CHAMGAP
APPROVEDReviewed and approved by the Chamgap Editorial Team (2026-08-14). The draft was written by AI, the existence of all 2 cited sources was verified at the original page, and the verdict passed blind grading and adversarial audit. Methodology v0.7.
Verdict No. 2568 · Search date 2026-08-14 · Methodology v0.7

Provent nasal EPAP,
does it really help with Reduced apnea-hypopnea index versus a sham valve in obstructive sleep apnea?

30-Second Summary
C
Evidence Grade C · 50 · Safety caution
Provent lowered AHI in a manufacturer-funded trial, while an independent trial in another clinical setting was null.
Nasal discomfort, skin irritation, dry mouth, and breathing discomfort can occur; 7% discontinued the pivotal trial because of device-related events. Sleep-specialist review is needed for severe cardiopulmonary disease, nasal obstruction, or any attempt to replace CPAP.
What the
research shows
The grade is C. In a 250-participant manufacturer-funded trial, the three-month analysis included 100 versus 95 and median AHI reduction was 42.7% versus 10.1% (P<.0001). Prespecified success, at least 50% reduction or AHI below 10, occurred in 50.7% versus 22.4% (P=.001). AHI is a surrogate, only 195 of 250 remained in the three-month analysis, and an independent CPAP-withdrawal trial was null in a different population; this gives C with 50 points.
What the
ads claim
The valve genuinely creates greater expiratory than inspiratory resistance. A lower AHI does not establish prevention of cardiovascular events or symptom and safety equivalence to CPAP.
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Useful facts when choosing a product

  • Provent is a disposable mechanical resistance valve adhered over both nostrils.
  • Berry tested nightly use for three months against a similar low-resistance sham.
  • Current official Korean availability of the original Provent product was not confirmed.
Gap Measurement · Verdict 2568 · C 50
What advertising claims
What independent, higher-quality research supports
△ GAP
01

What the research actually shows

Berry RB, Kryger MH, Massie CA randomized 127 versus 123; week-one analysis included 119 versus 110 and three-month AHI analysis 100 versus 95. The primary endpoint was the between-group comparison of device-on versus device-off AHI at week one; three-month AHI was secondary. The paper states, “This study was funded by Ventus Medical, Inc.” Rossi VA, Winter B, Rahman NM, Yu LM et al. randomized 67 established CPAP users among continued CPAP, Provent, and sham Provent, analyzing 63 per protocol. The studies differed in population and treatment context and were not counted as direct replication.

02

Why this is classified as C (50)

A substantial surrogate response in a manufacturer-funded trial, 22% missing from three-month analysis, and an independent null trial in a different clinical context give C with 50 points.

Counterpoint. Some patients clearly responded, but predictors of response were not identified and CPAP substitution was not established.

Rejudgment record. Cross-check applied — We cross-checked populations, analysis denominators, prespecified outcomes, AHI results, allocation method, funding, and registration in both primary reports.

Scoring profile behind this grade
EndpointSSurrogate marker - laboratory or imaging measures
ReplicationR1Single confirmatory trial
IndependenceI1Mixed funding sources
Effect sizeE+Meets the clinically important threshold

The scoring table and the verdict agree (C).

Sub-claim grades by effect

This ingredient is marketed for several effects. A single overall grade blends strong and weak claims together, so each effect is graded separately here. The overall grade reflects the strongest disconfirming or core claim.

Effect (sub-claim)GradeBasis
Reduced three-month AHI in previously untreated OSACThe manufacturer-funded trial was positive, with a surrogate endpoint and missing data.
Short-term replacement for CPAPDThe CPAP-withdrawal trial found no difference from sham.

Cross-check — Codex and Claude

This verdict was drafted by Codex through literature review and source-existence checks, cross-checked through blind grading and adversarial audit, and settled by reapplying the methodology boundary rules. Cases with split grades were resolved through rejudgment.
03

Evidence Table

StudyDesignSampleFundingEndpointResultWeight
Berry RB, Kryger MH, Massie CA, 2011Nineteen-center randomized double-blind sham-controlled trial95Ventus Medical, Inc.Week-one between-group AHI difference as primary; three-month AHI as secondaryMedian three-month AHI reduction 42.7% versus 10.1%, P<.0001; success 50.7% versus 22.4%, P=.001Manufacturer-funded positive surrogate trial
Study 2Three-arm partially blinded randomized placebo-controlled CPAP-withdrawal trial63Registry sponsor University of Zurich; article funding statement not verifiedAHI, ODI, and ESS at two weeksProvent versus sham Provent AHI difference +3.2 events/hour (95% CI −7.7 to 14.1), P=.52Independent null trial in a different clinical setting
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Receipt — 2 References

All 2 cited sources were verified for existence at the original page (as of 2026-08-14).

Berry RB, Kryger MH, Massie CA. A Novel Nasal Expiratory Positive Airway Pressure (EPAP) Device for the Treatment of Obstructive Sleep Apnea: A Randomized Controlled Trial. Sleep. 2011;34(4):479-485. PMID: 21461326. DOI: 10.1093/sleep/34.4.479. NCT00772044.
checked
Rossi VA, Winter B, Rahman NM, Yu LM, et al. The effects of Provent on moderate to severe obstructive sleep apnoea during continuous positive airway pressure therapy withdrawal. Thorax. 2013;68(9):854-859. PMID: 23723343. DOI: 10.1136/thoraxjnl-2013-203508. NCT01332175.
checked
Draft and rewrite: Codex (AI) · Verification: Codex blind grading and adversarial audit · Final adjudication: Claude
Reviewed and approved: Chamgap Editorial Team · Approval date: 2026-08-14 · Corrections: none

Cite this verdict

Provent nasal EPAP x reduced AHI in obstructive sleep apnea Evidence Grade C card
[Chamgap] Provent nasal EPAP x reduced AHI in obstructive sleep apnea — Evidence Grade C·50. 2 cited sources checked. Source: https://chamgap.com/en/verdicts/sleep/provent-nasal-epap-obstructive-sleep-apnea-ahi/ · CC BY 4.0

CC BY 4.0 — free to use with attribution; do not distort grades, numbers, or verdict meaning.

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What this document does and does not do

Chamgap is an information source. It reports what research has and has not confirmed; it does not tell readers what to take or buy. That decision belongs to readers and, when needed, medical or legal professionals. This verdict reflects literature available up to the search date and may change as new research appears. Nothing here is medical advice.