Fig 1.
Logical tree representing the rules used for determining the global score SHRO’s range.
The latter depends on the ranges of the heart score SH, the respiratory score SR, and the SpO2 score SO.
Fig 2.
Boundaries of normal, abnormal, and critical value ranges for heart rate (HR), respiratory rate (RR), and blood oxygenation (SpO2).
Table 1.
Parameters a and b computed following a sigmoid model for the intermediate score functions of heart rate SH(xH), respiratory rate SR(xR), and SpO2 SO(xO).
Fig 3.
Intermediate score functions of heart rate SH(xH), respiratory rate SR(xR), and SpO2 SO(xO) obtained using a sigmoid model.
The boundary conditions have been defined thanks to the survey conducted among expert health professionals.
Table 2.
Relationship between the merging function’s output interval and the input code array’s maximum, sum range (sumMIN and sumMAX), and the number of possible subintervals NSI for n physiological parameters.
Table 3.
Merging function’s subintervals lower and upper bounds in the case of three physiological parameters (n = 3).
Fig 4.
3D plot of fmerge in the case of two input physiological parameters S1 and S2 (n = 2).
Fig 5.
Repartition of the constituted database subjects’ heart rate (HR), respiratory rate (RR) and SpO2, as well as intermediate scores SH, SR and SO respectively associated to the physiological parameters.
Fig 6.
Boxplots of score computed with 1,2 or 3 physiological parameters (among HR, RR and SpO2) represented for each group of subjects evaluated as green, orange or red by physicians.
Table 4.
Prediction success rates using 1, 2, or 3 physiological parameters (among heart rate, respiratory rate and SpO2) across the 62 non-neurological subjects, the 22 neurological subjects, and the entire database.
Fig 7.
Confusion matrix of colour code prediction using the new scoring system compared to the colour evaluation carried out by physicians as the true class for all subject (A) and for non-neurological subjects (B).
0: green, 1: orange, 2: red.
Fig 8.
Calibration curve: predicted scores using SHRO as a function of the scores evaluated by physicians.
Fig 9.
Evolution over time of two subjects A and B’s heart rate, respiratory rate, SpO2 and the associated intermediate scores SH(HR), SR(RR), SO(SpO2), as well as of the global score SHRO(HR, RR, SpO2).
The physiological parameters P and the scores SP(xP) are represented respectively with blue dots and continuous black line. The scores SH, SR, SO and SHRO have been smoothed over the equivalent of respectively 30, 60, 30 and 30 seconds.