Table 2.

Multivariate Model Predicting Clinically Significant Weight Gain (7%) at One Year from Baseline Variables Associated Bivariately with Weight Gain

Baseline Predictor	Adjusted OR^	95% CI	P-value
Age, yr (ref = 35 – 44)			0.14
≤ 24	1.12	0.60 – 2.08
25 – 34	1.41	0.91 – 2.19
45 – 54	0.96	0.61 – 1.51
≥ 55	0.59	0.29 – 1.21
Gender (ref=male)			< 0.001
Female	2.17	1.54 – 3.07
Fast pace (ref=strongly disagree /disagree)			0.40
Agree	1.20	0.75 – 1.92
Strongly agree	1.43	0.89 – 2.30
Return to paid work by baseline interview (ref=Yes, same job)			0.30
Yes, light duty or different job	1.00	0.62 – 1.60
No	1.35	0.87 – 2.10
Pain interference with daily activities, past week (0=no interference, ref=0-3)39			0.58
4 – 5	0.92	0.55 – 1.53
6 – 7	1.29	0.75 – 2.21
8 – 10	0.93	0.53 – 1.64
Current health aside from injury (ref=excellent)			0.14
Very good	1.12	0.67 – 1.85
Good	1.45	0.87 – 2.40
Fair/poor	1.86	1.00 – 3.45
Specialty, first provider seen for injury ◇ (ref=primary care)			0.15
Occupational medicine	1.85	0.97 – 3.53
Chiropractor	1.43	0.94 – 2.18
Other	1.08	0.70 – 1.67
Catastrophizing ‡‡ (ref=0-1)			0.38
Low (>1 – <2)	1.29	0.76 – 2.21
Moderate (2 – <3)	0.92	0.56 – 1.51
High (3 – 4)	1.29	0.76 – 2.22
Recovery expectations32 (0-10 scale, ref=10, 10 = extremely certain will be working in 6 month)			0.08
High (7 – 9)	1.45	0.92 – 2.28
Low (0 – 6)	1.53	1.00 – 2.33
SF-36 v2 Mental Health (ref=>50)39			0.86
41 – 50	0.89	0.56 – 1.42
≤ 40	0.99	0.62 – 1.57

^{^}Adjusted for all other variables in the multivariate model.

Each baseline variable included in this table was associated significantly (P < 0.10) in bivariate analyses with clinically significant weight gain by one year of initial occupational back injury.

Age was included as an adjusting variable.

Missing, “don't know,” and refusal responses for each variable were combined into one response for each variable (results not shown)

Ref indicates reference group.