effectiveInstant property
effectiveInstant The time or time-period the observed value is asserted as being true. For biological subjects - e.g. human patients - this is usually called the "physiologically relevant time". This is usually either the time of the procedure or of specimen collection, but very often the source of the date/time is not known, only the date/time itself.
Implementation
FhirInstant? get effectiveInstant => throw _privateConstructorUsedError;