Compared with the corresponding baseline values , there was no significant increase in the activity product for calcium oxalate when taking calcium with meal ( 0.54 + / - 0.25 vs. 0.57 + / - 0.22 , P = 0.54 ) , but it was increased significantly when calcium supplement was taken at bedtime ( 0.47 + / - 0.21 vs. 0.72 + / - 0.27 , P < 0.01 ) .
