Guides: how to check the evidence yourself

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57 guides on reading the evidence behind a discount code and a lab report, each one showing our own record rather than describing one. Updated October 11, 2026.

Where a discount code is actually applied, and why the stage matters

Where do you enter a discount code?

Reading a cart total line by line

How to read a cart total?

Two reductions do not add, and the difference is real money

Do two discounts add together?

What a code restriction actually looks like in a cart

Why did my discount code not work?

Checking a code yourself, in about two minutes

How do i check a discount code is real?

A claim without a date cannot be wrong, which is the problem

How recent is a verified discount code?

Reading a third-party assay report, field by field

How to read a peptide lab report?

A published set with no failures has been filtered

Are published lab results trustworthy?

Purity is composition, not effect and not dose

What does peptide purity percentage mean?

A record you can recompute, rather than one you must trust

How do you know a verification log is not edited?

The word 'verified' does almost no work on its own

What does verified mean on a coupon site?

The limits of everything published here, in one place

What are the limits of coupon verification evidence?

What an HPLC purity figure is a measurement of, and what it is not

What does hplc measure on a peptide report?

Why identity is measured by mass, and what a mass result settles

What does mass spectrometry show on a peptide test?

The known material every measurement is compared against

What is a reference standard in lab testing?

Why results differ between production runs of the same product

Why do peptide batches have different purity?

What freeze-drying does, and what it means for handling

Why are peptides shipped as powder?

What makes up the non-target fraction, and why its composition matters

What are the impurities in synthetic peptides?

Milligrams, micrograms and international units, and why they do not convert

What do mg mcg and iu mean on a peptide label?

What a certificate assumes about the sample it describes

What is chain of custody in lab testing?

The four routes a compound breaks down by, and which ones you control

How do peptides degrade in storage?

Why n matters, and what a result from a small group does and does not support

Why does sample size matter in a study?

The difference between a claim that was tested and one that was repeated

What does verified at checkout actually mean?

What a listing is asserting, and what would make it false

Why do coupon listings need evidence?

Two different activities that look identical on the page

Is finding a discount code the same as verifying it?

Deciding between two pages that say different things

How do i compare two discount code claims?

The conditions that decide whether a code works on your cart

What terms decide whether a discount code works?

Tracing a claim back to the study it came from

How do i find the study behind a peptide claim?

What a registry record tells you before any results exist

What does a clinical trial registry entry tell you?

Verifying that a source supports the sentence attached to it

How do i check if a citation supports the claim?

Reading a recall for what it establishes

How do i read a product recall notice?

The specific thing 'peer-reviewed' certifies

What does peer review actually check?

The gap between a clean certificate and a safe order

What does third party tested actually mean?

Three minutes that separate a real analysis from a letterhead

How to verify a testing lab is real?

The one field that makes a certificate checkable

What is a lot number on a certificate of analysis?

What a page is being paid to say, and how to see it

How to spot a fake review site?

Why the origin of a parcel is a practical question, not a patriotic one

Does it matter where a supplier ships from?

A record with no bad results has not been tested as a record

Should a vendor publish failed test results?

The clause that tells you what the seller expects to go wrong

What should a supplier refund policy say?

Why some codes persist for years and others die in a week

Do promo codes expire?

Forum accounts as evidence: where they are strong and where they are not

Are reddit reviews reliable?

The top of the page carries most of what can be checked

How to read a certificate of analysis?

Growth hormone is the one item in our set reported by fill rather than purity, and its number looks worse because it is a different number

How is hgh purity tested?

The most-tested item in our set is also the one with the thinnest independent literature, and those two facts are unrelated

Is there research on retatrutide?

Almost all of it is animal work, which is a specific limitation rather than a general dismissal

Is bpc 157 proven in humans?

A copper peptide whose literature is mostly topical and cosmetic, which is a different field from everything else in this index

What is ghk-cu used for in research?

It is the item in this index with a genuine approved-drug evidence base, and the contrast is instructive

Is tirzepatide approved?

A fragment of a naturally occurring protein, studied mostly in animals and explicitly prohibited in sport

Is tb-500 banned?

Approved for one narrow indication, used far outside it, and the gap between those two facts is the whole story

Is tesamorelin approved?

A mitochondrial-derived peptide from a research area barely a decade old, where almost everything is cell and animal work

Is there human research on mots-c?

The most heavily evidenced molecule in this index, which makes it the best illustration of what the others lack

How much research is there on semaglutide?

Not a peptide at all, which changes what the laboratory can tell you about it

How is nad+ tested?

A three-amino-acid fragment with a small literature, where the honest answer is that there is not much to report

Is there evidence for kpv?

The highest purity figures in our set belong to an old, well-characterised molecule, and that is not a coincidence

Why is ipamorelin so pure?

Clinical evidence exists, in a national literature most readers cannot independently verify

Is selank clinically approved?

The gap between what is claimed for it and what has been measured is wider than for almost anything else here

Does semax actually work?

An approved product exists — for one indication, one population, one dose and one route

Is pt-141 fda approved?

Related

• The evidence index
• The research record