text: weighted analytic models for each type of healthcare 
  service. 
  
  Utilization of individual services 
  Opioids 
  Comorbidity index score (i.e. CCI), baseline pain and 
  change in pain were consistent predictors between the 
  models of opioid utilization. In these models, higher pain 
  (OR = 1.70–1.76, 
  (OR = 1.54–1.60, 
  p < 0.001) and increase in pain (OR = 1.70–1.71, p < 0.001) 
  were associated with higher odds of opioid utilization. 
  These models explained approximately 30% of the variation 
  in opioid use. 
  
  Any healthcare 
  for any healthcare 
  The final parsimonious models 
  utilization differed slightly between complete case and 
  weighted analyses (Table 6). Included in the models were 
  chronicity of symptoms, CCI, baseline pain, baseline dis- 
  ability, and change in pain from baseline to 4-week 
  follow-up. However, only baseline disability (OR = 1.48– 
  2.47, p < 0.05) and change in pain (OR = 1.28–1.45, 
  p < 0.05) were significant predictors in both models, with 
  greater baseline disability and worsening pain associated 
  with higher odds of any utilization. 
  
  p < 0.001),  CCI 
  
  Injection 
  A combination of race, chronicity and baseline disability 
  explained slightly more than 20% of the variance in 