Table 3.

Univariate Effects of Sample Processing on RNA Quality Outcome

Name	≤4.5 RIN		≥6.5 RIN		Odds Ratio	95% CI	p-value

	n	%	n	%

Region of Pancreas Sampled^A							<0.01
Head	23	34%	45	66%	-	-	-
Body	14	82%	3	18%	0.11	(0.02–0.38)	<0.01
Tail	35	71%	14	29%	0.20	(0.09–0.45)	<0.01

Sample Type^B
Vials	43	44%	55	56%	-	-	-
Blocks	32	71%	13	29%	0.32	(0.15–0.67)	<0.01

Staff Performing RNA Extraction							0.53
#1	50	49%	51	51%	-	-	-
#2	23	59%	16	41%	0.68	(0.32–1.43)	0.32
#3	2	67%	1	33%	0.49	(0.02–5.27)	0.57

Sample Collection Procedures^C
Original Protocol	63	71%	26	29%	-	-	-
New Protocol	12	22%	42	78%	8.48	(3.96–19.30)	<0.01

Excluded 3 cases where region sampled was unknown

Vials contain minced tissue preserved in RNAlater; Blocks are composed of fresh frozen tissue embedded in OCT media. Vials and blocks represent total pancreatic RNA extracts. Laser capture islet-RNA was not included here.

Major difference is that, initially, after cleaning the pancreas, vials were routinely prepared following tissue block preservation but occasionally performed simultaneously, i.e. original protocol. Later, beginning with nPOD caseID 6170, vials were prepared first, before tissue block preservation, i.e. new protocol.