Evidence map›Paper›PMID 35675229›Full record

Trial reportPloS one2022

Probiotics for Reduction of Examination Stress in Students (PRESS) study: A randomized, double-blind, placebo-controlled trial of the probiotic Lacticaseibacillus rhamnosus HN001.

Rebecca F Slykerman, Eileen Li, Edwin A Mitchell

Open access · goldAbstract readRandomized Controlled Trial
In one paragraph

Trial report in PloS one, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 6 papers, 1 of them a synthesis that pooled it.

0numbers the graph read from it
0cells of the map it votes in
6citing papers in PubMed, 1 pooled it
0.8field-weighted citation impact, top 31% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

6 citing papers in PubMed, 1 synthesis or guideline pooled it, 9 citations in OpenAlex.

  1. Pooled it
  2. Article
  3. Frontiers in physiology · 2026
    Article
  4. Article
  5. Article
  6. The therapeutic effects ofGut microbiome (Cambridge, England) · 2025
    Review
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

3 authors at 1 institution in 1 country.

Rebecca F SlykermanDepartment of Psychological Medicine, University of Auckland, Auckland, New Zealand.ORCID 0000-0003-4942-8887
Eileen LiA Better Start - National Science Challenge University of Auckland, New Zealand.ORCID 0000-0001-8251-4942
Edwin A MitchellDepartment of Pediatrics, Child & Youth Health, University of Auckland, New Zealand.ORCID 0000-0001-6187-7648
University of Auckland · NZ

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundStudies suggest that bioactive compounds such as probiotics may positively influence psychological health. This study aimed to determine whether supplementation with the probiotic Lacticaseibacillus rhamnosus HN001 reduced stress and improve psychological wellbeing in university students sitting examinations.

methodsIn this randomized, double-blind, placebo-controlled study, 483 undergraduate students received either the probiotic L. rhamnosus HN001, or placebo, daily during a university semester. Students completed measures of stress, anxiety, and psychological wellbeing at baseline and post-intervention before examinations. Mann Whitney U tests compared the change in psychological outcomes between groups.

resultsOf the 483 students, 391 (81.0%) completed the post-intervention questions. There was no significant difference between the probiotic and placebo supplemented groups in psychological health outcomes. The COVID19 pandemic restrictions may have influenced the typical trajectory of stress leading up to examinations.

conclusionWe found no evidence of significant benefit of probiotics on the psychological health of university students. These findings highlight the challenges of conducting probiotic trials in human populations where the potential for contextual factors such as COVID19 response, and participant adherence to the intervention may influence results.

Indexed as

COVID-19Lacticaseibacillus rhamnosusProbioticsDietary SupplementsDouble-Blind MethodHumansStudents

Identifiers

PMID35675229
PMCPMC9176810
OpenAlexW4285412562

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.