Updated information: Default dates are primarily present for CareMark (99CAR1). Date of birth (ME014) = ('1901-01-01','1911-11-11','1950-01-01') for 99CAR1 are default dates. It is recommended that 99CAR1 member records with dates of birth = '1901-01-01','1911-11-11','1950-01-01' or with Birth Year (if date of birth is not available) = 1901, 1911, 1950 be used with caution. Possible workaround - Find other enrollment records from the same submitter by grouping on ME001+ME107 and determine if a date of birth is present on one of the matching enrollment records. If so, use that date of birth for the member. Original note: SE’s often use default dates in dates of birth fields that can reveal illogical results in queries or analyses. The Arkansas APCD team does not clean or correct these data but allow the data user to work with the data to determine what is appropriate for their specific request. It is recommended to query the data first to identify what could be default dates. For example, if birth date is added to the query: SELECT t.birth_date,t.gender, t.MaxAge, COUNT(t.MaxAge) as CntOf FROM (SELECT ME001 AS EntityID,ME107 AS MemberID , [ME014] as birth_date, ME013 AS gender,MAX(me014_curr_age) AS MaxAge FROM [your dataset here].[dbo].[MEMBER] (this is the table name of my copy of the ABI dataset) GROUP BY ME001, ME107,[ME014], ME013) t GROUP BY t.birth_date,t.gender, t.MaxAge order by CntOf desc The top 3 rows reveal what could be default dates: birth_date gender MaxAge CntOf 1901-01-01 U 120 16340 1911-11-11 M 109 15300 1901-01-01 M 120 8918 It is recommended that you add other criteria such as enrollment dates (ME162A and ME163A) to support this assumption and make the best analytic decision. If your data has birth year instead of date of birth, use the same approach to identify out of range birth years. IMPORTANT: The APCD Unique ID (ME998) is comprised of the hashed, concatenated member last name and date of birth. If the date of birth is a default date, the APCD Unique ID will contain the default date and not the member’s date of birth and could negatively affect grouping member records. See https://achiapcd.atlassian.net/wiki/spaces/ADRS/pages/406847537/Tip+APCD+Unique+ID?src=search |