: 3b

Cohort or case-control studies, preferably from more than one center or research group with a generally accepted intermediate endpoint. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Prevention) Level of Evidence: 4ai

Ecologic (descriptive) studies with mortality as an endpoint. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Prevention) Level of Evidence: 4aii

Ecologic (descriptive) studies with incidence as an endpoint. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Prevention) Level of Evidence: 4b

Ecologic (descriptive) studies with a generally accepted intermediate endpoint. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Prevention) Level of Evidence: 5

Opinions of respected authorities based on clinical experience or reports of expert committees. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Screening) Level of Evidence: 1

Randomized controlled clinical trial. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Screening) Level of Evidence: 2

Nonrandomized controlled clinical trial. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Screening) Level of Evidence: 3

Cohort or case-control analytic studies, preferably from more than one center or research group. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Screening) Level of Evidence: 4

Multiple time series, with or without an intervention. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Screening) Level of Evidence: 5

Opinion of respected authorities based on clinical experience, descriptive studies, or reports of expert committees. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Treatment) Level of Evidence: 1

Randomized controlled clinical trial. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Treatment) Level of Evidence: 2

Nonrandomized controlled clinical trial. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Treatment) Level of Evidence: 3a

Cohort or case-control analytic studies with total mortality (or overall survival from a defined time) as an endpoint. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Treatment) Level of Evidence: 3b

Cohort or case-control analytic studies with cause-specific mortality (or cause-specific mortality from a defined time) as an endpoint. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Treatment) Level of Evidence: 3c

Cohort or case-control analytic studies with carefully assessed quality of life as an endpoint. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Treatment) Level of Evidence: 3di

Cohort or case-control analytic studies with disease-free survival as an indirect surrogate endpoint. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Treatment) Level of Evidence: 3dii

Cohort or case-control analytic studies with progression-free survival as an indirect surrogate endpoint. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Treatment) Level of Evidence: 3diii

Cohort or case-control analytic studies with tumor response rate as an indirect surrogate endpoint. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Treatment) Level of Evidence: 4

Ecologic, natural history, or descriptive studies. See Levels of Evidence for Cancer Genetics Studies for more information.

Genetics (Treatment) Level of Evidence: 5

Opinions of respected authorities based on clinical experience, descriptive studies, or reports of expert committees. See Levels of Evidence for Cancer Genetics Studies for more information.

Level of evidence 1A

Randomized, controlled clinical trial with total mortality as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 1iA

Randomized, controlled, double-blinded clinical trial with total mortality as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 1iB

Randomized, controlled, double-blinded clinical trial with cause-specific mortality as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 1iC

Randomized, controlled, double-blinded clinical trial with carefully assessed quality of life as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 1iDi

Randomized, controlled, double-blinded clinical trial with event-free survival as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 1iDii

Randomized, controlled, double-blinded clinical trial with disease-free survival as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 1iDiii

Randomized, controlled, double-blinded clinical trial with progression-free survival as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 1iDiv

Randomized, controlled, double-blinded clinical trial with tumor response rate as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 1iiA

Randomized, controlled, nonblinded clinical trial with total mortality as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 1iiB

Randomized, controlled, nonblinded clinical trial with cause-specific mortality as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 1iiC

Randomized, controlled, nonblinded clinical trial with carefully assessed quality of life as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 1iiD

Randomized, controlled, nonblinded clinical trial with indirect surrogates as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 1iiDi

Randomized, controlled, nonblinded clinical trial with event-free survival as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 1iiDii

Randomized, controlled, nonblinded clinical trial with disease-free survival as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 1iiDiii

Randomized, controlled, nonblinded clinical trial with progression-free survival as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 1iiDiv

Randomized, controlled, nonblinded clinical trial with tumor response rate as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 2A

Nonrandomized, controlled clinical trial with total mortality as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 2B

Nonrandomized, controlled clinical trial with cause-specific mortality as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 2C

Nonrandomized, controlled clinical trial with carefully assessed quality of life as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 2Di

Nonrandomized, controlled clinical trial with event-free survival as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 2Dii

Nonrandomized, controlled clinical trial with disease-free survival as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 2Diii

Nonrandomized, controlled clinical trial with progression-free survival as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 2Div

Nonrandomized, controlled clinical trial with tumor response rate as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3i

Case series. Population-based, consecutive series. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3iA

Population-based, consecutive case series with total mortality as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3iB

Population-based, consecutive case series with cause-specific mortality as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3iC

Population-based, consecutive case series with carefully assessed quality of life as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3iDi

Population-based, consecutive case series with event-free survival as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3iDii

Population-based, consecutive case series with disease-free survival as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3iDiii

Population-based, consecutive case series with progression-free survival as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3iDiv

Population-based, consecutive case series with tumor response rate as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3ii

Case series. Consecutive cases (not population-based).See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3iiA

Consecutive case series (not population-based) with total mortality as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3iiB

Consecutive case series (not population-based) with cause-specific mortality as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3iiC

Consecutive case series (not population-based) with carefully assessed quality of life as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3iiD

Consecutive case series (not population-based) with indirect surrogates as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3iiDi

Consecutive case series (not population-based) with event-free survival as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3iiDii

Consecutive case series (not population-based) with disease-free survival as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3iiDiii

Consecutive case series (not population-based) with progression-free survival as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3iiDiv

Consecutive case series (not population-based) with tumor response rate as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3iii

Nonconsecutive case series. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3iiiA

Nonconsecutive case series with total mortality as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3iiiB

Nonconsecutive case series with cause-specific mortality as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3iiiC

Nonconsecutive case series with carefully assessed quality of life as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3iiiD

Nonconsecutive case series with indirect surrogates as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3iiiDi

Nonconsecutive case series with event-free survival as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3iiiDii

Nonconsecutive case series with total disease-free survival as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3iiiDiii

Nonconsecutive case series with progression-free survival as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence 3iiiDiv

Nonconsecutive case series with tumor response rate as an endpoint. See Levels of Evidence for Adult and Pediatric Cancer Treatment Studies (PDQ®) for more information.

Level of evidence I

Prospective, randomized, controlled trials and meta-analyses of prospective, randomized, controlled trials. See Levels of Evidence for Supportive and Palliative Care Studies (PDQ®) for more information.

Level of evidence II

Prospective, nonrandomized, controlled trials; prospective cohort studies; prospective case series; and cross-sectional studies. See Levels of Evidence for Supportive and Palliative Care Studies (PDQ®) for more information.

Level of evidence III

Retrospective studies. See Levels of Evidence for Supportive and Palliative Care Studies (PDQ®) for more information.

Level of evidence IV

Opinions of respected authorities based on clinical experience, consensus statements from expert committees, or authoritative reviews. See Levels of Evidence for Supportive and Palliative Care Studies (PDQ®) for more information.

Bookshelf ID: NBK82220
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