Clinical trial NCT03489694: Repeatability and Reproducibility of Skin Test Endpoint Titration
Official title: Within-tester Repeatability and Between-tester Reproducibility of Skin Test Endpoint Titration
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Allergic Reaction
Keywords: skin test endpoint
Lead sponsor: University of Saskatchewan
Sponsor class: OTHER
First posted: 2018-04-05
Enrollment: 17
Sex: ALL
Minimum age (years): 18
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Participants will be recruited from the local community.

Brief summary: This study will examine the within-tester repeatability and between-tester reproducibility of skin test endpoint titrations performed in those with allergic sensitivities.

Detailed description: Participants will be recruited from the local community. Participants with a previous history of skin prick testing in our lab will not be required to undergo preliminary skin prick testing, as the allergen to be used for skin prick titrations is known. New participants will undergo skin prick testing. The procedures for skin prick testing and skin test endpoint (STE) titration will be guided by the AllerGen CIC Allergen Skin Titration by Epicutaneous Method (Prick) Standard Operating Procedure. Different allergen extracts for the skin prick test or different doubling doses of an allergen in duplicate for the STE will be applied to the forearm, pricked with a lancet, and assessed ten minutes later by measuring the wheal sizes produced. The study will require three visits to the lab (i.e. three testers), each separated by one week and lasting roughly 30 minutes. Each visit will entail the duplicate STE procedure performed by a different tester. If a participant is new to the lab, they will undergo skin prick testing during their first lab visit prior to undergoing the skin prick titration and so, their first study visit may last up to one hour.

Eligibility criteria: Inclusion Criteria:

* must have allergic sensitivities confirmed by a skin prick test (or historically) to at least one of the study allergens

Exclusion Criteria:

* skin condition on the forearms
* if there is a situation where interpretation of skin reactions would be difficult (e.g. sleeve tattoos, scarring)
* regular use of anti-histamines (assessed on a case-by-case basis)

Primary outcomes:
measure: Within-tester repeatability
timeFrame: 10 minutes post skin pricking
measure: Between-tester reproducibility
timeFrame: approximately 3 weeks (one week washout between tests)
Secondary outcomes:
Other outcomes:
Locations:
city: Saskatoon
country: Canada
facility: Asthma Research Lab - University of Saskatchewan
state: Saskatchewan
Study officials:
affiliation: University of Saskatchewan
name: Dr. Don Cockcroft, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Blais CM, Davis BE, Cockcroft DW. Within-tester repeatability and between-tester reproducibility of skin test endpoint titration: A quality assurance study. Ann Allergy Asthma Immunol. 2019 Feb;122(2):220-222. doi: 10.1016/j.anai.2018.10.009. Epub 2018 Oct 14. No abstract available.