Table 5. Days to last follow-up by surgical center.

Center	n	Average	SD	Max	Min	P value†
1	169	305	225	1,151	9	0.15
2	45	729	504	2,292	29	<0.01
3	126	261	215	1,120	27	<0.01
4	105	327	216	14	840	0.65
Total/average	445	341	293	2,292	9	1.00

^†, P value for each center in comparison to average for all centers.