Table 2. Association of binary variables and pain score on univariate analysis.

Variable	Mean ± standard deviation score (95% CI)	P Value
Sex
Female	5.00 ± 2.91 (4.61–5.39)
Male	5.05 ± 2.98 (4.55–5.55)	0.86
Opioid-agent prescription
Yes	6.84 ± 2.94 (6.36–7.32)
No	4.48 ± 2.08 (4.13–4.83)	<0.001
Depression
Yes	6.19 ± 2.52 (5.67–6.71)
No	4.58 ± 2.94 (4.22–4.95)	<0.001
Post-traumatic Stress Disorder
Yes	6.14 ± 2.48 (3.85–8.44)
No	4.96 ± 2.93 (4.64–5.27)	0.29
Fibromyalgia
Yes	6.77 ± 2.07 (5.86–7.69)
No	4.86 ± 2.93 (4.54–5.18)	0.003
Illicit drug use
Yes	6.89 ± 2.58 (5.60–8.18)
No	4.88 ± 2.91 (4.55–5.20)	0.004
Antidepressant prescription
Yes	5.76 ± 2.77 (5.15–6.36)
No	4.73 ± 2.96 (4.37–5.09)	0.005
Gabapentinoid prescription
Yes	6.14 ± 2.53 (5.36–6.92)
No	4.82 ± 2.96 (4.48–5.15)	0.006
Alcohol use
Yes	4.53 ± 2.73 (4.10–4.96)
No	5.36 ± 3.04 (4.91–5.81)	0.009
Health insurance
Yes	4.90 ± 2.93 (4.57–5.22)
No	6.27 ± 2.66 (5.27–7.26)	0.01
Smoking
Yes	5.82 ± 2.39 (5.18–6.46)
No	4.85 ± 2.99 (4.50–5.19)	0.02
Previous knee injection
Yes	5.47 ± 2.94 (4.92–6.02)
No	4.75 ± 2.92 (4.37–5.13)	0.03
Surgery recommended by clinician
Yes	5.69 ± 2.94 (4.92–6.02)
No	4.87 ± 2.92 (4.53–5.20)	0.04

Abbreviation: CI, confidence interval.