Table 5. Guidelines for biomarker studies.

Structure	Common guidelines	STARD-specific guidelines	REMARK-specific guidelines
Introduction	Background, objective, and hypothesis
Methods	• Eligibility criteria	• Participant identification methods	• Description of biological material used
	• Participants chosen for the study	• Rationale for reference standard	• Clinical endpoints examined
	• Detailed protocol sufficient to replicate		• List of all candidate variables initially examined
	• Study performer, readers, or assessors blinded to identifying information
	• Data collection methods (retrospective vs prospective)
	• Sample size determination
	• Missing data handling
	• Rationale for cut-offs
Results	• Study flow	• Time interval between index test and reference standard	• Univariable analyses revealing the correlation between the marker and outcome
	• Characteristics of patients	• Adverse events due to the index test or the reference standard	• Confidence intervals from an analysis in which the marker and standard prognostic variables are included
	• Relation of index test (marker) and reference standard (prognosis)		• Results of further investigations
	• Estimation of accuracy and precision (STARD) or confidence intervals (REMARK)
Discussion	• Limitations, implications for practice, and future research		• Interpret the results in the context of the pre-specified hypotheses

STARD = STAndards for Reporting of Diagnostic accuracy studies; REMARK = REporting recommendations for tumor MARKer prognostic studies.