@juliowastaken - you're missing a comma.
If(
dpSPSelectStudy.Selected.Value = "ASPIRE" || dpSPSelectStudy.Selected.Value = "DETECT" || dpSPSelectStudy.Selected.Value = "SOFAST",
true,
false
)
On a related note, depending on what you're trying to do, you do not need to wrap an IF function around a formula which is already going to return a boolean anyway. For example, the below will return the same output:
dpSPSelectStudy.Selected.Value = "ASPIRE" || dpSPSelectStudy.Selected.Value = "DETECT" || dpSPSelectStudy.Selected.Value = "SOFAST"
As will this:
dpSPSelectStudy.Selected.Value in [
"ASPIRE",
"DETECT",
"SOFAST"
]