biostudies-literatureZhang WInnovative Research Group Project of the National Natural Science Foundation of ChinaNational Institutes of Health55https://www.ebi.ac.uk/biostudies/studies/S-EPMC7977501biostudies-literatureUnknown21(1)<h4>Background</h4>Cancer treatment is increasingly dependent on biomarkers for prognostication and treatment selection. Potential biomarkers are frequently evaluated in prospective-retrospective studies in which biomarkers are measured retrospectively on archived specimens after completion of prospective clinical trials. In light of the high costs of some assays, random sampling designs have been proposed that measure biomarkers for a random sub-sample of subjects selected on the basis of observed outcome and possibly other variables. Compared with a standard design that measures biomarkers on all subjects, a random sampling design can be cost-efficient in the sense of reducing the cost of the study substantially while achieving a reasonable level of precision.<h4>Methods</h4>For a biomarBMC medical research methodologyGroup testing can improve the cost-efficiency of prospective-retrospective biomarker studies.PMC797750112001522Zhang WKrushkal JZhang ZLiu AfalseGroup testing can improve the cost-efficiency of prospective-retrospective biomarker studies.<h4>Background</h4>Cancer treatment is increasingly dependent on biomarkers for prognostication and treatment selection. Potential biomarkers are frequently evaluated in prospective-retrospective studies in which biomarkers are measured retrospectively on archived specimens after completion of prospective clinical trials. In light of the high costs of some assays, random sampling designs have been proposed that measure biomarkers for a random sub-sample of subjects selected on the basis of observed outcome and possibly other variables. Compared with a standard design that measures biomarkers on all subjects, a random sampling design can be cost-efficient in the sense of reducing the cost of the study substantially while achieving a reasonable level of precision.<h4>Methods</h4>For a biomar2021-01-01T00:00:00Z2021 Mar2026-04-16T15:03:37.247Z2025-02-19T02:13:41.126ZS-EPMC79775013374089010.1186/s12874-021-01239-4