The Effects of Open-label Placebos on Acute Stress

The goal of this study is to find out whether an open-label placebo nasal spray can reduce stress among individuals engaging in a high-stress canyon swing. The main questions the study aims to answer are: 1) Does an open-label placebo increase likelihood of participants completing another jump? 2) Does the placebo affect how long it takes participants to jump, reduce the reported stress levels before the jump 3) Does the placebo change how enjoyable participants find the jump?

Researchers will compare participants who receive an open-label placebo nasal spray (a spray that contains no active medication and is clearly described as a placebo) with participants who receive no treatment (control). The aim is to see whether the placebo nasal spray can increase likelihood of participants completing another jump, reduce reported stress and improve participants overall enjoyment of the jump.

Participants will:

• Complete a short questionnaire before they jump
• Either self administer a placebo nasal spray (one spray in each nostril) right before stepping through the gate to jump, or receive no treatment (control).
• Complete a short questionnaire after completing the jump
• Whether they complete another jump will be noted

Study Overview

• Status: Not yet recruiting
• Conditions: Stress; Acute Stress
• Intervention / Treatment: Other: Open Label Placebo

Detailed Description

This randomised controlled trial evaluates whether an open label placebo can increase likelihood of participants completing another jump and reduce stress among individuals engaging in a high-stress canyon swing. The intervention is based on prior research on placebo effects - which suggest that expectations and prior learning can produce meaningful physiological and psychological responses to a treatment - even when individuals are aware they are receiving a placebo, known as an open-label placebo. Open-label placebos challenge traditional assumptions by offering an ethically acceptable way to harness the mechanisms of placebos without deception. Prior research shows that open-label placebos can improve a range of self-reported outcomes including reducing stress, pain, and anxiety.

The study examines the effects of an open-label placebo on stress in a real world setting. The primary objective is to assess whether an open-label placebo nasal spray can increase likelihood of participants completing another jump. Secondary objectives include examining whether the placebo influences reported stress time taken to jump, and ratings of the jump in terms of enjoyment.

Participants who have signed up to complete the Shotover Canyon Swing Queenstown and meet the eligibility criteria are randomly assigned in a 1:1 ratio to one of two study arms; either an open-label placebo group or no-treatment control group. Randomisation is conducted independently using a computer-generated allocation sequence. Participants in the placebo group will self-administer the nasal spray once in each nostril immediately prior to stepping through the gate to jump. The nasal spray is made of a saline solution and is explicitly described as a placebo with no active ingredients. Participants in the control group receive no intervention and continue as normal. Statistical analyses will include independent samples t-tests to compare mean differences in primary and secondary outcomes between groups. Missing data will be addressed using multiple imputation techniques. All eligibility criteria, outcome measures and intervention details are specified in the relevant sections of the clinical trial registration record. This trial contributes to a growing body of research examining the effects of open-label placebos and explores whether these mechanisms extends the research into naturalistic, non-clinical settings.

• Study Type: Interventional
• Enrollment (Estimated): 260
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Keith J Petrie, PhD; Phone Number: 6493737599; Email: kj.petrie@auckland.ac.nz

Study Locations

• New Zealand
  • Otago
    • Queenstown, Otago, New Zealand, 9300
      • Canyon Swing

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Signed-up to complete the canyon swing
• Aged 18 years and over
• Able to speak and understand English
• Comfortable being randomised to either the open-label placebo or no-treatment control condition

Exclusion Criteria:

• Under 18 years of age
• Unable to speak or understand English
• Unable to provide informed consent

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Open label placebo; Participants in this arm are assigned to receive a placebo nasal spray. This arm allows testing of the effects on an open-label placebo compared to a control condition. Participants in this arm will self-administer the nasal spray once in each nostril before entering through the gate to jump.	Other: Open Label Placebo; Participants allocated to the placebo arm will self-administer the nasal spray before entering through the gate to jump. The nasal spray contains no active ingredients. It is made of a saline solution and is described to participants as a placebo. Participants are informed that placebos can produce powerful effects and have been shown to reduce stress and anxiety through expectations and prior learning - processes where the body learns to respond automatically to cues that are associated with a relief in symptoms.
No Intervention: Control; Participants in this arm receive no treatment and will continue as normal. This group serves as a no intervention comparator to assess the effects of the open label placebo.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Repeat jump	Whether participants choose to complete a repeat jump after their initial jump.	During the same study session, immediately following completion of the participant's initial jump.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Self reported stress	Participants self-reported stress related to the jump measured at baseline (prior to the jump) and post-jump. Measured at baseline with the question: How anxious do you feel about the jump today? 0 (Not at all) - 10 (Extremely) Measured post-jump with the question: How anxious were you right before you jumped? 0 (Not at all) - 10 (Extremely)	Answered at baseline on the pre-jump questionnaire and immediately after completion of the jump on the post-jump questionnaire, during the same study session.
Time to jump	The amount of time taken for participants to jump after being clipped on to the main attachment point (rigging plate).	During the study session. Time is recorded in seconds. The recording starts when the participant is clipped onto the main attachment point rigging plate and stops recording when they leave the jump platform and drop into the canyon.
Enjoyment of the jump	Participants self-reported enjoyment of the jump. Measured with the question: Firstly, how much did you enjoy your jump? 0 (Not at all) - 10 (Extremely)	Answered immediately after completion of the jump on the post jump questionnaire, during the same study session.
Willingness to jump again	Participants self-reported willingness to jump again. Measured with the question: If given the opportunity, would you do another jump today? Answer: YES or NO	Answered immediately after completion of the jump on the post jump questionnaire, during the same study session.

Collaborators and Investigators

• Sponsor: University of Auckland, New Zealand

Study record dates

Study Major Dates

• Study Start (Estimated): April 1, 2026
• Primary Completion (Estimated): November 1, 2026
• Study Completion (Estimated): November 1, 2026

Study Registration Dates

• First Submitted: February 24, 2026
• First Submitted That Met QC Criteria: April 9, 2026
• First Posted (Actual): April 13, 2026

Study Record Updates

• Last Update Posted (Actual): April 13, 2026
• Last Update Submitted That Met QC Criteria: April 9, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: Acute stress; Open label placebo; Canyon Swing
• Other Study ID Numbers: UAHPEC30520

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No