|Richard E. Nisbett, Ph.D.|
Ecological Momentary Assessment (EMA) is a research technique designed to look at behavior and internal processes outside of the confines of what is called retrospective reporting. Retrospective reporting is the subjects' response to questionnaires about the way they normally respond in their daily lives - in hindsight.
- Patients with BPD have been invariably lying through their teeth - on an impossibly consistent basis - in giving even superficial descriptions of their personal symptoms and experiences during diagnostic interviews ever since the syndrome was first recognized, or
- The experimenters in the various earlier studies were lousy diagnosticians and were not applying the criteria in a valid manner.
Another issue is that, even if the diaries did ask about stressful interactions with intimates, and even if patients described them honestly and included their own behavior in their descriptions, the experimenters would still be in the dark about how severely stressful they were. That is because these interactions have subtexts, as I described in my post The Obvious Secret of Interpersonal Interactions Within Families.
Words and behaviors during family interactions take on additional shades of meanings within the context of all prior interactions, and these meanings can significantly add to the stress level of the involved parties. In fact, without knowing the entire history of the patient's family interactions, the experimenter's judgments about the severity of the stress would by necessity be extremely flawed.
As far as I know, there is only one method by which a mental health professional can obtain this data: long term psychotherapy with the involved individual. This should also include occasional conjoint sessions with the patient and family members, to get their sides of the story. The stressors of every single patient have qualities that are unique to them.