Table 2.

Scoring threshold values of new national maternity early warning score (MEWS) for each vital sign

Vital signs	Score
	2 points	1 point	0 points	1 points	2 points
Respiratory rate (breaths/min)	≤6	7-8	9-21	22-24	≥25
Oxygen saturation (%)	≤92	93-94	≥95	—	—
Temperature (°C)	≤34.8	34.9-35.5	35.6-37.2	37.3-37.5	≥37.6
Pulse rate (beats/min)	≤62	63-70	71-112	113-121	≥122
Systolic blood pressure (mm Hg)	≤93	94-100	101-135	136-144	≥145
Diastolic blood pressure (mm Hg)	≤56	57-61	62-88	89-96	≥97

Each vital sign was scored independently, and was scored 0, 1, or 2 points. Non-zero (ie, 1 or 2) points can be scored for vital signs that are either high or low, except for oxygen saturation, which only scored for low values (therefore, all values ≥95% scored 0 points). Individual points were summed to calculate a total early warning score. Because each vital sign can score between 0 and 2 points, the total score can range from 0 to 12.

Example: if a woman's respiratory rate was 22 breaths/min, oxygen saturation 96%, temperature 34.7°C, pulse rate 116 beats/min, systolic blood pressure 139 mm Hg, and diastolic blood pressure 102 mm Hg, she would score 1 point for respiratory rate (22-24 range), 0 points for oxygen saturation (≥95% range), 1 point for temperature (34.9-35.5 range), 1 point for pulse rate (113-121 range), 1 point for systolic blood pressure (136-144 range), and 2 points for diastolic blood pressure (≥97 range). The total (MEWS) score would be 6 points (1+0+1+1+1+2).