TABLE 3. Average weight loss, reduction of BMI and percentage of loss of excess weight per time interval of postoperative vertical gastrectomy .

Time interval of postoperative	n	Average of weigh loss (kg) ±SD	Average of BMI reduction (kg/m²) ±SD	Excess weight loss % (EWL%)* ±SD	p
0 to 6 months	3	31.67±16.77	10.53±3.83	75.60±7.97	<0.01
7 to 12 months	25	38.36±8.94	13.73±2.8	80.82±20.43	<0.01
More than 12 months	19	45.83±12.12	16.32±3.99	93.13±27.42	<0.01
TOTAL	47	40.95±11.42	14.57±3.69	85.46±23.6

%EWL= BMI before - after BMI) * 100 / (BMI before - ideal BMI)