Assessment of sleep duration and cortisol levels among selected South African medical students.
Mhlana A; Milanes-Rodriguez G; Olojede SO; Jegede AI · 2026 · BMC endocrine disorders
WASTE classifies this as Negative / Null Result Report · AI classification, approximate
The study found no significant effect — useful as a negative control or null benchmark for your own design.
Abstract (excerpt)
Background Sleep is essential for maintaining the body's balance, particularly in regulating the Hypothalamic-pituitary-adrenal (HPA) axis, which controls cortisol, the main stress hormone. Cortisol follows a daily rhythm, but irregular…
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Metadata source: Europe PMC · DOI 10.1186/s12902-026-02266-2