| Item | Knowledge M (SD) | Practice M (SD) | ||
|---|---|---|---|---|
| Water | 3.91 (0.84) | 3.89 (0.80) | –.166 | .868 |
| Caffeine | 3.48 (0.93) | 4.02 (0.76) | 4.963 | <.001 |
| Smoking | 4.16 (1.05) | 4.79 (0.50) | 6.778 | <.001 |
| Alcohol | 4.15 (0.87) | 4.30 (0.74) | 1.684 | .095 |
| Milk | 3.00 (1.16) | 4.49 (0.62) | 12.543 | <.001 |
| Midnight snack | 3.67 (1.11) | 4.31 (0.72) | 5.395 | <.001 |
| Overeat | 3.72 (0.95) | 3.79 (0.65) | .656 | .513 |
| Spicy food | 3.80 (0.93) | 3.75 (0.66) | –.546 | .586 |
| Sleep | 4.36 (0.73) | 3.68 (0.69) | –7.672 | <.001 |
| Cough | 3.81 (0.92) | 3.93 (0.71) | 1.145 | .255 |
| Long speaking | 4.22 (0.84) | 3.75 (0.66) | –5.014 | <.001 |
| Shouting | 4.47 (0.71) | 3.95 (0.73) | –5.923 | <.001 |
| Whisper | 3.46 (1.11) | 3.88 (0.78) | 3.658 | <.001 |
| Speak in dust | 4.27 (0.76) | 3.93 (0.66) | –4.113 | <.001 |
| Sing in dust | 4.38 (0.71) | 4.03 (0.67) | –4.036 | <.001 |
| Tight cloth | 3.10 (1.06) | 3.99 (0.74) | 7.575 | <.001 |
| Tight cloth on stage | 3.47 (1.03) | 3.96 (0.75) | 4.216 | <.001 |
| Abdominal breathing | 3.63 (0.92) | 3.81 (0.72) | 1.801 | .074 |
| Abdominal breathing in singing | 4.12 (0.91) | 4.00 (0.74) | –1.467 | .145 |
| Voice range | 4.11 (0.80) | 3.69 (0.63) | –4.898 | <.001 |
| Total | 77.29 (8.91) | 79.93 (5.30) | 3.409 | .001 |