Methodologic considerations in the design and analysis of nested case-control studies: association between cytokines and postoperative delirium

Table 5 Association between Match Factors and interleukin-6 (IL-6) from Controls

	PREOP (%)	PACU (%)	POD2 (%)
Combined Match Factor R-squared	22.3	18.5	21.8
Individual Match Factor
Partial R-squared
Age at Surgery	3.69	7.63	0.27
Baseline GCP	4.12	1.17	1.34
Gender	8.62	8.38	7.65
Surgery Type	0.37	0.37	1.96
Vascular Comorbidity	1.00	0.28	8.76
APOE	4.45	0.62	1.84

R-squared estimated from the general linear model where IL-6 was the dependent variable, and the six match factors were the independent variables. None of the variables were statistically significant in the linear models except Gender in the PREOP period
GCP general cognitive performance, APOE apolipoprotein E

ISSN: 1471-2288