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. 2013 Dec 24;2013:862514. doi: 10.1155/2013/862514

Table 5.

Prediction/discrimination of impaired fasting glucose and the metabolic syndrome with degree of obesity as defined by dual-energy X-ray absorptiometry (DXA) bioimpedance analysis (BIA), an anthropometry-based estimate of fat mass percentage (FM%-equation) and BMI.

ROC analysesn
Reference method/modela New method/modelb n c Reclassification index, %f IDI, %k Men Women
Casesd Non-casese Netg P nri h Casesi Non-casesj I integr. l P idi m Δ AUCo P p Δ AUC P
Impaired fasting glucose (≥5.6 mmol/L = 100 mg/dL)
DXA BIA InBodyq 164 249 −6% 0.181 −7% 1% −0.5% 0.506 −0.03 0.102 −0.01 0.394
BMI 191 276 −2% 0.727 −4% 2% 0.3% 0.723 −0.04 0.286 −0.02 0.394
Estimater 191 276 −1% 0.771 −4% 2% 0.2% 0.809 −0.03 0.404 −0.01 0.597
BIA InBody BMI 164 249 2% 0.752 1% 0% 0.2% 0.796 −0.01 0.888 −0.01 0.744
Estimate 164 249 1% 0.769 1% 1% −0.1% 0.882 0.00 0.890 0.00 0.981
BMI Estimate 191 276 0% 1.000 0% 0% −0.1% 0.733 0.01 0.514 0.01 0.386

Impaired fasting glucose (≥6.1 mmol/L = 110 mg/dL)
DXA BIA InBody 70 343 −1% 0.901 −4% 3% 3.5% 0.009 −0.01 0.584 0.01 0.462
BMI 80 387 6% 0.394 3% 4% 3.2% 0.009 0.00 0.900 0.00 0.918
Estimate 80 387 3% 0.616 0% 3% 2.6% 0.023 0.02 0.438 0.01 0.796
BIA InBody BMI 70 343 7% 0.341 6% 1% −0.7% 0.609 0.02 0.648 −0.02 0.504
Estimate 70 343 2% 0.754 1% 1% −1.5% 0.205 0.04 0.253 −0.01 0.799
BMI Estimate 80 387 −3% 0.251 −3% -1% −0.6% 0.176 0.02 0.315 0.01 0.248

Metabolic syndrome (AHA/NHBLI)s
DXA BIA InBody 144 268 −4% 0.400 −6% 2% −0.7% 0.691 −0.03 0.120 0.01 0.625
BMI 165 301 4% 0.461 0% 4% 2.5% 0.257 −0.02 0.610 0.02 0.309
Estimate 165 301 3% 0.519 −1% 4% 1.7% 0.407 −0.02 0.466 0.02 0.329
BIA InBody BMI 144 268 3% 0.595 2% 1% 0.9% 0.662 0.01 0.697 0.01 0.429
Estimate 144 268 4% 0.480 2% 1% 0.8% 0.681 0.01 0.812 0.01 0.409
BMI Estimate 165 301 −1% 0.577 −1% 0% −0.7% 0.252 −0.01 0.622 0.00 0.958

aMethod of measurement, based on which participants are classified in categories of obesity.

bDifferent method of estimating obesity, the predictive power of which is compared to reference model/reference method.

cNumber of participants.

dNumber of participants that are positive with regard to respective outcome.

eNumber of participants that are negative with regard to respective outcome.

fPercentage improvement (+) or deterioration (−) in predictive power of new model compared to reference model. Categories of obesity/FM% as independent variable.

gNet reclassification of cases + net reclassification of non-cases. A positive number denotes increased predictive power for the new model.

hLikelihood of net reclassification index to be 0, that is, the new model showing no improvement/deterioration over reference model.

iNet reclassification of cases = percentage of cases reclassified by the new model into a higher risk category − percentage of cases reclassified by the new model into a lower risk category.

jNet reclassification of non-cases = percentage of non-cases reclassified by the new model into a lower risk category − percentage of non-cases reclassified by the new model into a higher risk category.

kIntegrated discrimination improvement (+) or deterioration (−) of new model compared to reference model. Categories of obesity/FM% as independent variable in an age-adjusted model.

lMean difference in predicted individual probabilities between cases and non-cases for two models. A positive number denotes increased predictive power for the new model.

mLikelihood of net reclassification index to be 0, that is, the new model showing no improvement/deterioration over reference model.

nMeasures of obesity (BMI/FM%) as continuous variable in a logistic regression model predicting respective outcomes.

oDifference in area under curve of receiver operating characteristic compared to reference method.

pProbability of 0-hypothesis (no difference).

qEstimation of FM% with bioimpedance device InBody (720) (Biospace, Korea).

rAnthropometry-based estimate; arithmetic mean of FM% estimations according to prediction methods Deurenberg et al. [12], Gallagher et al. [15], and Larsson et al. [14].

sDefinition of metabolic syndrome suggested by the common task force from the IDF and the American Heart Association/National Heart, Lung and Blood Institute (AHA/NHBLI) [17].