A prospective study was performed to continuously collect data from @ patients ( age range from @ to @ years , male versus female @/@ ) whose BMIs were less than @ kg/m <formula> ^ -LCB- @ -RCB- </formula> ( group A ) and @ patients ( age range from @ to @ years , male versus female @/@ ) whose BMIs were equal to or more than @ kg/m <formula> ^ -LCB- @ -RCB- </formula> ( group B ) .