Results
Approximately one in 333 (0.3%) patients hospitalized for an isolated fracture and one in 47 (2.1%) patients with musculoskeletal infection left against medical advice. Patient characteristics associated with self-discharge included age < 75 years (trauma: odds ratio [OR] 2.7, 95% confidence interval [CI] 2.5–2.8, p < 0.001; infection: OR 3.9, 95% CI 3.8–4.1, p < 0.001), male sex (trauma: OR 1.7, 95% CI 1.7–1.8, p < 0.001; infection: OR 1.4, 95% CI 1.3–1.4, p < 0.001), black race/ethnicity (trauma: OR 1.5, 95% CI 1.4–1.6, p < 0.001; infection: OR 1.1, 95% CI 1.1–1.1, p < 0.001), low household income (trauma: OR 1.5, 95% CI 1.4–1.5, p < 0.001; infection: OR 1.4, 95% CI 1.4–1.4, p < 0.001), nonprivate insurance (Medicare [trauma: OR 1.7, 95% CI 1.6–1.8, p < 0.001; infection: OR 2.5, 95% CI 2.4–2.5, p < 0.001] and Medicaid [trauma: OR 2.6, 95% CI 2.5–2.7, p < 0.001; infection: OR 3.2, 95% CI 3.2–3.3, p < 0.001]), and no insurance coverage (trauma: OR 3.0, 95% CI 2.9–3.1, p < 0.001; infection: OR 3.5, 95% CI 3.4–3.5, p < 0.001), less medical comorbidity (trauma: OR 0.94 per one-unit increase in the number of comorbidities, 95% CI 0.93–0.95, p < 0.001; infection: OR 0.88, 95% CI 0.87–0.88, p < 0.001), alcohol (trauma: OR, 2.3, 95% 2.2–2.4, p < 0.001; infection: OR 1.5, 95% CI 1.5–1.5, p < 0.001), opioid (trauma: OR 2.9, 95% CI 2.7–3.1, p < 0.001; infection: OR 4.4, 95% CI 4.3–4.4, p < 0.001) and nonopioid drug abuse (trauma: OR, 2.0, 95% CI 1.9–2.1, p < 0.001; infection: OR 2.8, 95% CI 2.8–2.9, p < 0.001), psychosis (trauma: OR 1.3, 95%CI 1.2–1.3, p < 0.001; infection: OR 1.3, 95% CI 1.3, 1.4, p < 0.001), and AIDS/HIV infection (trauma: OR 1.5, 95% CI 1.2–1.8, p < 0.001; infection: OR 1.3, 95% CI 1.3–1.4, p < 0.001). Patients with upper extremity fractures (OR 1.9, 95% CI 1.8–1.9, p < 0.001) or fractures of the neck and trunk (OR 2.1, 95% CI 2.0–2.2, p < 0.001) were more likely to leave against medical advice than patients with lower extremity fractures. Among infection hospitalizations, patients with cellulitis had the highest odds of self-discharge compared with carbuncle/furuncle (OR 1.3, 95% CI 1.2–1.5, p < 0.001). Self-discharges were more likely to occur at hospitals of larger size (trauma: OR 1.2, 95% CI 1.1–1.2, p < 0.001; infection: nonsignificant), located in urban settings (trauma: OR 1.3, 95% CI 1.2–1.4, p < 0.001; infection: OR 1.6, 95% CI 1.5–1.6, p < 0.001), and in the Northeast (trauma: OR 1.7, 95% CI 1.6–1.8, p < 0.001; infection: OR 1.6, 95% CI 1.6–1.6, p < 0.001) than at small, rural hospitals in the South.