Mouth tape
Tape you wear over your mouth while you sleep. Testers get it free and cover $6.95 shipping.
- Joining
- Next group
- Starts in
- You get
- Free tape
- You pay
- $6.95 shipping
Evident Health owns Sleep Karma, the tape in this study.
Real product studies you run at home
Test The Hype On Yourself.
Now testingMouth tapeNext group starts in
A trial with one person in it. You.
- Night 1No tape
- Night 2Tape
- Night 3Tape
- Night 4No tape
- Night 5No tape
- Night 6Tape
- ThenYour answer
Same few taps every morning. Your nights with it and without it, side by side.
- Testers in Study 01, published
- 29
- Nights with dry mouth, without tape vs. with (Study 01)
- 59% → 12%
- To check in each morning
- ~1 min
Study 01: 29 testers, 81 nightly logs. Self-reported, not a clinical trial. See the results
Reviews are vibes. This is receipts.
Example reviews
- Life-changing. I sleep like a baby now!!★★★★★
- Did absolutely nothing for me.★★★★★
- Maybe it helped? Hard to say.★★★★★
Illustration · one made-up tester
2.6 → 3.8
Without2.6
With the product3.8
Sleep quality, 1–5. Same person, same questions. Not a real result: self-reported answers, not a clinical trial.
Studies One product at a time
Four steps.
No app, no account, no lab. See every step, with the real screens →
- 01
Sign up. Two minutes.
- 02
Your box arrives. The product is free.
- 03
Use it some days. Skip it on others.
- 04
Get your answer. Yours, side by side.
Questions Before you're in
What does it cost?
It depends on the study, and each one says up front. In the mouth tape study the tape is free and you pay $6.95 shipping.
Does every study pay?
No. Some only ask you to cover shipping. When a study does pay, payment never depends on what you say.
What kinds of products?
Sleep is where N of 1 started. Studies can also cover supplements, skincare and devices. Testers hear first when a new one opens.
Do I need an app or an account?
No. Every email has your own link. Tap it and your check-in opens.
What happens when my kit arrives?
Night 0 takes about 2 minutes: a 10-second skin patch test, a nose-breathing check, and a quick plan for tonight.
How long does it take?
6 nights in a row, with a check-in each morning that takes about a minute. You wear the tape on 3 of the nights and skip it on the other 3, in an order we set so the comparison is fair.
Do I need a sleep tracker?
No. If you wear one, you can add its sleep score at the end of each check-in, but it's optional.
What if I miss a night?
No problem. You make it up at the end with the same kind of night, so your comparison stays fair.
Do I need a sleep tracker?
No. If you have one (Oura, Apple Watch, Whoop, Garmin, Fitbit, Samsung or another), you can add its sleep score. It's optional.
Who can join?
Adults 18 and over. Every study starts with a short safety check, and if a study isn't a safe fit for you, it tells you before you pay anything. The full list for each study is on How it works.
What happens to my answers?
At sign-up you agree that your answers can be used anonymously. Results are observational and self-reported.
Do I have to say nice things about it?
No. Nothing you say changes what you get. “It did nothing” is a real answer, and a useful one.
Can I stop partway?
Yes, any time, and you keep the product. Reply to any email, or tap “Something’s wrong?” on your study page.
Who runs N of 1?
Evident Health, the company behind Evident Reviews. When a study tests a product from one of its own brands, the study page says so.
Is this medical care?
No. Studies are observational and self-reported, and they don’t diagnose or treat anything. The safety check screens out people a study isn’t right for.
Study 01 results are published: 29 testers, February to June 2026. See what it found →
Mouth tape study · Next group
Claim your spot. #002 is open.
Group starts in
Claim spot #002 →Free tape · $6.95 shipping
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- You
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