Free. No account needed.
Health questions, answered from real studies
Ask in plain English. Every result is ranked by our custom Research Evidence Rank (RER): study design, sample size, and relevance, scored 0–100.
Synapse summarizes published research for learning. It is not medical advice. Talk to a doctor about your own health decisions.
How it works
Research Evidence Rank (RER)
I built a custom ranking algorithm for Synapse, not a generic LLM score. Every paper gets a transparent 0–100 evidence score from PubMed metadata and abstract text alone. It runs in under a millisecond on every search, sorts results strongest-evidence-first, and powers the overview verdict.
Study design
34%Meta-analysis and RCTs rank above case reports, modeled on GRADE / Oxford CEBM levels.
Sample size
16%Parsed from abstracts (n=…); larger trials score higher on a log curve.
Query relevance
16%BM25-lite match between your question and title + abstract.
Recency
12%Newer publications score higher; missing dates get a neutral default.
Rigor flags
14%Blinding, placebo control, preregistration, minus conflicts or tiny samples.
Journal tier
8%High-impact venues (Lancet, NEJM, JAMA, Cochrane, etc.) get a boost.
Study design ladder (strongest → weakest)
- 1.Network meta-analysis
- 2.Meta-analysis / systematic review
- 3.Randomized trial (RCT)
- 4.Clinical trial
- 5.Cohort
- 6.Case-control
- 7.Observational
- 8.Case report
- 9.Preclinical
- Deterministic
- Same paper, same score. Reproducible and auditable.
- No LLM for ranking
- Regex + heuristics only; AI is separate for summaries and Q&A.
- After deep analysis
- A second custom scorer refines the number once a paper is fully analyzed.