Improvement in BMI z-score following adenotonsillectomy in adolescents aged 12–18 years: a retrospective cohort study

Table 4 BMI z-score changes up to 3 years following T&A based on BMI z-score category prior to surgery

BMI z-score Categories	Z-score BMI Before	Median Z score at 3 years	P-value
Normal	N = 127	N = 127	0.140
Mean	−0.1665	−0.11
Median	0.0500	0.14
Std. Deviation	0.83631	1.024
Percentiles
25	−0.7600	−0.6500
50	0.0500	0.1400
75	0.5100	0.6300
Overweight	N = 74	N = 74	0.798
Mean	1.5082	1.48
Median	1.5250	1.53
Std. Deviation	0.30918	0.504
Percentiles
25	1.5082	1.48
50	1.5250	1.53
75	0.30918	0.504
Obesity	N = 33	N = 33	0.064
Mean	2.2882	2.00
Median	2.2100	2.17
Std. Deviation	0.24558	0.730
Percentiles
25	2.1150	1.8650
50	2.2100	2.1700
75	2.4000	2.4250
Thinness	N = 6	N = 6	0.046
Mean	−2.4000	−0.59
Median	−2.3350	−0.64
Std. Deviation	.31875	1.707
Percentiles
25	−2.5950	−1.7000
50	−2.3350	−0.6350
75	−2.1775	0.7675
Severe thinness	N = 2	N = 2	0.180
Mean	−3.6900	−1.11
Median	−3.6900	−1.11
Std. Deviation	0.35355	1.273
Percentiles:
25	−3.9400	−2.0100
50	−3.6900	−1.1100
75

ISSN: 1471-2431