Figure 2: The scatter plots display the strongest correlation between the GLCM texture features and the activity of scintigraphy, with linear regression fit (solid lines) and 95% confidence intervals (gray bands). Spearman's rho was calculated to test the association. For all parotid glands (n = 22), the CON shows significantly moderate negative correlation to the MAR, and the HOM shows significantly high positive correlation to EF. For the subgroup of parotid glands with the semiquantitative OMERACT US score of one (n = 10), the CON tended to be negatively associated with MAR, whereas the HOM still yielded significantly high positive correlation to EF. For the subgroup of parotid glands with the semiquantitative OMERACT US score of two (n = 9), the CON yielded significantly high negative correlation to the MAR, while the HOM tended to be positively associated with EF. These findings suggest that GLCM CON and HOM were better markers for discriminating the activity of scintigraphy compared with the semiquantitative scoring system (*P < 0.05; **P < 0.01). GLCM: Gray-level co-occurrence matrix, CON: Contrast, MAR: Maximum accumulation ratio, HOM: Homogeneity, EF: Excretion fraction, OMERACT: Outcome measures in rheumatoid arthritis clinical trials, US: Ultrasound