Table 4.

Clinical Relevance Based on 0.5 SD Difference Criterion for the Intervention Group

Outcome	0.5 SD Pre-Test Mean	Difference Between Pre- and Post-Test Means*	Clinically Significant? (Difference ≥ 0.5 SD?)
Sleep quality (PSQI)	1.6	2.7	Yes
Sleep duration (h)**	0.6	0.6	Yes
Insomnia symptoms (ISI)	2.3	3.6	Yes
Sleep behaviors (SHI)	4.2	4.2	Yes
Daytime sleepiness (ESS)	2.9	0.7	No

Notes: Data presented are means ± SD. PSQI (Pittsburgh Sleep Quality Index) measures perceived sleep quality over the past month; higher values indicate worse sleep quality. *Absolute values. **Sleep duration (h) was extracted from the PSQI. ISI (Insomnia Severity Index) measures perceived insomnia symptoms over the past two weeks. SHI (Sleep Hygiene Index) measures the frequency of engaging in behaviors that do not support sleep. ESS (Epworth Sleepiness Scale) measures recent likelihood of excessive daytime sleepiness.