TY - JOUR
T1 - Combining and comparing multiple serial dilution assays of particles in solution
T2 - application to brucellosis in elk of the Greater Yellowstone Ecosystem
AU - Barber, Jarrett J.
AU - Gupta, Pritam
AU - Edwards, William
AU - Ogle, Kiona
AU - Waller, Lance A.
N1 - Funding Information:
The authors wish to thank Jessica Jennings-Gaines and Hally Killionof for compiling the data. The first two authors received partial support from U.S. Department of Agriculture Cooperative State Research, Education, and Extension Service (CSREES) Grant USDACSRE45232BA.
Publisher Copyright:
© 2014, Springer Science+Business Media New York.
PY - 2015/3
Y1 - 2015/3
N2 - The concentration detection threshold (CDT) is the concentration of particles in solution beyond which a (serial dilution) assay detects particle presence. By our account, CDTs typically are not estimated but are fixed at some value. Setting a CDT to zero (d = 0) implies perfect detection, a common assumption, and setting d > 0 gives results that are “denominated” in units of d, i.e., are relative to the choice of d. Using multiple, different serial dilution assays, each with its own CDT, we choose a “reference assay,” to which we assign a fixed CDT value, to obtain relative estimates of the remaining assays’ CDTs and the underlying particle concentration. We present the CDTs as a novel way to account for or to compare different serial dilution assays, “sensitivities”. We apply our methodology to data from four assays of the presence of bacterial (B. abortus) antibodies in the serum of elk in the Greater Yellowstone Ecosystem, where transmission of brucellosis—the disease ensuing from infection—to commercial livestock is managed by the Wyoming Game and Fish Department to avoid the primary symptom of abnormal fetal abortion. Results agree qualitatively with the more traditional notion of sensitivity as the true positive rate.
AB - The concentration detection threshold (CDT) is the concentration of particles in solution beyond which a (serial dilution) assay detects particle presence. By our account, CDTs typically are not estimated but are fixed at some value. Setting a CDT to zero (d = 0) implies perfect detection, a common assumption, and setting d > 0 gives results that are “denominated” in units of d, i.e., are relative to the choice of d. Using multiple, different serial dilution assays, each with its own CDT, we choose a “reference assay,” to which we assign a fixed CDT value, to obtain relative estimates of the remaining assays’ CDTs and the underlying particle concentration. We present the CDTs as a novel way to account for or to compare different serial dilution assays, “sensitivities”. We apply our methodology to data from four assays of the presence of bacterial (B. abortus) antibodies in the serum of elk in the Greater Yellowstone Ecosystem, where transmission of brucellosis—the disease ensuing from infection—to commercial livestock is managed by the Wyoming Game and Fish Department to avoid the primary symptom of abnormal fetal abortion. Results agree qualitatively with the more traditional notion of sensitivity as the true positive rate.
KW - Brucellosis
KW - CDT
KW - Concentration detection threshold
KW - Particle concentration
KW - Sensitivity
KW - Serial dilution assay
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U2 - 10.1007/s10651-014-0292-5
DO - 10.1007/s10651-014-0292-5
M3 - Article
AN - SCOPUS:84939882290
SN - 1352-8505
VL - 22
SP - 161
EP - 177
JO - Environmental and Ecological Statistics
JF - Environmental and Ecological Statistics
IS - 1
ER -