Paid sick leave reduces workplace transmission of infectious disease

Quality and quantity of direct evidence for or against the claim — RCTs, systematic reviews, natural experiments, large cohort studies.

Pichler & Ziebarth's (2017) quasi-experimental analysis of staggered sick-pay mandates found flu rates fall when workers gain paid sick leave access, providing strong direct support.

Whether the proposed mechanism is valid and established — does the how make sense, or are there fundamental flaws in the causal logic?

The contagious-presenteeism mechanism (workers without paid leave attend work while infectious) is well-validated theoretically and empirically across the sick-pay literature.

Degree of agreement among domain experts and relevant scientific or policy bodies — depth and quality of consensus, not just majority opinion.

Labor and public health economists broadly accept the transmission-reduction finding, replicated during COVID-19 via the FFCRA natural experiment.

Whether findings hold across independent studies, populations, and contexts — resistance to p-hacking and publication bias.

The finding replicates across Pichler & Ziebarth's original influenza analysis and their subsequent COVID-19 emergency sick leave study (Pichler, Wen & Ziebarth 2020).