Fig. 1

Comparison of LIs normalized by immunoassay cortisol and LC–MS/MS steroids in unilateral primary aldosteronism that was classified by LC–MS/MS results at A pre-ACTH and B post-ACTH stimulation AVS. All LC–MS/MS steroid-normalized LIs (except for that normalized by 18-oxocortisol) were higher than the immunoassay cortisol-normalized LIs (all P < 0.01). A pairwise within-patient comparison was performed using a Wilcoxon signed-rank test. The boxes represent the median, and the horizontal line marks the interquartile range. ACTH adrenocorticotropic hormone, IA immunoassay, LC–MS/MS liquid chromatography–tandem mass spectrometry, LI lateralization index, PA primary aldosteronism