CRP and rheumatoid arthritis: For subgroups of seropositive and seronegative patients based on age, sex, BMI, and RA therapy, the MBDA score was significantly associated with the DAS28-CRP (P < 0.05) in all but the 2 smallest subgroups of patients (seronegative men: n = 26; P = 0.84 and seronegative RA patients treated with anti-TNF medications: n = 28; P = 0.06).