Tracking the Medico-Legal Recognition of Occupational COVID-19 in Italy: A Nationwide Repeated-Snapshot and Sensitivity Analysis of Workers’ Compensation Claims, 2020–2023

In Italy, occupational SARS-CoV-2 infection entered the accident-at-work system through a distinctive medico-legal framework. We examined whether the positive-disposition proportion differed from contemporaneous non-COVID injury claims and changed as administrative series matured. We harmonized 3,129,447 records from the Italian National Institute for Insurance against Accidents at Work (INAIL) and combined them with 32 national occupational COVID-19 reports. Repeated snapshots assessed completed 2020 and 2021 series; same-cut-off analyses compared COVID-19 with reconstructed non-COVID claims for 2020–2022. Published positive-disposition proportions rose from 87% to 89% for 2020 claims and from 66.5% to 74% for 2021 claims. At 30 April 2023, proportions were 89%, 74%, and 70% for COVID-19 versus 62.85%, 63.42%, and 59.15% for non-COVID claims, yielding differences of 26.15, 10.58, and 10.85 percentage points. All tested rounding and insurance-management scenarios retained positive differences. Denominator sensitivity was greatest in 2021, where the reference difference reached zero after the exclusion of 94.8% of communication/franchise records; the reference tipping point was not reached within 0–100% exclusion in 2020 or 2022. These are administrative outcomes at specified cut-offs; the more recent event years had less time to mature. Positive-disposition proportions should, therefore, be interpreted jointly with claim composition, denominator specification, and administrative follow-up when comparing compensation statistics and planning surveillance for future occupational epidemics.