Freeze the surveillance series and the held-out hospital split

Freeze the surveillance series and the held-out hospital split

Define eligibility for de-identified E. coli bloodstream isolate counts by quarter, the resistance definition, the minimum isolates per hospital-quarter, and a hospital-disjoint split. Record the data use terms before extraction. Deliverable: A series manifest with hospital and quarter counts, a data use record, and a statement that freezing the series produces no forecast.