Multivariate analyses of haemoglobin changes (in g/dL) according to different definitions of iron status profile, stratified by mGFR classes.

Abbreviations: BIC Bayesian Information Criterion; AIC, Akaike information Criterion. TSAT, transferrin saturation; TIBC, transferrin iron-binding capacity; ID, iron deficiency; Ref, reference class.1See BOX 1 for definitions of iron indexes.2BIC and AIC were given for the multivariate model taking into account the interaction term between mGFR and iron tests. Best values for BIC and AIC are underlined.3Regression coefficients for the different iron indexes in the linear regression models of Hb levels, stratified by mGFR classes. Models are adjusted for age, gender, ethnicity, smoking, diabetic nephropathy, renin angiotensin system inhibitors and oral iron use, C-reactive protein, serum folic acid, serum albumin, and centre.