Home /
Sourcing standards
This page is a reference summary of published evidence and regulatory documents. It is not a substitute for individual medical advice, and it is not a recommendation to take or avoid any medicine.
Medically reviewed by Dr. Sofia Lindqvist, · Last reviewed 11 August 2026
Every claim on NootropicsDaily is sourced according to a fixed hierarchy, from regulatory documents at the top down to expert guidance. This page states that hierarchy, what counts as unacceptable evidence, and the writing rules — citation, uncertainty, effect size — that follow from it.
On this page
Source hierarchy
| Rank | Source type | Why it ranks here |
|---|---|---|
| 1 | Regulatory documents and approved labels | Reflects a regulator's full-dataset review; the authoritative current position on dosing, indication and safety. |
| 2 | Systematic reviews and meta-analyses | Pools multiple trials, reducing the influence of any single study's bias or small sample. |
| 3 | Randomised controlled trials | Controls for confounding directly; the strongest single-study design for effect claims. |
| 4 | Observational and registry data | Useful for rare outcomes, real-world populations and pregnancy/long-term signals trials cannot capture. |
| 5 | Pharmacology reference texts | Reliable for mechanism, kinetics, and receptor-level detail not always restated in trial papers. |
| 6 | Expert guidance and consensus statements | Useful where trial evidence is sparse, but represents opinion rather than primary data. |
Higher-ranked sources take precedence when sources conflict.
Not acceptable as evidence
Excluded sources
Vendor or manufacturer marketing copy, forum or community posts used as evidence of a drug’s effect, and secondary news reporting cited without the underlying study, are not acceptable as sources for a factual claim on this site.
How to cite
Every clinical or regulatory claim needs a citation resolvable to a specific document: a label, a trial registry entry, a DOI, or a named regulatory communication with a date. A citation to “research shows” without a resolvable source is treated as an unsupported claim and removed.
When to state uncertainty
If a question has not been directly studied, or has been studied only in a small or indirect way, the page says so plainly — “this has not been systematically studied” is itself information, not a gap to paper over with a plausible-sounding guess.
How to report effect sizes
State the actual number from the source — a pooled standardised mean difference, an odds ratio, a percentage change in AUC — with a brief plain-language size label (small, moderate, large) rather than a bare verdict like “effective” or “not effective.” Readers should be able to judge the magnitude themselves.
What is the top source tier?
Regulatory documents and approved product labels — FDA, EMA, MHRA and equivalent national regulators — because they reflect the reviewed, current position of an authority with access to the full dataset.
Is a forum post ever used as a source?
Not as evidence of a drug’s effect. Forum and community reports may occasionally be referenced to describe how a topic is discussed publicly, but never to support a claim about efficacy, safety, or mechanism.
How is uncertainty written into a page?
As a direct statement of fact — for example, ‘this has not been systematically studied’ — rather than as a hedge or a vague qualifier.
How are effect sizes reported?
With the actual number and its context, such as a pooled standardised mean difference and a plain-language size label, rather than a verdict like ‘effective’ or ‘not effective.’
Can news coverage of a study be cited?
Only alongside the underlying study itself, never as the sole source. Secondary reporting without the underlying paper is not acceptable as a citation.