Figure 1
From: Post-hospital syndrome in adults with asthma: a case-crossover study
Schematic illustration of the cohort construction and analysis type.
The arrow from left to right represents the timeline of an individual within the data. The vertical arrow shows an outcome date (admission to hospital due to asthma). The immediate 30-day prior to this date constitutes the case time window. For each subject, up to two control time windows of the same length were also selected, each 364 days before and after the start of the case time window. The presence of discharge from a hospitalization in the case and control-time windows defines the exposure.