↵^a All data are presented as number (%), unless stated otherwise. Missing values ranged from 0% to 12%.

^b Hazardous drinking was measured with the Alcohol Use Disorders Identification Test (AUDIT-C) (range=0–12); ≥3 in women and ≥4 in men is considered risk of hazardous drinking.^31,32

^c Measured with a numeric rating scale as an average of the previous week (range=0–10); 0 indicates “no pain,” 10 indicates “worst pain imaginable.”

^d Measured with the 36-Item Short-Form Health Survey (range=0–100); higher score indicates higher quality of life.^25–27

^e Measured with the Center for Epidemiologic Studies Depression Scale (CES-D) (range=0–60); higher score indicates more prone to depression.²⁸

^f Measured with the Pain Catastrophizing Scale (range=0–52); higher score indicates more risk for catastrophizing.²⁹

^g Measured with the Back Beliefs Questionnaire (range=9–49); higher score indicates more positive thoughts of recovery.³⁰

^h Oral or inhalation corticosteroid use for >90 days.

ⁱ Measured with heel bone densitometry.

^j Measured with the Roland-Morris Disability Questionnaire (range=0–24); 0 indicates no disability.²⁴ A cutoff value of 17 was used to indicate severe disability.