Westen, D., Shedler, J., Bradley, B., & DeFife, J. (2012). An empirically derived taxonomy for personality diagnosis: Bridging science and practice in conceptualizing personality. American Journal of Psychiatry, 169, 273-284.
Westen, D., Waller, N. G., Shedler, J., & Blagov, P. (2014). Dimensions of personality and personality pathology: Factor structure of the Shedler-Westen Assessment Procedure-II (SWAP-II). Journal of Personality Disorders, 28(2), pp. 281–318, 2014
OK, I have to fess up to bias and vindication when I am reading these two articles. I teach graduate students personality theory every year. These students are all clinicians, so I am really trying to prepare them for clinical practice, and it is my firm belief that clinically derived descriptions of personality styles are much more useful than those that emerge from other traditions – the five factor model in particular. So I assign ancient readings: Allport and Shapiro are, I believe, among the most useful – to expose them to clinical writings – empirically derived clinical writings – that describe clinical syndromes in ways that are coherent and hang together in my lived experience and, I hope, prepare them to use the diagnostic tools – the MMPI, MCMI, Rorschach, etc. that I believe to be bedrock tools in a clinician’s toolbox.
As long as I have been teaching I have gotten grief about this. Some of my students see me as being hopelessly out of step, and there is almost constant concern that they are not learning enough about the five factor model – the model that claims universality in personality assessment. I just don’t find that model to be as useful when trying to describe clinical populations and when trying to determine what sorts of interventions to engage in that will be useful to those who present for treatment. The five factor model is an impressive achievement and has given us an important and useful tool to compare the personality functioning of individuals across cultures and to better understand important elements in the personality functioning of the “normal” human being.
One of my concerns about the five factor model is that it seems to have grown, despite some protestations, out of a kind of mindless procedure – factor analysis. This procedure relies on linear algebra to produce clusters of variables that are inter-correlated and that, presumably, represent aspects of the same latent variable. In this sense, factor analysis mirrors psychoanalysis in that both use manifest data to make inferences about latent functioning. Why don’t I trust the procedure? Maybe it’s a little Hogwarts in me – Rowlings cautions us through one of her characters never to trust magic when you can’t see the magician creating it.
So imagine my surprise that these two papers, using factor analytic techniques, support the existence of independent diagnostic entities that sound familiar to me in the clinical setting. I think there are a number of reasons for this, but the first is the instrument that is used. Instead of a self report instrument that, as the authors propose, “…presupposes that (a) the data necessary and sufficient to derive a comprehensive and clinically relevant model of personality do not require expertise in psychopathology; (b) individuals with significant personality pathology have sufficient self-awareness and insight that their self-reports (or those of untrained peer observers) are sufficient to derive a comprehensive model of personality and its pathology; and (c) that the language of lay observation (or attempts to summarize it via factor analysis) is adequate for a diagnostic manual intended to be useful to both clinical practitioners and psychopathology researchers” (Westen et al., 2014, p. 282 -283), the SWAP is a clinician rating of the functioning of the patients.
I think the second reason is that Westen and his colleagues (2014) are using the factor analysis to serve their own needs, not the other way around. They do multiple factor analyses of the data, not a single one, and find the model that most closely fits their expectations of what psychopathology looks like. I think it is also possible that the correlations work out the way that they do because the clinicians have in mind the diagnostic categories that show up (in other words, the factor analysis is a measure of whether the clinicians were paying attention when they were taught psychodiagnosis and are finding what they were told they would – a long and pernicious problem in psychology). While I don’t doubt that this last factor accounts for some percent of the variance, Westen went to great trouble to recruit raters from a wide variety of backgrounds and chose the items for the instrument from a wide variety of sources. This is not just rigging the data to get the desired result.
So what are the results? When clinicians use the SWAP- 200, or in the case the new iteration, the SWAP –II, to rate the functioning of their patients, they rate each of 200 items on a Likert scale from 0 (not characteristic of the person) to 7 (highly characteristic of the person). They are forced to rate each of the eight descriptors a certain number of times, approximating a normal curve (or actually half of one, 100 items are required to be rated 0 as not characteristic). The items are not simple sixth grade reading items, but complicated descriptions of various aspects of personality functioning, e.g., “Appears to gain pleasure or satisfaction by being sadistic or aggressive toward others (whether consciously or unconsciously).”
The two papers report on two different ways of factor analyzing the data. In the first paper (Westen, et al., 2012), a hierarchical factor analysis groups factors into four categories: Internalizing functioning, Externalizing functioning, Neurotic functioning, and Healthy functioning. Within those categories, factor analyses are performed, with the Internalizing category including depressive, anxious avoidant, dependent victimized, and schizoid – schizotypal factors; the Externalizing category including antisocial, paranoid, narcissistic and borderline factors; the Neurotic including obsessional and hysteric/histrionic and the Healthy including one factor that is based on the items indicating psychological health. A similar group of factors emerge from the second paper (Weston, et al., 2014). In both papers, clinically cogent factors emerge: factors that mirror the experience of diagnosing the underlying personality styles of people presenting in clinical settings.
The inability of the DSM-V group to settle on a model for personality pathology indicates that we don’t have consensus about how best to understand the structure of people – the structure that supports the maladaptive difficulties that they present to us with and would like our help addressing. I think this may, ironically, be an indication of the advances that we are making – we have a variety of perspectives that are demonstrating integrity in the description of personality functioning. They are inconsistent with each other and none of them have coalesced as crisply and cogently as we would like. Would that the psychological world were divided as crisply and evenly as Shapiro (1965) thought that it would be. People are messier than that. Describing their functioning requires caveats and is, at best, a way of locating them at a particular moment in time and identifying characteristic, but certainly not the only ways, that they function, especially in particular kinds of settings.
The hopeful part is that there is order to the mess. There may be other models that are useful, but certainly the tried and true, the models that have been created by thoughtful people closely observing the functioning of others is supported in ways that will, I think, help us both in the clinical world of assessment and treatment, but also in that broader world that Freud dreamed of – a science of human functioning more generally.
Shapiro, D. (1965). Neurotic styles. New York: Basic Books.
If you are interested in responding to this post, please do so below. If you have read a research article recently that you think would be of interest to an audience of clinicians and would like to write a 1000- 1500 word summary of that, please send it as an email attachment to Karl Stukenberg at email@example.com. Include the words “Clinicians Reading Research” in the subject line.