Developing an Objective Measure of Experienced Pain

University of Zurich (UZH)

Status: Completed

Conditions: Pain, Acute

Treatments: Behavioral: Developing an objective measure of experienced pain

Study type: Interventional

Funder types: Other

Identifiers

NCT05415423

2022-00236

Details and patient eligibility

About

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.

Full description

The aim of this study is to establish and validate the proposed method of measuring pain using different pain stimuli. The investigators correlate these measurements with physiological data such as skin-conductance, heart-rate variability, pupil dilation, and with established measures of pain such as Numeric rating scale (NRS), Visual analog scale (VAS), general Labeled Magnitude Scale (gLMS). In addition, the investigators study the test-retest reliability of our measure of pain and its ability to capture a reduction in experienced pain due to a topical analgesic product compared to a placebo treatment.

Enrollment: 330 patients

Sex: All

Ages: 18 to 60 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• 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).

Exclusion criteria

• 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).

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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330 participants in 7 patient groups, including a placebo group

Study 1 Low-Intensity Group

Active Comparator group

Description:

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

Treatment:

Behavioral: Developing an objective measure of experienced pain

Study 1 High-Intensity Group

Experimental group

Description:

Group which receives more intense electrical stimuli than the other.

Treatment:

Behavioral: Developing an objective measure of experienced pain

Study 2 Low-Intensity Group

Active Comparator group

Description:

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

Treatment:

Behavioral: Developing an objective measure of experienced pain

Study 2 High-Intensity Group

Experimental group

Description:

Group which receives more intense heat stimuli than the other.

Treatment:

Behavioral: Developing an objective measure of experienced pain

Study 3 Placebo group

Placebo Comparator group

Description:

A group that receives a placebo cream.

Treatment:

Behavioral: Developing an objective measure of experienced pain

Study 3 Painkiller group

Experimental group

Description:

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

Treatment:

Behavioral: Developing an objective measure of experienced pain

Study 4 test-retest reliability group

No Intervention group

Description:

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