Fig. 1From: The association between blood manganese and liver stiffness in participants with chronic obstructive pulmonary disease: a cross-sectional study from NHANES 2017–2018Subgroup analysis of the association between blood manganese and liver stiffness. '/' represented restricted sample size. All the covariates in Table 1 were adjusted. *In the subgroup analysis stratified by each covariate, the model is not adjusted for the stratification variable itself. BMI body mass index (kg/m2)Back to article page