Serum and Plasma Collection: Preanalytical Variables and Standard Operating Procedures in Biomarker Research - Proteomic and Metabolomic Approaches to Biomarker Discovery - page 79

TABLE 2 A Selection of Clinical Laboratory Medicine Organizations and Companies (as of August 2012) Regarding
Preanalytical Variables and SOP S Used in Diagnostic or Clinical Laboratories

URL Topic

http://www.clsi.org Clinical and Laboratory Standards Institute

http://www.cdc.gov/clia/default.aspx Clinical Laboratory Improvement Amendments (CLIA)

http://www.fda.gov/MedicalDevices/Device
RegulationandGuidance/IVDRegulatoryAssistance

FDA guidance on In vitro diagnostics

http://www.cap.org College of American Pathologists

http://www.aacc.org American Association for Clinical Chemistry

http://www.bd.com/vacutainer/referencematerial Product information for one brand of blood collection tube

http://www.gbo.com/en/index_1600.php Product information for one brand of blood collection tube

http://www.kendall-ltp.com Product information for one brand of blood collection tube

order to have appropriate samples available for
new future platforms d“

age group or gender, (b) using cases that are
older (longer storage) than the controls, or
(c) plasma collected in ethylenediaminetetraace-
tic acid (EDTA) for cases and heparin for
controls. It is good practice, even in samples
used for initial discovery in unsupervised tech-
nologies, to have sample sets (groups) with no
differences or only minor differences between
them. Engaging clinical researchers, epidemiolo-
gists, and biostatisticians who are experienced in
handling fundamental comparison problems
in the research design phase will reduce bias in
data sets and improve the likelihood of useful
biomarkers that reproducibly classify diseases
from nondisease states. 5

a one size ts most ”

concept. 8,10

SAMPLE SELECTION
CONSIDERATIONS

first question to answer when starting
a biomarker discovery project is what types
of samples will be studied. 1 In addition to con-
sideration of the source of the specimen within
the human body, there are numerous factors to
consider about the human providing the spec-
imen. Ransohoff and Gourlay, in their discussion
of sources of bias in specimens, suggest that the
most critical step in biomarker validation (and
even in discovery) is the

The

HUMAN BLOOD AND ITS
COMPONENTS

“

fundamental compar-

of samples between groups. 5 Fundamental
comparison argues that investigators review
information available about the specimens and
about the subjects who provided them to deter-
mine whether systematic differences exist prior
to any analytical procedures. Some examples of
problematic preanalytical systematic variables
include: (a) collecting cases from one age group
or gender but having controls from a different

ison ”

Human blood is relatively easy to obtain with
a number of minimally invasive collection
options readily available that are cost effective.
In addition, because blood serves as the body s

primary internal transport system, it contains
signi

'

ect the
conditions of the whole human body. Therefore,

cant amounts of proteins that re