Table 1. Stratified IPTW-Adjusted Treatment Estimates for the Primary Outcome of 1-Year Success Rate of Nonoperative Management of Appendicitis.

Factors	No. of patients with medical record review	Success rate of nonoperative management at 1 y, No. (%) [95% CI]	P valuea
Patient age, y
≤10	93	59 (63.8) [52.7-73.5]	.47
>10	277	189 (68.1) [62.0-73.7]
Annual household income, $
<50 000	109	72 (65.9) [55.7-74.9]	.70
≥50 000	217	148 (68.3) [61.3-74.5]
Transfer status
Not transferred	211	144 (68.3) [61.3-74.6]	.60
Transferred	159	104 (65.6) [57.1-73.1]
Sexb
Male	229	155 (67.8) [60.9-74.0]	.72
Female	141	93 (65.9) [57.3-73.6]
Race and ethnicityb,c
Non-Hispanic White	199	140 (70.4) [63.2-76.8]	.14
Other race/ethnicity	171	107 (62.7) [54.6-70.1]
Insurance statusb
Private insurance	251	176 (70.0) [63.6-75.7]	.20
Medicaid	109	68 (62.5) [52.2-71.7]
Primary caregiver educationb
Some college or less	149	105 (70.2) [61.8-77.5]	.42
At least college degree	190	125 (65.8) [58.3-72.6]
Primary language spoken at homeb
English	284	191 (67.1) [61.0-72.6]	.82
Other	69	47 (68.6) [56.1-78.9]

^aMain effects for 1-year success rate of nonoperative management were tested through inverse probability of treatment weight (IPTW) logistic regression models. In all models, inference relied on robust sandwich-type standard errors to account for the estimated IPTWs.

^bFactor was added to the analysis post hoc.

^cRace and ethnicity were assessed because of evidence from the available literature suggesting an association with outcomes in pediatric patients treated for appendicitis. Related data were reported by caregivers using surveys with predefined categories listed in the table. Other includes Black, Hispanic, Asian, American Indian, Alaska Native, and biracial patients. For patients managed nonoperatively, this included 23 non-Hispanic Black patients, 37 Hispanic patients, 106 patients who reported another race or ethnicity, and 5 patients who did not report race or ethnicity.