Randomization and intervention
CORONAVIRUS DISEASE 2019, INFLUENZA
We used a stepped‐wedge cluster‐randomized trial, where randomization occurred at the cluster (shelter) level. The design involved monthly random and sequential crossover of clusters from control periods to intervention periods with influenza testing at kiosks until all clusters implemented the intervention. Nine shelters were randomized to the four sequences, with rerandomization at the start of each year (Figure Stepped‐wedge cluster‐randomized trial design and shelter randomization assignments, Years 1 and 2. COVID‐19, coronavirus disease 2019; RCT, randomized controlled trial