correlational

Taking 3 grams of glycine before bed might make people who have trouble sleeping feel like they slept better.

Scientific Claim

Ingestion of 3 grams of glycine before bedtime is associated with improved subjective sleep quality in individuals with chronic unsatisfactory sleep, as measured by self-reported sleep satisfaction.

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 design (individual cohort) cannot establish causation, but the abstract uses 'improved' which implies causation. The correct verb strength should be 'associated with' rather than 'improved'.

More Accurate Statement

Ingestion of 3 grams of glycine before bedtime is associated with self-reported improved sleep quality in individuals with chronic unsatisfactory sleep.

Evidence from Studies

No evidence studies found yet.