Sensitivity to Change of COVID-19 Anxiety Measure in Canadian Dentists

Objectives: There is a need to further validate the COVID-19 Anxiety Syndrome Scale (C-19ASS) by evaluating its sensitivity to change over time.
To estimate the sensitivity to change of the C-19ASS in a sample of dentists practising in Canada over a period of 12 months.
Methods: Longitudinal data were used from a prospective cohort study investigating the incidence rate of COVID-19 among dentists in Canada during the period August 2020 to October 2021. A sample of 644 dentists from nine provinces was recruited. C-19ASS data were collected from study participants monthly from November 2020 to October 2021. Mixed effects ordinal logistic regression models were used to estimate the association between C-19ASS scores and follow-up time and COVID-19 case counts during the 14 days prior to completing the C-19ASS questionnaire in the province in which the participants were working. We hypothesized that anxiety would decrease with time, but would increase when local population COVID-19 infection rates increased.
Results: There was a negative association between follow-up time and the probability of participants reporting more severe anxiety. The odds of being in a more severe category of anxiety were reduced by 74% (Odds Ratio =0.74, 95% C.I. 0.72-0.76) with every increase of 30 days in study follow-up time. The odds of being in a more severe category of anxiety increased by 20% (O.R.= 1.20, 95% C.I.= 1.12-1.27) with every increase of 10,000 in the total count of COVID-19 cases in the province of primary practice of participating dentists during the 14 days prior to their completing the C-19ASS questionnaire, controlling for other variables. There was a positive association between local COVID-19 case burden and C-19ASS scores.
Conclusions: The C-19ASS responded over time and with external anxiety stimuli as hypothesized, so we conclude it is sensitive to change over time.