Figure 1
Inclusion and exclusion criteria. Initially, 8 797 787 patients with LBP were identified. Patients with an insufficient clean period (LBP within the last 1 year), patients with a diagnosis of LBP that was not in the first position of their diagnosis and LBP in only inpatient settings were excluded, reducing the number of patients to 4 263 713. Patients were excluded if they were not continuously enrolled in their insurance for 24 months before and after the initial LBP visit and if they were aged <18 years, reducing the number of patients to 422 871. Patients with exclusionary conditions, LBP that was not limited to the low back, patients with back procedures in the 12 months prior to the index LBP visit and patients with any opioid use in the 12 months before the index visit were excluded, leaving 216 504 patients in our sample.