. Author manuscript; available in PMC: 2018 Jul 1.

Published in final edited form as: J Pediatr Gastroenterol Nutr. 2017 Jul;65(1):40–46. doi: 10.1097/MPG.0000000000001557

Table 3.

Principal component analysis (PCA) and partial least squares (PLS) regression models for environmental enteric dysfunction (EED) score development

Biomarker¹	PCA Component Loadings										PLS Component Loadings

	Model 1		Model 2²			Model 3					Model 1	Model 2	Model 3²

	Comp. 1	Comp. 2	Comp. 1	Comp. 2	Comp. 3	Comp. 1	Comp. 2	Comp. 3	Comp. 4	Comp. 5	Comp. 1	Comp. 1	Comp. 1
MPO	0.58	0.10	0.36	−0.42	0.10	0.08	0.36	−0.34	0.26	0.22	0.71	0.54	0.48
AAT	0.68	0.12	0.29	−0.60	−0.12	0.06	0.32	−0.47	0.34	0.21	0.62	0.46	0.45
NEO	−0.28	0.40	0.10	0.46	−0.05	0.08	0.05	0.35	−0.34	0.19	0.32	0.26	0.25
GLP-2	−0.24	−0.57	−0.13	0.20	0.73	−0.09	−0.08	0.46	0.51	0.01	0.01	−0.01	0.05
EndoCAb IgG	−0.23	0.70	−0.01	0.30	−0.65	0.12	−0.17	0.04	−0.30	0.72	−0.10	−0.07	−0.08
CRP			0.63	0.21	0.02	0.38	0.45	0.09	−0.16	−0.01		0.48	0.41
AGP			0.60	0.29	0.13	0.43	0.40	0.23	−0.11	−0.06		0.43	0.38
EndoCAb IgM						0.22	−0.43	−0.36	−0.07	−0.06			−0.27
EndoCAb IgA						0.27	−0.28	0.04	0.27	0.49			0.08
Total IgG						0.22	−0.08	0.27	0.48	−0.02			0.07
Total IgM						0.49	−0.29	−0.22	−0.07	−0.29			−0.08
Total IgA						0.47	−0.12	0.11	0.09	−0.15			0.30

% of X variance³	27.82	21.46	24.67	19.07	15.18	16.69	14.41	10.99	9.85	9.08	23.77	22.08	12.88
% of Y variance⁴	2.26		3.42			4.99					5.21	5.44	8.64

Biomarkers were log-transformed and outliers removed prior to analysis. Gray shaded boxes indicated biomarkers not included in the model presented in that column.

PCA Model 2 is the source of the PCA scores used in subsequent analyses: component 1 is the systemic inflammation (SI) score, component 2 is the gut inflammation (GI) score and component 3 is the gut permeability (GP) score. PLS model 3 is the source of the PLS score used subsequently.

Percent of total variance in independent variables (biomarkers) explained by each factor.

⁴

Percent of variance in L:M explained by each score model (generated by PLS command; for PCA, based on R² from regression of log-transformed L:M on PCA components).

Abbreviations: AAT, α-1 antitrypsin; AGP, α-1 acid glycoprotein; Comp, component; CRP, C-reactive protein; EED, environmental enteric dysfunction; EndoCAb, endotoxin core antibody; GLP-2, glucagon-like peptide-2; IgA, immunoglobulin A; IgG, immunoglobulin G; IgM, immunoglobulin M; L:M, lactulose:mannitol ratio; MPO, myeloperoxidase; NEO, neopterin; PCA, principal component analysis; PLS, partial least squares.