Towards objective measurements of habitual dietary intake patterns: comparing NMR metabolomics and food frequency questionnaire data in a population-based cohort

Table 3 OPLS model statistics from analyses of data from 1,895 participants in the Västerbotten Intervention Programme

Model	Nr of Lv¹	n	R2X[cum]²	R2Y[cum]³	Q2[cum]⁴	CV-ANOVA⁵ (p-value)	ROC AUC⁶	Permutation test (Q2)⁷	Classification (Q1/Q4)
PCA-X	7	1,895	0.408		0.318
OPLS Back-ground data⁸	4 + 1 + 0	1,895	0.279	0.204	0.163	< 0.00001
OPLS rMDS⁹	1 + 1 + 0	1,895	0.160	0.0794	-0.0372	< 0.0000001
OPLS-DA rMDS Q1 vs. Q4	1 + 1 + 0	1002	0.184	0.122	0.0472	< 0.0000001	0.71/0.71	0.0663¹⁴	50%/78%
OPLS HDS¹⁰	1 + 0 + 0	1,895	0.148	0.0194	0.00924	0.00015
OPLS PDI¹¹	1 + 0 + 0	1,895	0.184	0.0608	0.021	< 0.0000001
OPLS-DA PDI Q1 vs. Q4	1 + 0 + 0	913	0.0450	0.0664	0.00473	1	0.65/0.65	-0.0340¹⁴	42%/75%
OPLS hPDI¹²	1 + 0 + 0	1,895	0.100	0.0206	-0.000529	0.116
OPLS uPDI¹³	1 + 1 + 0	1,895	0.199	0.0776	0.0388	< 0.0000001
OPLS-DA uPDI Q1 vs. Q4	1 + 1 + 0	993	0.186	0.144	0.0589	< 0.0000001	0.72/0.72	-0.0742¹⁴	59%/70%
OPLS men time period 1 clusters	1 + 0 + 0	799	0.120	0.0381	-0.000576	1
OPLS women time period 1 clusters	0 + 0 + 0	668

1 Latent Variables; 2 Cumulative fraction of the sum of squares of X explained by the selected latent variables; 3 Cumulative fraction of the sum of squares of Y explained by the selected latent variables; 4 Cumulative fraction of the sum of squares predicted by the selected latent variables, estimated by cross-validation; 5 Analysis Of Variance testing of Cross-Validated predictive results; 6 Receiver Operating Area under the curve; 7 the intercept between real and random models, degree of overfit. 8 y-values included BMI, age, time, sex, education, 9 y-value included MDS, 10 y-value included HDS, 11 y-value included PDI, 12 y-value included hPDI, 13 y-value included uPDI, 14 High quality permutation test
Abbreviations: PCA, principal component analysis; OPLS, orthogonal projections to latent structures; OPLS-DA, orthogonal projections to latent structures discriminant analyses; BMI, body mass index; DII, Diet Inflammatory Index; rMDS, relative Mediterranean Diet Score; HDS, Healthy Diet Score; Q, first quartile; Q4, fourth quartile; PDI, plant based diet index; hPDI, healthful plant based diet index; uPDI, unhealthful plant based diet index

ISSN: 1475-2891