Analysis of covariance models were used to compute within-group and between-group change in average symptom scores including treatment arm and geographic region as factors and baseline values as a covariate. Results: Of the 1,992 patients (994 LIN, 998 PBO) included in this study, similar demographic and baseline characteristics were identified between groups (Table 1). Baseline demographics, characteristics, and disease severity Placebo N = 1998 Linaclotide 145 μg N = 994 Total N = 1992 Patient Demographics Age, mean (SD) 46.7 (14.2) 47.5 (13.5) 47.1 (13.9) Female, n (%) 853 (85.5) 838 (84.3) 1691 (84.9) Race, n (%)  White 724 (72.5) 723 (72.7) 1447 (72.6)  Black or African American 237 (23.7) 235 (23.6) 472 (23.7)  Asian 24 (2.4) 20 (2) 44 (2.2)  American Indian or Alaska Native 1 (0.1) 5 (0.5) 6 (0.3)  Native Hawaiian or Other Pacific Islander 1 (0.1) 0 1 (0.1)  Multiple 3 (0.3) 4 (0.4) 7 (0.4)  Other 8 (0.8) 7 (0.7) 15 (0.8)  Hispanic or Latino, n (%) 237 (23.7) 236 (23.7) 473 (23.7) Baseline Characteristics Weight, kg, mean (SD) 78.46 (19.0) 78.11 (18.1) 78.28 (18.6) BMI, kg/m2, mean (SD) 28.74 (6.4) 28.64 (6.1) 28.69 (6.2) Disease Severity at Baseline Abdominal pain score, mean (SD) 2.51 (1.0) 2.48 (1.0) 2.50 (1.0) Abdominal discomfort score, mean (SD) 2.86 (1.0) 2.79 (1.0) 2.82 (1.0) Bloating score, mean (SD) 3.08 (0.9) 3.05 (0.9) 3.07 (0.9) SD, standard deviation.