Fig. 1
A schematic summary of the study design. (1) The top part represents the workflow of constructing IDSCN. First, a reference structural covariance network was constructed across all controls, where the edges represented partial Pearson correlations between the GMV for each pair of regions (PCCn) with age, gender, education, and ICV as covariates. Then, the added MCI k and all controls formed a new group to construct a perturbed network (PCCn+1). Finally, the IDSCN of MCI k was the Z-score of the difference between the perturbed network and the reference network. (2) The middle part represents the clustering analysis of MCI patients using K-means. (3) The bottom part represents statistical analysis, including comparisons of characteristics between subtypes and analysis of covariance edges. Abbreviations: CN = cognitively normal; GMV = gray matter volume; ICV = intracranial volume; IDSCN = individual differential structural covariance network; MCI = mild cognitive impairment; PCC = partial Pearson correlation