Cross-Sectional Measurement Properties of the Physical Distancing Scale – COVID-19 (PDS-C19) Self- and Observer-Reported Measure of Physical Distancing Behaviors to Avoid COVID-19 in Adults, Children, and Caregivers
Author(s)
Powell PA1, Marcus J2, Venkatesan S3, Williams P4, Arnetorp S5, Herring TA6, Lloyd A7, Severens JL8, Varni J9, Yokota RTC10, Maia T11, Taylor S3, Krol M12, Ware Jr. JE13
1University of Sheffield, Sheffield, South Yorkshire, UK, 2IQVIA, US, Washington, DC, USA, 3AstraZeneca, Cambridge, Cambridgeshire, UK, 4IQVIA, Courbevoie, Île-de-France, France, 5AstraZeneca, Gothenberg, Västergötland, Sweden, 6AstraZeneca, Wilmington, DE, USA, 7Acaster Lloyd Consulting Ltd, London, UK, 8Severens HTA Consultancy, Venray, Limburg, Netherlands, 9Texas A&M University, College Station, TX, USA, 10P95, Leuven, Flemish Brabant, Belgium, 11IQVIA, Porto Salvo, Oeiras, Portugal, 12IQVIA, Amsterdam, ZH, Netherlands, 13John Ware Research Group, Worcester, MA, USA
OBJECTIVES: Individuals, especially high-risk populations, may alter their behaviors to avoid COVID-19. The PDS-C19 is a novel instrument developed to assess physical distancing behaviors to avoid COVID-19. The initial PDS-C19 consisted of nine frequency items (4-week recall period, response levels: never, rarely, sometimes, often, always), for self-report (ages 13+ years) and caregiver proxy-report (ages ≤12 years). This study aimed to assess the psychometric properties of the initial PDS-C19.
METHODS: The EAGLE Study was a cross-sectional, online survey of immunocompromised and non-immunocompromised adults (N enrolled=2,679) and child-caregiver dyads (N enrolled=1,502) conducted in US and UK (December 2022-June 2023). Psychometric properties (structural validity, internal consistency, construct validity) were assessed on a randomly sampled subpopulation from the EAGLE study in the following ratios: 2:1 immunocompromised vs non-immunocompromised, 3:3:1 adult vs child vs caregiver, 1:1 gender, and 1:1 country.
RESULTS: The psychometric sample consisted of 1,059 participants: adults (43.3%), caregivers (14.0%), and children: 0.5-4 years (6.9%), 5-12 years (21.4%), 13-17 years (14.4%); 42.9% had 3+ COVID-19 vaccine doses.
Factor analyses demonstrated a single factor. Two items were removed per high residual correlations and differential item functioning by age. Remaining items were highly intercorrelated (range: 0.71-0.87). PDS-C19 item floor effects ranged 27.2%-48.8% and ceiling effects ranged 4.2%-12.6%. Confirmatory factor analysis had good model fit (SRMR: 0.012) and IRT analyses confirmed ordered thresholds. Latent PDS-C19 scores were derived using a centering sample of those who engaged in distancing (N=796).The PDS-C19 score exhibited high internal consistency (McDonald omega: 0.97, Cronbach’s alpha: 0.95) correlated as hypothesized with related scales (e.g., SF-12v2, QDIS-7, PedsQL scales, EQ-5D), and differentiated among groups defined by reasons for leaving home, COVID-19 worry, and daily close contact (each p<0.001).CONCLUSIONS: The PDS-C19 generated a reliable single score with evidence of construct validity, supporting its use for measuring the extent of physical distancing to avoid COVID-19 across age groups.
Conference/Value in Health Info
Value in Health, Volume 26, Issue 11, S2 (December 2023)
Code
PCR118
Topic
Patient-Centered Research
Topic Subcategory
Instrument Development, Validation, & Translation, Patient Behavior and Incentives, Patient-reported Outcomes & Quality of Life Outcomes
Disease
Infectious Disease (non-vaccine), No Additional Disease & Conditions/Specialized Treatment Areas