Get a cohort definition by ID

Retrieves the full definition of a specific cohort from each connected server, including the inclusion criteria and any metadata stored with the cohort definition.

Usage

ds.omop.cohort.definition(id, symbol = "omop", conns = NULL)

Arguments

id

Integer; the cohort definition ID to retrieve. An id that is unknown or below the disclosure threshold returns the same not-available result (see Disclosure control), so a usable definition requires a cohort that appears in ds.omop.cohort.list.

symbol

Character; the session symbol used when the OMOP connection was initialised (default: "omop").

conns

DSI connection object(s). If NULL (the default), the connections stored in the active session are used.

Value

Named list (one entry per server) with definition details for an available (at- or above-threshold) cohort. For an unavailable id – absent OR sub-threshold – the server returns its uniform not-available response (identical for both cases), surfaced unchanged by the client.

Disclosure control

An id that is not available – whether because no such cohort exists OR because the cohort exists but is below the server's per-subset threshold (nfilter_subset) – yields the SAME "not available" result. The two cases are deliberately indistinguishable: a sub-threshold cohort is treated as nonexistent, and the server's response for it is identical to that for a genuinely unknown id (it never says "too small" or otherwise hints that a small cohort exists, which would itself confirm its existence). The client surfaces the server's response as-is and adds no distinction of its own, so a caller cannot tell small-but-present from absent from either side. Only definitions of cohorts at or above the threshold (the ones that appear in ds.omop.cohort.list) are readable.

See also

ds.omop.cohort.list

Examples

if (FALSE) { # \dontrun{
defn <- ds.omop.cohort.definition(id = 1)
defn[["server_a"]]
} # }