Table 2. Comparisons of stress scores between two groups and within group before, after 2 weeks, and after 4 weeks of the scent inhalation.

Variables	Time	Control group (n=13)	Experiment group (n=13)
Stress: SPST-20 (score)	Baseline assessment	31.2 ± 7.0	33.1 ± 7.9
	After 2 weeks of the scent inhalation	31.6 ± 7.2	32.3 ± 7.7
	After 4 weeks of the scent inhalation	32.8 ± 7.8	29.7 ± 7.2
Sleep quality: Thai-PQSI (score)	Baseline assessment	4.9 ± 0.7	5.4 ± 0.7
	After 2 weeks of the scent inhalation	4.9 ± 0.9	5.2 ± 0.7
	After 4 weeks of the scent inhalation	5.3 ± 1.2	4.2 ± 0.8*

Mean ± SD, *p<0.05: comparison with the control group.

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