Challen et al developed models for evaluating patients in the Emergency Department (ED). One model predicts the potential for benefit from a time-critical intervention. The authors are from the University of Sheffield.
Patient selection: patient in the ED
Outcome: benefit from a time-critical intervention
Parameters:
(1) pulse in beats per minute
(2) systolic blood pressure in mm Hg
(3) Glasgow Coma Score (GCS)
Parameter |
Finding |
Points |
pulse |
<= 70 |
0 |
|
71 to 110 |
2.373 |
|
> 110 |
9.533 |
systolic blood pressure |
> 180 mm Hg |
2.888 |
|
121 to 180 |
0 |
|
100 to 120 |
1.488 |
|
< 100 |
3.614 |
GCS |
13 to 15 |
0 |
|
9 to 12 |
2.770 |
|
3 to 8 |
13.28 |
X =
= SUM(points for all 3 parameters)
probability of a potential to benefit =
= 1 / (1 + EXP((-1) * X))
Interpretation:
• The minimum value of X is 0 which occurs when all of the findings are normal. This gives a probability of 50%.
• The maximum value of X is 26.417 which has a probability of 100%.
• Although there is no factor mentioned in the text, many logistic regression models subtract a constant.
Performance:
• The area under the ROC curve was 0.74 in the derivation set and 0.71 in the validation set.
Specialty: Surgery, orthopedic, Emergency Medicine, Critical Care, Surgery, general