Table 2. Correlation by Operative State.

Associations between ODI and NDI among PROMIS physical function scores, pain interference scores, and pain behavior scores were quantified using Pearson’s correlation coefficient for all visits and are shown for between pre-operative and post-operative visits as well. All Correlations were found to be significant with p-values below 0.05. The number of observations at each time-point is given in in parenthesis (N). This analysis shows that both PROMIS physical function and pain interference are strongly correlated with the ODI and NDI post operatively, while Pre-operative correlations are more moderate. Pain behavior assessments are also more moderately correlated with both ODI and NDI.

	ODI			NDI
	All data	pre-op	post-op	All data	pre-op	post-op
Physical Function	0.8264(246)	0.7604(178)	0.8468(68)	0.8482(72)	0.8334(52)	0.8710(20)
Pain interference	0.7422(170)	0.6133(118)	0.8907(52)	0.7213(52)	0.6544(38)	0.8875(14)
Pain Behavior	0.7601(75)	0.7226(59)	0.8273(16)	0.5846(20)	0.7367(14)