· INDEPENDENT SKINCARE RESEARCHThe Luména Barrier Repair Serum Study
A 30-day real-world customer study conducted by BioStackr for Luména Skin.
Across 48 analysed completers, the strongest tracked skin outcomes moved in a positive direction.
- 48-hour double check-in required before product shipped
- Ensures baseline data collected before serum use began
- Pre-study check-ins establish each participant's starting point
- 5-day baseline window before product arrived
- Final 5 study days = endpoint comparison
- Days tagged at submission for: sun exposure, hormonal flare, new products, high stress, heavy makeup
- Excluded from primary analysis
- Reviewed separately as context
- Cohen's d (effect size)
- 95% confidence intervals
- Bootstrap resampling
- 56 confirmed, 48 completers, 9 countries
- 30-day single-arm cohort. Each participant served as own control
- Recruited from existing Luména Skin customer base
- Cohort size is set per brand. Larger cohorts are available where stronger statistical confidence is needed.
What participants wanted help with.
Not a first-time skincare audience.
Many participants had already tried other skincare products before the study.
That gave the study real comparison context.
Changes observed across all tracked outcomes.
Cohort outcomes across 48 analysed completers. Baseline vs final 5 days.
The clearest pattern was calmer skin alongside smoother texture and more even tone: comfort improved for 76% of analysed completers, texture for 82%, and tone for 74%.
What participants said.
Responses are shown anonymously.
My skin felt calmer within the first two weeks. The redness around my nose looked noticeably softer by day 18.
Texture was the first thing I noticed. My makeup sat better and my skin felt less tight in the mornings.
I have tried a lot of barrier products. This was the first one that felt soothing without making me greasy.
Flare-ups used to happen every few days. By the end of the study they were much less frequent and easier to manage.
Simple routine, no stinging, and my skin looked more even in photos by week three.
I stopped layering three different serums. One product, daily, and my skin finally felt balanced.
Study governance and disclosures
Study classification, independence, data handling, and limitations are set out below.
- Prospective, observational, single-arm real-world cohort.
- Within-subject design: each participant serves as their own control.
- No placebo arm, no randomisation, no blinding.
- Endpoint: final 5 study days compared against each participant's pre-product baseline.
- This study was commissioned by Luména Skin and conducted independently by BioStackr.
- BioStackr designed the protocol, managed data collection, set the confound-exclusion rules, and ran the analysis. Luména Skin had no access to raw submissions and no editorial control over metrics, exclusions, or results.
- BioStackr earns no commission, affiliate fee, or revenue from Barrier Repair Serum sales.
- Outcomes self-reported via daily structured check-ins.
- Confound-tagged days excluded from the primary analysis and reviewed separately.
- Effect sizes via Cohen's d; 95% confidence intervals from 10,000-iteration bootstrap resampling.
- Analysis limited to participants who completed the study and met the minimum check-in threshold.
- Self-reported outcomes carry recall and expectation bias.
- Without a placebo arm, results cannot isolate the product from placebo and natural variation.
- A single-cohort study is not generalisable to the whole population.
- Findings describe what these customers reported, not a clinical efficacy or treatment claim.
Factors we excluded
Participants flagged days affected by these factors. We excluded them from the primary analysis so the findings reflect normal days, then reviewed them separately.
The private brand report
What the public page does not show.
The page above is the public proof. Alongside it, your team receives a private report built from the same study, covering the things a standard user trial never surfaces:
- Why customers chose your product, in their own words
- What they used before, and what they nearly bought instead
- The objection that almost stopped them buying, and how it resolved
- The exact language customers use when the product works, ready for your product page, ads and email
- Claim angles and competitor comparisons drawn from real customer experience
- Practical recommendations for where to use it all: product pages, ads, email, retail
A user trial tells you whether customers liked the product. The private report tells you why they bought, why they almost didn't, and what to say to the next customer.