correlational
Taking 3 grams of glycine before bed might help people feel less sleepy during the day, according to their self-reports
Scientific Claim
Glycine ingestion (3 g) before bedtime is associated with reduced daytime sleepiness in individuals with chronic sleep dissatisfaction, as measured by the Stanford Sleepiness Scale
Original Statement
“Glycine lessened daytime sleepiness and improved performance of memory recognition tasks.”
Evidence Quality Assessment
Claim Status
overstated
Study Design Support
Design supports claim
Appropriate Language Strength
association
Can only show association/correlation
Assessment Explanation
The study uses definitive language ('lessened') but is an observational cohort study without confirmed randomization or control group, so causation cannot be established. The verb should reflect association rather than causation.
Evidence from Studies
No evidence studies found yet.