Power BI model

Hi Alexh84 

Your setup:

• Referral Table (Referral ID is unique — 1 side)

• Reported Outcomes Table (Multiple rows per Referral ID — many side)

Relationship:

Referral (1) ----> (Many) Reported Outcomes

Get the first completed outcome:
First Outcome Completed =
CALCULATE(
MIN('Reported Outcomes'[Outcome Completed Date]),
'Reported Outcomes'[Referral ID] = SELECTEDVALUE('Referral'[Referral ID])
)
or if you want the corresponding outcome value:
First Outcome Name =
VAR FirstDate =
CALCULATE(
MIN('Reported Outcomes'[Outcome Completed Date]),
'Reported Outcomes'[Referral ID] = SELECTEDVALUE('Referral'[Referral ID])
)
RETURN
CALCULATE(
MAX('Reported Outcomes'[Outcome Name]),
'Reported Outcomes'[Outcome Completed Date] = FirstDate,
'Reported Outcomes'[Referral ID] = SELECTEDVALUE('Referral'[Referral ID])
)

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