. Author manuscript; available in PMC: 2011 Sep 27.

Published in final edited form as: Arch Phys Med Rehabil. 2009 Oct;90(10):1708–1715. doi: 10.1016/j.apmr.2009.04.020

Table 2.

Comparison of those with and without missing data.

Variable	Participants	Complete Data		Missing Data
		Complete Data		Missing Data		p -value of χ²

		N =1209	%	N=177	%
Number of Deaths		179	14.8	45	25.1	0.0003
Injury Classification
C1–C4, non-ambulatory		160	13.2	15	13.2	0.80
C5–C8, non-ambulatory		368	30.4	36	31.6	0.83
Non-cervical, non-ambulatory		423	35	41	36	0.63
Cervical, ambulatory		131	10.8	10	8.77	0.55
Non-cervical, ambulatory		127	10.5	12	10.5	0.12
Biographic
	White	917	75.8	79	69.3	0.02
	Men	906	74.9	76	66.7	0.04
Age at injury (Mean±SD)		31.34 ± 13.33		35.41 ± 17.76		0.0005^*
Years since injury (Mean±SD)		8.90 ± 6.96		8.54 ± 6.15		0.52^*

t-test comparing 2 means