Group A. People suffering difficulties requiring antidepressant/anxyolytic treatment and exposed to fluvoxamine – at least one (repeatable) prescription for fluvoxamine issued in the period between 90 days prior to- and 7 days after the index COVID-19 diagnosis (see Study outline). This also means that they had International Classification of Disease (ICD-10) code entries pertaining to ICD-10 F codes in which fluvoxamine might have been the main or one of the treatments at any time between January 1 2019 and the date of the index COVID-19 diagnosis, and might have been prescribed also other psychiatric treatments during this period.
Group B. People suffering difficulties requiring antidepressant/anxyolytic treatment not exposed to fluvoxamine – (i) at least one ICD-10 F or G30/G31.1 code entry at any time between January 1 2019 and the date of the index COVID-19 diagnosis, and (ii) no prescription for fluvoxamine issued in the period between 6 months prior to- and 21 days after the index COVID-19 diagnosis. This also means that they might have been prescribed any other psychiatric treatment at any time between January 1 2019 and the date of the index COVID-19 diagnosis.
Group C. People free of psychiatric difficulties and not exposed to fluvoxamine or to any other pharmacological psychiatric treatment – (i) no ICD-10 F code entries at any time between January 1 2019 and 21 days after the index COVID-19 diagnosis, and (ii) no prescriptions for fluvoxamine or any of the other drugs falling into the Anatomical Therapeutic Chemical codes N05, N06 or N07B in the period between 6 months prior to- and 21 days after the index COVID-19 diagnosis.
Group A vs. Group B: the two subsets differ regarding the (presumed) exposure to fluvoxamine in the early phases of COVID-19 disases, while it is reasonable to assume that the burden of psychiatric difficulties (and related treatments) is generally similar. This contrast intends to quatify the “effect” of exposure to (i.e., of the fact of being issued a prescription for) fluvoxamine in the early phase of COVID-19.
Group A vs. Group C: the two subsets differ regarding the burden of psychiatric conditions and the fact of exposure to fluvoxamine. This contrast intends to quantify the (joint) “effect” of psychiatric conditions (including therapies used to treat them) and of exposure to fluvoxamine.
Group B vs. Group C: the two subsets differ regarding the burden of psychiatric conditions including their respective treatments (except for fluvoxamine). This contrast intends to quantify the (joint) “effect” of psychiatric conditions and their respective tretments, which, however, do not include fluvoxamine.