Individual predictors of healthcare utilization
Parsimonious model results were used to identify signifi-
cant individual predictors of health care utilization. Results
of the parsimonious models are listed in Table 6 and sum-
marized below. Variance explained (pseudo-R 2) values re-
ported in the summaries below are specific to performance
of individual parsimonious models, and are different than
pseudo-R2 values of the full multivariate models listed in
Table5. Comparison of adjusted odds ratios (OR) and 95%
confidence interval (CI) were used to determine the relative
strength of each predictor in the parsimonious models.
Odds ratios are reported from the parsimonious models as
these are intuitive, clinically interpretable predictive indices.
Summary findings for all utilization outcomes are presented
in Table 7. In summarizing results, we focus on predictors
that were identified consiste ntly across complete case and
Table 2 Baseline health-related information for the full cohort, and for those with complete and incomplete follow-up
Variable Label Full cohort at baseline
(n = 440)
Completed follow-up
(n = 246)
Did not complete follow-up
(n = 194)
p-value a
Health-related information
Anatomical region Neck 98 (22.3%) 48 (19.5%) 50 (25.8%) 0.27
Low Back 118 (26.8%) 66 (26.8%) 52 (26.8%)
Shoulder 107 (24.3%) 59 (24.0%) 48 (24.7%)
Knee 117 (26.6%) 73 (29.7%) 44 (22.7%)
Symptom onset Gradual 239 (54.3%) 146 (59.3%) 93 (47.9%) 0.03
Sudden 138 (31.4%) 65 (26.4%) 73 (37.6%)
Traumatic 63 (14.3%) 35 (14.2%) 28 (14.4%)
Duration of symptoms urgery
for condition
Mean ± SD 398.58 ± 1715.80 379.79 ± 1999.77 423.01 ± 1259.33 0.80
Median (min, max) 90 (0 – 29565) 90 (1 – 29565) 90 (0 – 10000)
Yes 83 (18.9%) 44 (17.9%) 39 (20.1%) 0.56
No 357 (81.1%) 202 (82.1%) 155 (79.9%)
Work-related injury (32 missing) Yes 63 (14.3%) 30 (12.2%) 33 (17.0%) 0.36
No 345 (78.4%) 198 (80.5%) 147 (75.8%)
Chronicity Acute 101 (23.0%) 65 (26.4%) 36 (18.6%) 0.05
Chronic 324 (73.6%) 173 (70.3%) 151 (77.8%)
Pain Intensity Mean ± SD 4.22 ± 1.98 3.94 ± 1.72 4.58 ± 2.21 0.01
Median (min, max) 4 (0 – 9.67) 4 (0 – 8) 4.5 (0 – 9.7)
Disability Mean ± SD 0 ± 1.0 −0.06 ± .97 0.08 ± 1.03 0.16
Median (min, max) −0.16 ( −2.41– 3.14) −0.23 ( −2.21– 2.94) −0.01 ( −2.41– 3.14)
CCI Mean ± SD 0.66 ± 1.47 0.68 ± 1.62 0.63 ± 1.25 0.76
Median (min, max) 0 (0 – 13) 0 (0 – 13) 0 (0 – 8)
CCI Charlson comorbidity index
a Group comparisons with independent samples t-tests for continuous variables and chi-square tests for categorical variables
Table 3 Baseline OSPRO questionnaire scores for the full cohort and for those with complete and incomplete follow-up
Variable Label Full Cohort at baseline
(n = 440)
Completed follow-up
(n = 246)
Did not complete follow-up
(n = 194)
p-value a
OSPRO-ROS 10-item Mean ± SD 2.68 ± 2.38 2.52 ± 2.24 2.89 ± 2.55 0.11
Median (min, max) 2 (0 – 10) 2 (0 – 10) 2.5 (0 – 10)
OSPRO-ROS + 13 items Mean ± SD 1.25 ± 1.80 1.14 ± 1.52 1.38 ± 2.09 0.17
Median (min, max) 1 (0 – 12) 1 (0 – 7) 1 (0 – 12)
OSPRO-YF 10-item Mean ± SD 17.43 ± 6.69 16.87 ± 6.46 18.15 ± 6.91 0.04
Median (min, max) 17 (4 – 47) 16 (4 – 40) 17 (4 – 47)
OSPRO-YF + 7 items Mean ± SD 14.92 ± 5.51 14.41 ± 4.93 15.57 ± 6.12 0.03
Median (min, max) 15 (3 – 34) 14 (3 – 28) 16 (3 – 34)
CCI Charlson comorbidity index, OSPRO-ROS Review of systems screening tool, OSPRO-YF Pain-related psychological distress screening tool
a Independent samples t-tests to assess group differences between those who did and did not complete follow-up
Lentz et al. BMC Health Services Research  (2018) 18:648 Page 7 of 14