Table 1.

Proteomic study purposes and design choices

	Proteomic study purpose
	Prediction or classification for clinical utility	Association or classification for biologic insight	Classification for novel subtype discovery
Example study	BMD loss or hip fracture[57]	Osteoclast biology[84]	Colorectal cancer subtypes[85, 86]
Sample source	Human population-at-risk	Human biopsy, animal model, or cell line	Human heterogeneous case mix
Sample type	Easily accessible, like serum or plasma	Biologically relevant, like bone tissue or osteoblasts	Accessible during diagnosis, like through blood sample or biopsy
Analytic goal/approach	Portable marker set to optimize prediction or classification	Sufficient marker set to describe biologic process	Portable marker set to optimally separate clinically meaningful classes
Proteomic technology	Global and targeted	Global	Global and targeted