Open- and closed-label suggestions and itch

Recruiting

Conditions: Itch, expectations
Jeuk, verwachtingen

Registration Number: NL-OMON27413

Lead Sponsor: eiden University

Brief Summary: n/a

Detailed Description: Not available

Recruitment & Eligibility

Status: Recruiting

Sex: Not specified

Target Recruitment: 112

Inclusion Criteria

Between 18 and 35 years old; good understanding of both written and spoken Dutch

Exclusion Criteria

Refusal to give written informed consent; severe somatic or psychological morbidity (e.g., heart and lung diseases or DSM-V psychiatric disorders) that would adversely affect participant’s safety or that might interfere with the study protocol; current chronic itch or pain complaints; current use of analgesics, anti-inflammatory drugs, antihistamines, or antibiotics; recent vaccinations; pregnancy; colour blindness.

Study & Design

Study Type: Interventional

Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
The primary study outcome is the difference in self-reported itch rating during a short-term validated histamine test (histamine iontophoresis) between the combined open- and closed-label negative verbal suggestion group and the combined open- and closed-label positive verbal suggestion group.

Secondary Outcome Measures

Name	Time	Method
To investigate whether open-label verbal suggestions and closed-label verbal suggestions alone are able to induce outcome expectations and influence self-reported itch, separate analyses will be conducted for each type of verbal suggestions. The effects of suggestions (both combined and for open-label and closed-label separately) on outcome expectations will be assessed.<br><br /><br /><br>In addition, the effects of suggestions (both combined and for open- and closed-label conditions separately) on secondary outcomes, for example skin condition, and wellbeing, will be explored. Furthermore, the possible influence of psychological parameters on the expectation induction and study outcomes will be explored.