Tier 4 — mechanistic

Comparative effects of glycine and D-cycloserine on persistent negative symptoms in schizophrenia: a retrospective analysis

Heresco-Levy U, Javitt DC
Schizophrenia research 2004 66(2-3):89-96

Bibliography

PubMed
PMID 15061240
DOI
10.1016/s0920-9964(03)00129-4
Funding
Funding was not specified in the indexed abstract; the full funding disclosure has not been verified.
Competing interests
The accessible abstract does not establish the authors' competing interests; absence of a statement is not evidence of no conflicts.

Study snapshot

DesignHuman observational study
ModelAdult humans
Sample17 patients who had participated in trials of both agents
InterventionRetrospective within-person comparison of glycine and D-cycloserine trial responses
DurationReanalysis of prior treatment periods
EndpointsPersistent negative symptoms; Between-agent clinical response

What the study showed, in plain terms

This retrospective analysis compared responses among patients who had received both agents in earlier trials. It is a reanalysis of existing participants, not a new independent randomized cohort.

Key findings

  • The selected sample showed larger symptom changes during glycine than D-cycloserine treatment.
  • The comparison drew on participation in separate prior trials.

What this study can and cannot tell us

Retrospective selection and differences between trial periods limit causal comparison.

Do not add these seventeen patients to earlier cohort totals as independent evidence.

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Editorial review

Reviewed by the Biohack Blueprint research team

Last verified

Dr. Khaled Mahmoud, MBBChCritical Care Medicine, Longevity Science & Editorial Direction