Table 3.
Predictors of Observation Stays That Exceed Forty-Eight or Seventy-Two Hours Estimated Using Hierarchal Linear Models
| Long OS Stay Defined as | >48 hours | >72 hours | ||||
|---|---|---|---|---|---|---|
| OR | CI Low | CI High | OR | CI Low | CI High | |
| Patient characteristics | ||||||
| Age (continuous) | 1.01 | 1.01 | 1.01 | 1.01 | 1.01 | 1.02 |
| Female (male reference) | 1.13 | 1.11 | 1.15 | 1.12 | 1.07 | 1.16 |
| Payer (Medicare reference) | ||||||
| Medicaid | 1.13 | 1.09 | 1.18 | 1.14 | 1.06 | 1.23 |
| Private | 0.61 | 0.60 | 0.63 | 0.60 | 0.57 | 0.64 |
| Uninsured | 1.18 | 1.13 | 1.23 | 1.31 | 1.21 | 1.42 |
| Other | 0.68 | 0.64 | 0.73 | 0.72 | 0.63 | 0.81 |
| Disposition (relative to Home/Home Health) | ||||||
| Discharged to skilled nursing facility | 2.71 | 2.57 | 2.85 | 3.54 | 3.28 | 3.83 |
| Left against medical advice | 0.57 | 0.49 | 0.67 | 0.56 | 0.41 | 0.77 |
| Died | 1.42 | 1.08 | 1.86 | 1.48 | 0.95 | 2.29 |
| All other | 1.54 | 1.47 | 1.61 | 1.97 | 1.83 | 2.12 |
| ZIP income quartile (relative to highest income) | ||||||
| 1st quartile (<$37,000/year) | 1.16 | 1.11 | 1.22 | 1.18 | 1.09 | 1.28 |
| 2nd quartile ($37,000 to <$46,000) | 1.09 | 1.05 | 1.14 | 1.07 | 0.99 | 1.15 |
| 3rd quartile ($46,000 to <$62,000) | 1.05 | 1.01 | 1.09 | 1.05 | 0.98 | 1.13 |
| CCS 102 Nonspecific chest pain | 0.57 | 0.56 | 0.59 | 0.51 | 0.48 | 0.54 |
| CCS 101 Coronary atherosclerosis | 0.81 | 0.77 | 0.85 | 0.69 | 0.63 | 0.77 |
| CCS 55 Fluid and electrolyte disorders | 1.19 | 1.12 | 1.26 | 1.12 | 1.01 | 1.24 |
| CCS 245 Syncope | 0.85 | 0.80 | 0.90 | 0.75 | 0.67 | 0.83 |
| CCS 251 Abdominal pain | 1.40 | 1.32 | 1.48 | 1.52 | 1.37 | 1.68 |
| CCS 106 Cardiac dysrhythmias | 0.56 | 0.52 | 0.61 | 0.57 | 0.50 | 0.66 |
| CCS 205 Spondylosis | 1.15 | 1.08 | 1.23 | 1.41 | 1.26 | 1.56 |
| CCS 149 Biliary tract disease | 0.88 | 0.82 | 0.95 | 0.85 | 0.74 | 0.99 |
| CCS 142 Appendicitis | 0.44 | 0.39 | 0.50 | 0.44 | 0.35 | 0.56 |
| CCS 160 Calculus of urinary tract | 0.60 | 0.54 | 0.67 | 0.50 | 0.40 | 0.63 |
| Hospital characteristics | ||||||
| Nonteaching | 1.17 | 0.98 | 1.40 | 1.27 | 1.04 | 1.54 |
| Hospital location (relative to large metro) | ||||||
| Small metro (pop. under 200,000) | 1.13 | 0.95 | 1.34 | 1.27 | 1.05 | 1.54 |
| Nonmetro | 0.57 | 0.47 | 0.69 | 0.50 | 0.39 | 0.62 |
| Hospital ownership (relative to public) | ||||||
| Not-for-profit | 1.16 | 1.00 | 1.35 | 1.23 | 1.02 | 1.49 |
| For-profit | 0.69 | 0.56 | 0.86 | 0.71 | 0.54 | 0.93 |
| Hospital bed size (relative to large hospital) | ||||||
| Small hospital | 0.78 | 0.65 | 0.93 | 0.73 | 0.59 | 0.91 |
| Medium hospital | 0.94 | 0.81 | 1.10 | 0.93 | 0.78 | 1.11 |
| Critical access hospital | 0.48 | 0.40 | 0.57 | 0.42 | 0.33 | 0.54 |
| HHI (Higher HHI -> more concentration) | 1.12 | 0.86 | 1.45 | 0.95 | 0.70 | 1.30 |
| OS ratio (medium use [12–17%] ref) | ||||||
| Low use (ratio 0–11%) | 0.84 | 0.72 | 0.98 | 0.98 | 0.81 | 1.18 |
| High use (ratio 18% or higher) | 0.92 | 0.79 | 1.08 | 0.94 | 0.77 | 1.14 |
CCS, Clinical Classification Software; HHI, Herfindahl-Hirschmann Index; OS, observation services.