Replace blanks with a dash without ignoring filters

[mariahMC]

I have an average measure that averages answers to questions (yes = 1, no =0). My matrix visual shows averages for each question over 4 Quarters and is filtered by procedure type. Some quarters may have blank values for certain questions and instead of showing blank I want to show a dash "-". However, when I try to use an IF statement, it ignores my filters and shows all the questions regardless of the procedure type selected.

My average measure:

Average Score = AVERAGE('Reviews'[Binary])

Here are my attempts at replacing the blanks with a dash:

AvgScoreBlank = IF(ISBLANK([Average Score]),"-",[Average Score])

//Puts "-" in blank values, but ignores filter

AvgScoreBlank = IF([Average Score]=BLANK(),"-",[Average Score])

//Puts "-" in blank values, but ignores filter

AvgScoreBlank = IF(NOT(ISBLANK([Average Score])),SWITCH(TRUE(), [Average Score]=0, "-",[Average Score]))

//Puts "-" in zero values but not in blank values

[Greg_Deckler]

@mariahMC Try: AvgScoreBlank = IF([Average Score]=BLANK(),"-",[Average Score] & "")

[mariahMC]

@Greg_Deckler unfortunately, that didn't work and it turned the average values into text 

[Greg_Deckler]

@mariahMC Yeah, that's kind of the point, DAX doesn't like measures returning variant data types like sometimes numbers and sometimes text. You could do this:

Try: AvgScoreBlank = IF([Average Score]=BLANK(),"-",FORMAT( [Average Score], "Percent"))

You could also try measure conditional formatting but I believe that's preview.

[mariahMC · Accepted solution]

@Greg_Deckler I found a solution that works

AvgScoreBlank =

IF( NOT ISEMPTY('Reviews'),COALESCE([Average Score],"-"))

[mariahMC]

@Greg_Deckler The measure AvgScoreBlank = IF([Average Score]=BLANK(),"-",[Average Score]) works as intended, the issue is that it's ignoring my slicer filter. When I select a procedure type from the slicer, it should only show the questions and averages relevant to that procedure, however the AvgScoreBlank measure is showing all questions with blank values.