Trial Outcomes & Findings for tAVNS for Stress Reduction in University Students (NCT NCT07411846)

NCT ID: NCT07411846

Last Updated: 2026-04-08

Results Overview

Psychological distress assessed using the 10-item Kessler Psychological Distress Scale (K10). Scored 1 ("never") to 5 ("always") with reference to the prior 30 days and summed to a total score of 10-50, with higher scores indicating higher distress.

Recruitment status

COMPLETED

Study phase

NA

Target enrollment

40 participants

Primary outcome timeframe

Baseline (pre-intervention), immediately post-intervention (after 5 daily sessions, approximately day 5), and 1-month follow-up

Results posted on

2026-04-08

Participant Flow

Participants were recruited from the Egas Moniz School of Health and Science (Almada, Portugal) via brief in-person classroom information sessions, after which interested students accessed an online enrollment link. Recruitment targeted university students with elevated psychological distress (K-10 ≥ 22).

Following online enrollment and completion of baseline assessment (sociodemographic questionnaire, PSS-10, and K-10), eligible participants were contacted by email to schedule sessions. Immediately before the first session, exclusion criteria were re-checked; no participant met exclusion criteria at that time. Randomization was performed using an online research randomizer (randomizer.org) in a 1:1 ratio after eligibility confirmation.

Participant milestones

Participant milestones
Measure
taVNS
Participants receive five consecutive daily 30-minute sessions of transcutaneous auricular vagus nerve stimulation using the Nurosym device. The electrode is positioned on the left tragus. Participants received only active taVNS during the randomized phase; no cross-over to other interventions occurred during the trial.
Sham
Participants received only sham stimulation during the randomized phase. No cross-over occurred and all analyses reflect the original randomized groups.
Overall Study
STARTED
20
20
Overall Study
COMPLETED
20
20
Overall Study
NOT COMPLETED
0
0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Race and Ethnicity were not collected from any participant.

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
taVNS
n=20 Participants
Participants receive five consecutive daily 30-minute sessions of transcutaneous auricular vagus nerve stimulation using the Nurosym device. The electrode is positioned on the left tragus.
Sham
n=20 Participants
Participants receive five consecutive daily 30-minute sessions of transcutaneous auricular vagus nerve stimulation using the Nurosym device. The electrode is positioned on the left earlobe
Total
n=40 Participants
Total of all reporting groups
Age, Continuous
20.95 Years
STANDARD_DEVIATION 2.48 • n=20 Participants
21.35 Years
STANDARD_DEVIATION 3.03 • n=20 Participants
21.15 Years
STANDARD_DEVIATION 2.74 • n=40 Participants
Sex: Female, Male
Female
17 Participants
n=20 Participants
16 Participants
n=20 Participants
33 Participants
n=40 Participants
Sex: Female, Male
Male
3 Participants
n=20 Participants
4 Participants
n=20 Participants
7 Participants
n=40 Participants
Race and Ethnicity Not Collected
0 Participants
Race and Ethnicity were not collected from any participant.
Psychological Distress at Baseline (K-10)
30.30 Scores on a scale
STANDARD_DEVIATION 4.60 • n=20 Participants
29.50 Scores on a scale
STANDARD_DEVIATION 6.29 • n=20 Participants
29.90 Scores on a scale
STANDARD_DEVIATION 5.45 • n=40 Participants
Perceived Stress at Baseline (PSS-10)
24.05 Scores on a scale
STANDARD_DEVIATION 3.82 • n=20 Participants
23.60 Scores on a scale
STANDARD_DEVIATION 4.98 • n=20 Participants
23.83 Scores on a scale
STANDARD_DEVIATION 4.4 • n=40 Participants

PRIMARY outcome

Timeframe: Baseline (pre-intervention), immediately post-intervention (after 5 daily sessions, approximately day 5), and 1-month follow-up

Psychological distress assessed using the 10-item Kessler Psychological Distress Scale (K10). Scored 1 ("never") to 5 ("always") with reference to the prior 30 days and summed to a total score of 10-50, with higher scores indicating higher distress.

Outcome measures

Outcome measures
Measure
taVNS
n=20 Participants
Participants receive five consecutive daily 30-minute sessions of transcutaneous auricular vagus nerve stimulation using the Nurosym device. The electrode is positioned on the left tragus.
Sham
n=20 Participants
Participants receive five consecutive daily 30-minute sessions of transcutaneous auricular vagus nerve stimulation using the Nurosym device. The electrode is positioned on the left earlobe
Psychological Distress (K10)
Baseline
30.30 Scores on a scale
Standard Deviation 4.60
29.5 Scores on a scale
Standard Deviation 6.29
Psychological Distress (K10)
Post-intervention
27.20 Scores on a scale
Standard Deviation 6.97
27.10 Scores on a scale
Standard Deviation 5.61
Psychological Distress (K10)
Follow-up
24.15 Scores on a scale
Standard Deviation 6.82
23.40 Scores on a scale
Standard Deviation 6.59

PRIMARY outcome

Timeframe: Baseline (pre-intervention), immediately post-intervention (after 5 daily sessions, approximately day 5), and 1-month follow-up

Perceived stress assessed using the 10-item Perceived Stress Scale (PSS-10). Scored 0 ("never") to 4 ("very often") and summed to a total score of 0-40, with higher scores indicating higher perceived stress.

Outcome measures

Outcome measures
Measure
taVNS
n=20 Participants
Participants receive five consecutive daily 30-minute sessions of transcutaneous auricular vagus nerve stimulation using the Nurosym device. The electrode is positioned on the left tragus.
Sham
n=20 Participants
Participants receive five consecutive daily 30-minute sessions of transcutaneous auricular vagus nerve stimulation using the Nurosym device. The electrode is positioned on the left earlobe
Perceived Stress (PSS-10)
Baseline
24.05 Scores on a scale
Standard Deviation 3.82
23.60 Scores on a scale
Standard Deviation 4.98
Perceived Stress (PSS-10)
Post-intervention
21.85 Scores on a scale
Standard Deviation 5.95
21.35 Scores on a scale
Standard Deviation 5.42
Perceived Stress (PSS-10)
Follow-up
19.40 Scores on a scale
Standard Deviation 6.69
18.95 Scores on a scale
Standard Deviation 6.25

PRIMARY outcome

Timeframe: From randomization through 1-month follow-up

Feasibility was assessed using retention of participants from baseline to the end of the study. For each arm, the number of randomized participants who completed all five stimulation sessions and the 1-month follow-up assessment was recorded.

Outcome measures

Outcome measures
Measure
taVNS
n=20 Participants
Participants receive five consecutive daily 30-minute sessions of transcutaneous auricular vagus nerve stimulation using the Nurosym device. The electrode is positioned on the left tragus.
Sham
n=20 Participants
Participants receive five consecutive daily 30-minute sessions of transcutaneous auricular vagus nerve stimulation using the Nurosym device. The electrode is positioned on the left earlobe
Feasibility (Retention Rate)
20 Participants
20 Participants

PRIMARY outcome

Timeframe: From the first to the fifth stimulation session (Days 1-5), with adverse events assessed immediately before and after each intervention session.

Tolerability was assessed by monitoring adverse events before and after each session through visual inspection of the stimulation site and open-ended participant self-report questioning. The number of participants who discontinued participation due to any adverse event was recorded.

Outcome measures

Outcome measures
Measure
taVNS
n=20 Participants
Participants receive five consecutive daily 30-minute sessions of transcutaneous auricular vagus nerve stimulation using the Nurosym device. The electrode is positioned on the left tragus.
Sham
n=20 Participants
Participants receive five consecutive daily 30-minute sessions of transcutaneous auricular vagus nerve stimulation using the Nurosym device. The electrode is positioned on the left earlobe
Tolerability (Adverse Events / Dropout Due to AEs)
0 Participants
0 Participants

Adverse Events

taVNS

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

Sham

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Paulo Chaló

Egas Moniz School of Health and Science

Phone: (+351) 212 946 700

Results disclosure agreements

  • Principal investigator is a sponsor employee
  • Publication restrictions are in place