Sensitivity of Self-collected Skin Sampling for Scabies: a Pilot Study
NCT Number: NCT06546579
Acronym: SCRAPE
Status: RECRUITING
Study Type: INTERVENTIONAL
Phases: EARLY_PHASE1
Conditions: Scabies
Interventions: DIAGNOSTIC_TEST: Skin sampling
Sponsor: Radboud University Medical Center
Sex: ALL
Age: ADULT, OLDER_ADULT
Enrollment: 144
Study Design: Allocation: NA|Intervention Model: SINGLE_GROUP|Masking: NONE|Primary Purpose: DIAGNOSTIC
Start Date: 2024-08-21
Completion Date: 2025-06
Locations: Radboudumc, Nijmegen, Gelderland, 6525GA, Netherlands

Summary:
In this cross-sectional diagnostic study, healthy adults aged 18 and older with suspected, clinical, or confirmed scabies will be recruited. The objective is to determine if the sensitivity of self-collected skin samples for scabies diagnosis is non-inferior to professional sampling, and compare the sensitivity and specificity of the polymerase chain reaction assay (PCR) versus microscopy.

Primary Outcome Measures: The sensitivity of self-collected skin samples for diagnosing scabies, The proportion of self-collected samples collected at the enrolment visit that are tested positive, divided by the total number of participants adjudged retrospectively to have had scabies at their enrolment visit, based on a composite clinical diagnosis., through study completion, an average of one year|The sensitivity of professionally-collected skin samples for diagnosing scabies, The proportion of professionally-collected samples collected at the enrolment visit that are tested positive, divided by the total number of participants adjudged retrospectively to have had scabies at their enrolment visit, based on a composite clinical diagnosis., through study completion, an average of one year
Secondary Outcome Measures: The sensitivity of skin scrapings for diagnosing scabies, The proportion of skin scrapings at their enrolment visit (whether professionally or self-collected) that are tested positive by PCR, divided by the total number of participants adjudged retrospectively to have had scabies at baseline, based on a composite clinical diagnosis., through study completion, an average of one year|The sensitivity of skin swabs for diagnosing scabies, The proportion of skin swabs at their enrolment visit (whether professionally or self-collected) that are tested positive by PCR, divided by the total number of participants adjudged retrospectively to have had scabies at baseline, based on a composite clinical diagnosis., through study completion, an average of one year|The sensitivity and specificity of PCR on skin scraping for diagnosing active scabies infection, The proportion of participants adjudged to have had scabies at their enrolment visit (based on a retrospective composite clinical diagnosis), whose skin scraping at their enrolment visit (whether professionally or self-collected) are tested positive for scabies by PCR, and the proportion of participants adjudged retrospectively to have not had scabies at their enrolment visit whose skin scrapings are tested negative for scabies by PCR., through study completion|The sensitivity and specificity of microscopy on skin scraping for diagnosing active scabies infection, The proportion of participants adjudged to have had scabies at their enrolment visit (based on a retrospective composite clinical diagnosis), whose skin scraping at their enrolment visit (whether professionally or self-collected) are tested positive for scabies by microscopy, and the proportion of participants adjudged retrospectively to have not had scabies at their enrolment visit whose skin scrapings are tested negative\* for scabies by microscopy., through study completion, an average of one year
Other Outcome Measures: Proportion of participants whose self-sampling location is judged appropriate, Assessed by a professional at T=0 \[adequate/non-adequate\], through study completion, an average of one year|Motivation for self-collection of skin samples for scabies diagnostics, Motivation is assessed by items on the questionnaire related to the motivation for self-collection of skin samples for scabies diagnostics, along with the associated facilitators and barriers., through study completion, an average of one year|Demographic, clinical and epidemiological factors which influence the sensitivity of self-collected skin samples for scabies diagnosis., Age, gender, highest level of education, signs/symptoms, living situation, skin color. source of transmission and transmission mode., through study completion, an average of one year