PDQ® Levels of Evidence

PDQ cancer information summaries include level-of-evidence designations to help readers understand the strength of the evidence supporting the use of specific interventions or approaches. Levels of evidence are determined by each PDQ Editorial Board, comprised of experts in cancer and other related specialities.

Levels of Evidence for Adult and Pediatric Cancer Treatment Studies
Information about how to weigh the strength of the evidence obtained in different kinds of cancer treatment studies.

Levels of Evidence for Cancer Screening and Prevention Studies
Information about how to weigh the strength of the evidence obtained in cancer screening and prevention research studies.

Levels of Evidence for Cancer Genetics Studies
Information about how to weigh the strength of the evidence obtained in cancer genetics research studies.

Levels of Evidence for Supportive and Palliative Care Studies
Information about how to weigh the strength of the evidence obtained in supportive and palliative care studies.

Levels of Evidence for Human Studies of Cancer Integrative, Alternative, and Complementary Therapies
Information about how to weigh the strength of the evidence obtained in studies of integrative, alternative, and complementary therapies for cancer.