Developing an Objective Measure of Experienced Pain

NCT05415423 | Completed

• 1 other identifier: 2022-00236
• Study Type: interventional
• Target: 330
• Locations: 1 country
• Sites: 1

Brief Summary

Pain is a public health challenge around the world. However, there is no single standardized measure of pain, to the point that the estimated prevalence of chronic pain in adults ranges between 2% and 64% depending on the methods and definitions used. Existing measures of pain are known to present several problems and results can be hardly compared between people. The investigators propose and empirically validate a new, simple method to measure experienced pain in clinical trials. The method provides an objective, cardinal measurement of experienced pain which is comparable between people and the investigators test whether it is better able to measure experienced pain than existing procedures. The investigators test the new method in healthy participants using standard protocols (electrical and heat stimuli). The investigators also aim to validate the measure using a causal manipulation which relies on the administration of a topical analgesic product compared to a placebo.

Conditions

Pain, Acute

Keywords

Measurement of Pain; Pain

Outcome Measures

Primary Outcomes (5)

• Choices between monetary amounts and painful stimuli

  Participants' choices between monetary amounts and painful stimuli

  baseline

• self-reported pain ratings according to Numerical Rating Scale (NRS)

  self-reported pain ratings according to Numerical Rating Scale

  baseline

• self-reported pain ratings according to Visual Analogue Scale (VAS)

  self-reported pain ratings according to Visual Analogue Scale

  baseline

• self-reported pain ratings according to general Labeled Magnitude Scale (gLMS)

  self-reported pain ratings according to general Labeled Magnitude Scale

  baseline

• response times

  Response times relative to participants' choices between monetary amounts and painful stimuli

  baseline

Secondary Outcomes (3)

• heart rate variability

  baseline

• skin conductance

  baseline

• pupil dilation

  baseline

Study Arms (7)

Study 1 Low-Intensity Group

ACTIVE COMPARATOR

Control group which receives less intense electrical stimuli than the other.

Behavioral: Developing an objective measure of experienced pain

Study 1 High-Intensity Group

EXPERIMENTAL

Group which receives more intense electrical stimuli than the other.

Behavioral: Developing an objective measure of experienced pain

Study 2 Low-Intensity Group

ACTIVE COMPARATOR

Control group which receives less intense heat stimuli than the other.

Behavioral: Developing an objective measure of experienced pain

Study 2 High-Intensity Group

EXPERIMENTAL

Group which receives more intense heat stimuli than the other.

Behavioral: Developing an objective measure of experienced pain

Study 3 Placebo group

PLACEBO COMPARATOR

A group that receives a placebo cream.

Behavioral: Developing an objective measure of experienced pain

Study 3 Painkiller group

EXPERIMENTAL

A group that receives a topical analgesic such as EMLA cream.

Behavioral: Developing an objective measure of experienced pain

Study 4 test-retest reliability group

NO INTERVENTION

Participants who participated in either Study 1 or 2 are recruited. They will experience both electrical and heat stimuli.

Interventions

Developing an objective measure of experienced pain BEHAVIORAL

At the beginning of each study, participants are randomly allocated into one of two groups. Within each group all participants are exposed to the same painful stimulus. One group experiences a painful stimulus of higher intensity compared to that of the other group. The painful stimuli are physically identical for every subject within the same group and within the standard of previous pain research. Participants are then asked to evaluate the painful stimulus they just received according to a self-reported scale (NRS, VAS, gLMS, NRS-MB). Participants are also asked to decide multiple times whether they prefer a larger amount of money and experience the same or more painful stimulus they received before or a smaller amount of money and no (or a less) painful stimulus. The smaller amount of money is progressively increased across choices until it matches the larger amount, similar to multiple price-list methods (MPL) which are standard in economics.

Study 1 High-Intensity Group; Study 1 Low-Intensity Group; Study 2 High-Intensity Group; Study 2 Low-Intensity Group; Study 3 Painkiller group; Study 3 Placebo group

Eligibility Criteria

• Age: 18 Years - 60 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• age 18-60 years.
• ability and willingness to participate in the study
• declaration of consent
• good English language skills (to ensure understanding of all instructions and the declaration of consent).

You may not qualify if:

• inability to give the declaration of consent (e.g. due to linguistic difficulties understanding the study information)
• any neurological disorders
• reduced general health / chronic diseases (e.g. autoimmune disease, severe cardiovascular diseases, insulin-dependent diabetes, severe depression); chronic pain disorders
• pregnancy
• in the week before the experimental session self-reported intake of drugs which could influence pain perception (e.g. cannabis and ADHD medications).

Sponsors & Collaborators

• University of Zurich: lead
• Balgrist University Hospital: collaborator

Study Sites (1)

SNS Laboratory

Zurich, CH, 8091, Switzerland

Location

MeSH Terms

Conditions

Acute Pain; Pain

Condition Hierarchy (Ancestors)

Neurologic Manifestations; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: May 30, 2022
• First Posted: June 13, 2022
• Study Start: June 6, 2022
• Primary Completion: September 26, 2022
• Study Completion: September 26, 2022
• Last Updated: October 12, 2022

Record last verified: 2022-10

Locations

CH (1)