Do State and Trait Affect Measures Retain Their Measurement Properties during a Disaster? An Investigation of Measurement Invariance during the COVID-19 Pandemic.

Psychologists have begun to study the impact of the COVID-19 pandemic on emotionality, though such investigations assume that the measurement properties of affect scales have not changed as a function of the pandemic. To our knowledge, no prior study has tested measurement invariance (MI) of an affect scale during a disaster, and very few studies have explored MI of scales administered through ecological momentary assessment (EMA). The current study tested invariance of trait and state affect measures across homogenous groups of 18-year-olds assessed prior to and during the first acute phase of the COVID-19 pandemic in Long Island, New York. Trait affect was measured with a single administration of the Schedule for Nonadaptive and Adaptive Personality-Youth Version. State affect was assessed with items developed for the EMA portion of this study, which were administered 5 times daily for 14 consecutive days using a smartphone application. A baseline correlated 2-factor (positive and negative affect) model was fit for both measures. Invariances tests established up to strict MI across pre-/COVID-19 groups for both affect measures. These findings suggest that valid comparisons of observed score means and variances can be made between groups assessed before and during the COVID-19 pandemic.