Missing visit start date

[solmazeradat]

Missing visit start date

CDM or THEMIS convention?

CDM

Table or Field level?

Field

Is this a general convention?

No

Summary of issues

• EHR records that have missing visit_start_date

Summary of answer

• If possible, to workout the date from records provided. Otherwise, drop the visit entirely.

• The use of default dates such as 1800-01-01 or 1900-01-01 will cause analyses issues.

Related links

• https://forums.ohdsi.org/t/missing-visit-start-date/16470

Other comments/notes

• Suggestion would be to add a comment to the CDM documentation. "If field is missing then drop record