Case-Control Study
An observational study that compares individuals with a specific outcome (cases) to similar individuals without that outcome (controls) to identify factors associated with the outcome. Case-control studies are useful for investigating rare adverse events potentially associated with peptide drug use.
Technical Context
Case-control studies start with the outcome (cases) and look backward for exposures. They are particularly efficient for studying rare events — instead of following thousands of patients to observe rare events prospectively, researchers identify individuals who already experienced the event and compare their treatment history to matched controls. For peptide drug safety, case-control designs have been used to investigate: thyroid cancer in GLP-1 RA users (cases with thyroid cancer matched to controls without), pancreatitis associated with incretin-based therapies, and rare adverse events with specific antimicrobial peptides. Odds ratios (the case-control equivalent of relative risk) quantify the association. Recall bias (cases may recall exposures differently) and selection bias (control selection) are key limitations.