i did the calculation once upon a time but i can't remember the outcome. i'd be interested to know the answer if anyone is good with combinatorial mathematics.

there are... 9 different symptoms of BPD. in order to meet criteria you need to have i think it is 5 out of those 9 symptoms.

so you could have 5 symptoms
or you could have 6 symptoms
or you could have 7 symptoms
or you could have 8 symptoms
or you could have 9 symptoms.

there is one way in which you can have all 9 symptoms.
there are nine ways in which you can have 8 symptoms.
there are xxx ways in which you can have 7 symptoms.
there are yyy ways in which you can have 6 symptoms.
there are zzz ways in which you can have 5 symptoms.

so 1+9+xxx+yyy+zzz= how many different ways someone can meet criteria for borderline personality disorder.

can't remember. 54? 256? 512?

so... there can be considerable diversity in the symptoms exhibited by people who present with borderline personality disorder.