Table 1. | PICOS table |
| Component | Description |
|---|---|
| Population | Clinical patient studies that evaluate the effect of specific head posture on the volume of the upper airway. |
| Intervention | Altered head position/inclination. |
| Comparison | Valid numerical measurement of the airway volume. |
| Outcome | Changes in the head position and airway volume. |
| Study design | Randomized and non-randomized controlled trials, and cohort studies. No restriction. |
.png)
.png)
.png)
.png)