CAN A COMPOSITE MEASURE COMPREHENSIVELY CAPTURE THE BURDEN OF NOCTURNAL SCRATCH?
Author(s)
Aleksandra Sjöström-Bujacz, PhD1, Gerasimos Dumi, MSc2, Gaizka Perez, MSc3, Pavol Král, PhD4, Salma Ajraoui, PhD5, Christine Guo, PhD6, Sylvain Zorman, PhD6, Konstantina Skaltsa, BSc, PhD7.
1Patient Centered Solutions, IQVIA, Stockholm, Sweden, 2IQVIA, Athens, Greece, 3IQVIA, Madrid, Spain, 4IQVIA, Banská Bystrica, Slovakia, 5IQVIA, London, United Kingdom, 6Ametris, Pensacola, FL, USA, 7IQVIA, Barcelona, Spain.
1Patient Centered Solutions, IQVIA, Stockholm, Sweden, 2IQVIA, Athens, Greece, 3IQVIA, Madrid, Spain, 4IQVIA, Banská Bystrica, Slovakia, 5IQVIA, London, United Kingdom, 6Ametris, Pensacola, FL, USA, 7IQVIA, Barcelona, Spain.
OBJECTIVES: Inflammatory skin diseases involve symptoms of itch and scratching, but nocturnal scratching is harder to assess subjectively than itch severity, which has driven the development of digital algorithms to quantify nocturnal scratching. This study evaluated whether a composite measure combining patient-reported itch severity and digitally measured nocturnal scratching is clinically valid and performs at least as well as its individual components.
METHODS: In the DECODE-Nocturnal Scratch study, 42 participants were asked to complete a daily morning PRO item assessing itch severity for 14 consecutive days. Nocturnal scratch behavior was simultaneously measured using the ActiGraph LEAP device and operationalized as time spent scratching during the sleep opportunity. Analyses were conducted separately for each individual measure and for two composite scores: an unweighted average and a weighted composite accounting for differences in the standard deviations of the individual measures. Construct validity was evaluated by assessing differentiation between known groups defined by the clinician-reported disease severity scores (Eczema Area and Severity Index [EASI], SCORing Atopic Dermatitis [SCORAD]), and the patient-reported quality-of-life scores (Patient-Oriented Eczema Measure [POEM], Dermatology Life Quality Index [DLQI]). The level of association with the same reference measures was also evaluated for both individual and composite scores.
RESULTS: Both single components and composite measures showed mostly small separation between severity groups. They also associated with reference measures in the expected direction and with weak to moderate strength. The evidence of construct validity was equivalent for both composite scores. In the context of this study, the composite scores performed similarly to individual measures when evaluated independently.
CONCLUSIONS: Combining PROs with objective digital parameters may support a more comprehensive understanding of the symptom burden in inflammatory skin diseases. Further longitudinal studies are needed to confirm that the proposed composite score is clinically valid, as well as to assess its ability to detect change over time.
METHODS: In the DECODE-Nocturnal Scratch study, 42 participants were asked to complete a daily morning PRO item assessing itch severity for 14 consecutive days. Nocturnal scratch behavior was simultaneously measured using the ActiGraph LEAP device and operationalized as time spent scratching during the sleep opportunity. Analyses were conducted separately for each individual measure and for two composite scores: an unweighted average and a weighted composite accounting for differences in the standard deviations of the individual measures. Construct validity was evaluated by assessing differentiation between known groups defined by the clinician-reported disease severity scores (Eczema Area and Severity Index [EASI], SCORing Atopic Dermatitis [SCORAD]), and the patient-reported quality-of-life scores (Patient-Oriented Eczema Measure [POEM], Dermatology Life Quality Index [DLQI]). The level of association with the same reference measures was also evaluated for both individual and composite scores.
RESULTS: Both single components and composite measures showed mostly small separation between severity groups. They also associated with reference measures in the expected direction and with weak to moderate strength. The evidence of construct validity was equivalent for both composite scores. In the context of this study, the composite scores performed similarly to individual measures when evaluated independently.
CONCLUSIONS: Combining PROs with objective digital parameters may support a more comprehensive understanding of the symptom burden in inflammatory skin diseases. Further longitudinal studies are needed to confirm that the proposed composite score is clinically valid, as well as to assess its ability to detect change over time.
Conference/Value in Health Info
2026-11, ISPOR Europe 2026, Vienna, Austria
Value in Health, Volume 29, Issue 12S
Code
PCR37
Topic
Clinical Outcomes, Methodological & Statistical Research, Patient-Centered Research
Topic Subcategory
Instrument Development, Validation, & Translation
Disease
Sensory System Disorders (Ear, Eye, Dental, Skin)