Adjusted changes of IBS-SSS for baseline covariates showed statistically significant reduction of IBS-SSS in LFD group compared to ND ( IBS-SSS score 75 ; 95 % CI : 24-126 , P < 0.01 ) , but not in LGG compared to ND ( IBS-SSS score 32 ; 95 % CI : 18-80 , P = 0.20 ) .