The Danish Chiropractic Low Back Pain Cohort (ChiCo) is a longitudinal observational cohort consisting of adults seeking care for LBP at 10 chiropractic clinics from the Central Denmark Region . Only medium or large size clinics were invited to ensure adequate recruitment of study participants within a reasonable timeframe. The thresholds for poor mental and physical health and ability to do everyday activities were set at the poorest quartile in the dataset. For pain medication, we reported odds ratios with 95% confidence intervals and p-values from a logistic regression model fitted with GEE. All these analyses were performed adjusting for age, BMI, sex, smoking status, employment status, cohabitation, education, pain duration, and presence of other musculoskeletal pain.