Columbia Open Health Data (COHD)
The Columbia Open Health Data (COHD) API provides access to observed clinical frequencies and co-occurrence frequencies from electronic health records at Columbia University Medical Center. The database contains counts and frequencies of conditions, procedures, drug exposures, and patient demographics from the OHDSI common data model, along with statistical associations between clinical concepts. To protect patient privacy, all concepts where count ≤10 were excluded and counts were randomized using Poisson distribution. COHD offers multiple datasets including 5-year (2013-2017) and lifetime data, both in hierarchical and non-hierarchical forms, plus beta temporal co-occurrence data.
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