Final multivariable models of hospitalisation of patients at the ED
| Predictor | <70 years | ≥70 years | ||
| OR | 95% CI | OR | 95% CI | |
| Age/10 | 1.25 | 1.19 to 1.30 | ||
| Sex | ||||
| Male | 1.25 | 1.11 to 1.42 | ||
| Female | Ref | Ref | ||
| Triage category | ||||
| >1 hour | Ref | Ref | Ref | Ref |
| <1 hour | 2.22 | 1.85 to 2.67 | 1.72 | 1.27 to 2.33 |
| <10 min | 3.64 | 2.93 to 4.52 | 3.15 | 2.19 to 4.53 |
| Arrival mode | ||||
| Self-referral | Ref | Ref | Ref | Ref |
| Referred | 1.21 | 1.05 to 1.40 | 1.09 | 0.82 to 1.44 |
| Ambulance | 1.94 | 1.63 to 2.32 | 1.40 | 1.03 to 1.90 |
| Chief complaint | ||||
| Minor trauma | Ref | Ref | Ref | Ref |
| Major trauma | 1.31 | 0.89 to 1.94 | 0.90 | 0.39 to 2.08 |
| Chest pain | 0.28 | 0.21 to 0.36 | 0.19 | 0.13 to 0.29 |
| Dyspnoea | 0.79 | 0.58 to 1.07 | 0.44 | 0.28 to 0.68 |
| Syncope | 0.74 | 0.51 to 1.06 | 0.52 | 0.32 to 0.83 |
| Psychiatric | 1.48 | 1.03 to 2.13 | 1.29 | 0.59 to 2.84 |
| Malaise | 1.31 | 1.03 to 1.66 | 1.27 | 0.90 to 1.78 |
| Abdominal pain | 1.34 | 1.07 to 1.68 | 1.11 | 0.74 to 1.66 |
| Other | 1.13 | 0.89 to 1.43 | 1.23 | 0.80 to 1.88 |
| Type of specialist | ||||
| Medicine | 1.17 | 0.99 to 1.37 | ||
| Surgery | Ref | Ref | ||
| Revisit to the ED | 1.57 | 1.32 to 1.88 | 1.94 | 1.41 to 2.67 |
| Phlebotomised blood sample | 4.79 | 3.83 to 5.99 | 7.46 | 4.94 to 11.28 |
| Oxygen saturation | ||||
| <90% | 1.80 | 0.93 to 3.48 | 4.26 | 1.77 to 10.25 |
| 91%–94% | 1.78 | 1.26 to 2.51 | 1.62 | 1.04 to 2.52 |
| >95% | Ref | Ref | Ref | Ref |
| Missing | 1.11 | 0.81 to 1.52 | 1.14 | 0.67 to 1.92 |
| Systolic BP | ||||
| <100 | 1.96 | 1.33 to 2.88 | 1.67 | 0.91 to 3.06 |
| 101–199 | Ref | Ref | Ref | Ref |
| >200 | 1.32 | 0.70 to 2.47 | 0.74 | 0.41 to 1.32 |
| Missing | 0.57 | 0.40 to 0.82 | 0.52 | 0.30 to 0.89 |
| Temperature | ||||
| <35.0 | 1.86 | 0.89 to 3.87 | 0.96 | 0.36 to 2.56 |
| 35.1–38.4 | Ref | Ref | Ref | Ref |
| >38.5 | 3.34 | 2.41 to 4.61 | 3.43 | 1.82 to 6.47 |
| Missing | 0.85 | 0.70 to 1.02 | 0.93 | 0.69 to 1.25 |
| Heart rate | ||||
| <50 | 0.67 | 0.36 to 1.26 | ||
| 51–100 | Ref | Ref | ||
| 101–110 | 1.62 | 1.29 to 2.03 | ||
| 111–129 | 1.57 | 1.22 to 2.02 | ||
| >130 | 2.57 | 1.76 to 3.74 | ||
| Missing | 1.07 | 0.69 to 1.68 | ||
| Respiratory rate | ||||
| <8 | 0.75 | 0.15 to 3.74 | 2.37 | 0.15 to 36.95 |
| 9–14 | Ref | Ref | Ref | Ref |
| 15–20 | 0.94 | 0.76 to 1.15 | 1.04 | 0.74 to 1.45 |
| 21–29 | 1.29 | 0.99 to 1.69 | 1.74 | 1.16 to 2.62 |
| >30 | 3.98 | 1.99 to 7.95 | 4.41 | 1.86 to 10.43 |
| Missing | 1.05 | 0.85 to 1.29 | 0.99 | 0.69 to 1.42 |
| Intercept | −4.572 | −2.623 | ||
| AUC (95% CI) | 0.85 (0.84–0.86) | 0.81 (0.79–0.82) | ||
| GoF value | 0.289 | 0.559 | ||
| Temporal validation AUC (95% CI) | 0.86 (0.85–0.87) | 0.77 (0.75–0.79) | ||
-Age in years divided by 10.
-Vital parameters measured are oxygen saturation, measured in percentage oxygenated haemoglobin; systolic BP, measured in millimetres of mercury; temperature, measured in °C; Heart rate and respiratory rate, measured as times per minute.
-p Values are derived from multiple logistic regression analysis.
-Individual chance of hospital admission <70 years=1/(1 + exp(− (−4.572 + (0.220 ∗ age/10) + 0.225 ∗ male + 0.798 ∗ triage <1 hour + 1.292 ∗ triage <10 min + 0.194 ∗ self − referral + 0.664 ∗ ambulance + 0.273 ∗major trauma + −1.282 ∗ chestpain + −0.238 ∗breathlessness + −0.305 ∗ syncope + 0.391 ∗ psychiatric + 0.269 ∗malaise + 0.294 ∗ abdominal pain + 0.122 ∗ other complaint + 0.155 medicine + 0.453 ∗ revisit + 1.567 ∗ blood drawn + 0.585 ∗ sat ≤90% + 0.576 ∗ sat 91 − 94% + 0.103 ∗ missing sat + 0.674 ∗ BP ≤100 + 0.277 BP≥200 + −0.558 ∗ BP missing + 0.619 ∗ temp ≤35 + 1.205 ∗ temp ≥38.5 + −0.165 ∗ temp missing + −0.395 ∗ heartrate ≤50 + 0.481 heartrate 101–110 + 0.450 ∗ heartrate 111–129 + 0.943 ∗ heartrate ≥130 + 0.071 ∗ heartrate missing + −0.290 ∗ resp rate ≤8 + −0.064 * resp rate 15–20 + 0.256 ∗ resp rate 21–29 + 1.380 ∗ resp rate ≥30 + 0.047 ∗ resp rate missing))).
-Individual chance of hospital admission ≥70 years=1/(1 + exp(−(−2.623 + 0.541 ∗ triage <1 hour + 1.148 triage<10 min + 0.086 ∗ self − referral + 0.337 ∗ ambulance + −0.103 ∗ major trauma + −1.640 ∗ chestpain + −0.829 ∗ breathlessness + −0.659 ∗ syncope + 0.258 ∗ psychiatric + 0.236 ∗malaise + 0.102 ∗ abdominal pain + 0.208 ∗ other complaint + 0.663 ∗ revisit +2.010 ∗ blood drawn + 1.449 ∗ sat ≤90% + 0.483 ∗ sat91 − 94% + 0.128 ∗ missing sat + 0.511 ∗ BP ≤100 + −0.300 ∗ BP ≥200 + −0.655 ∗ BP missing + − 0.037 ∗ temp ≤35 + 1.232 ∗ temp ≥38.5 + −0.071 ∗ temp missing + 0.861 ∗ resp rate ≤8 + 0.037 ∗ resp rate 15–20 + 0.555 ∗ resp rate 21–29 + 1.483 ∗ resp rate ≥ 30 + −0.014 ∗ resp rate missing))).
-AUC, area under the curve; GoF, Hosmer-Lemeshow goodness-of-fit χ2 test.