injection utilization, however the only significant indi-
vidual predictor was baseline disability. In both models,
each 1-standard deviation increase in disability was
associated with approximately twice the odds of receiv-
ing injection (OR = 2.14, p < .01). The pseudo-R 2 value
for these models was lowest of all specific healthcare
Table 6 Parsimonious multivariate logistic regression model results for prediction of any care and individual service utilization ( n =
246) a
Dependent
variable
Independent variable Complete case Inverse probability of attrition weighted
B S.E. Sig. Odds ratio Pseudo R 2 B S.E. Sig. Odds ratio Pseudo R 2
Any care Chronicity 0.79 0.38 0.04 2.19 0.30 0.73 0.41 0.07 2.08 0.31
Baseline pain 0.37 0.12 0.002 1.45
CCI 0.21 0.12 0.07 1.23 0.31 0.14 0.03 1.36
Baseline disability 0.39 0.20 0.05 1.48 0.90 0.19 < 0.001 2.47
Change in pain 0.37 0.11 < 0.001 1.45 0.25 0.10 0.02 1.28
Opioids Surgery for condition 0.33 0.95 0.49 0.51 2.58 0.36
Chronicity 1.03 0.59 0.08 2.80
CCI 0.43 0.13 < 0.001 1.54 0.47 0.14 < 0.001 1.60
Baseline pain 0.53 0.13 < 0.001 1.70 0.57 0.15 < 0.001 1.76
Baseline 10-item OSPRO-YF 0.01 0.03 0.96 1.00
Change in pain 0.54 0.14 < 0.001 1.71 0.53 0.15 < 0.001 1.70
Additional OSPRO-YF 7-items (baseline) −0.09 0.05 0.08 0.92 −0.01 0.05 0.07 0.91
Injection Race (non-white) b −1.79 1.05 0.09 0.17 0.22 −2.15 1.19 0.07 0.12 0.24
Chronicity 1.27 0.65 0.05 3.57 1.31 0.73 0.07 3.71
Baseline disability 0.76 0.20 < 0.01 2.14 0.76 0.21 < 0.01 2.14
Surgery CCI 0.30 0.15 0.10 0.15 1.16 0.34
Baseline disability 1.14 0.28 < 0.001 3.13 1.18 0.31 < 0.001 3.25
Change in 10-item OSPRO-YF score 0.12 0.05 0.03 1.12 0.13 0.06 0.02 1.14
Change in disability 1.11 0.42 0.01 3.04 1.12 0.44 0.01 3.05
Diagnostic tests
or imaging
Chronicity 0.60 0.43 0.16 1.82 0.29 0.33
CCI 0.30 0.12 0.02 1.35 0.37 0.13 < 0.001 1.45
Baseline disability 0.81 0.18 < 0.001 2.25 0.98 0.19 < 0.001 2.66
Change in pain 0.34 0.11 < 0.001 1.41 0.37 0.11 < 0.001 1.45
Emergency
room
Age −0.09 0.03 < 0.001 0.91 0.48 −0.06 0.03 0.03 0.94 0.50
Anatomical location (neck) c 0.54 0.97 0.58 1.71 −0.37 0.92 0.69 0.69
Anatomical location (low back) c 0.72 0.95 0.45 2.05 −0.04 0.89 0.97 0.96
Anatomical location (shoulder) c −2.86 1.49 0.06 0.06 −3.52 1.53 0.02 0.03
Insurance (public) d 1.89 1.06 0.08 6.65 1.81 1.11 0.10 6.11
Insurance (other) d 2.20 0.88 0.01 8.99 2.58 0.86 < 0.001 13.15
Chronicity 1.76 1.26 0.16 5.81
Surgery for condition 1.69 0.94 0.07 5.43 1.77 0.93 0.06 5.86
Baseline disability 1.59 0.47 < 0.001 4.88 1.20 0.34 < 0.001 3.33
Additional OSPRO-YF 7-items (baseline) −0.20 0.09 0.03 0.82
Change in 10-item OSPRO-YF score 0.14 0.07 0.05 1.15
Change in pain 0.57 0.22 0.01 1.77 0.46 0.21 0.03 1.59
CCI Charlson comorbidity index, OSPRO-YF Pain-related psychological distress screening tool
a Health care utilization (dependent) variables refer to utilization during the follow-up period, whereas independent variables refer to measurements taken before
the follow-up period
b Reference value is White
c Reference value is knee
d Reference value is private insurance
Lentz et al. BMC Health Services Research  (2018) 18:648 Page 9 of 14