correlational

Taking 3 grams of glycine before bed might help people fall asleep faster, according to sleep monitoring equipment

Scientific Claim

Glycine ingestion (3 g) before bedtime is associated with reduced sleep onset latency as measured by polysomnography in individuals with chronic sleep dissatisfaction

Original Statement

Glycine improved subjective sleep quality and sleep efficacy (sleep time/in-bed time), and shortened PSG latency both to sleep onset and to slow wave sleep without changes in the sleep architecture.

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 ('shortened') 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.