Table 3. Comparisons of stress scores and sleep quality across time within each group.

Variables	Control group (n=13)			Experiment group (n=13)
	Baseline	After 2 weeks of	After 4 weeks of	Baseline	After 2 weeks of	After 4 weeks of
	assessment	the scent inhalation	the scent inhalation	assessment	the scent inhalation	the scent inhalation
SPST-20	31.2 ± 7.0	31.6 ± 7.2	32.8 ± 7.8a, b	33.1 ± 7.9	32.3 ± 7.7 b	29.7 ± 7.2b, c
Thai-PQSI	4.9 ± 0.7	4.9 ± 0.9	5.3 ± 1.2	5.38 ± 0.7	5.2 ± 0.7	4.2 ± 0.8b, c

^ap<0.05: comparison with the value on after 2 weeks of the scent inhalation.

^bp<0.01: comparison with the value on baseline assessment.

^cp<0.01: comparison with the value on after 2 weeks of the scent inhalation.

SPST-20: Suanprung Stress Test-20; Thai-PQSI: Thai version of the Pittsburgh Sleep Quality Index.