Condition_start_date when only the year is available

[ivona]

Hello!

I am currently transforming clinical study data into the OMOP cdm (version 5.3). In our study, we ask for several current conditions, but have only collected information on the year of diagnosis (day+month of diagnosis is missing). Would it be fine in terms of the logic the condition occurence table to assign default values to day+month (e.g. 01.01) or does the absence of the values mean that we should move these findings to the observation table?

I am very thankful for any advice on this topic.

Best
Ivona

[Eduard_Korchmar]

I think it would be preferable to keep these events in condition_occurrence, as long as they fall outside of any existing observation_period entries; this way, patients that only have a historical record with approximated date will not affect cohort creation if the said condition will be used as a cohort index definition.