Depression Sub-Typing: Unitary, Binary or Arbitrary?

The strongest statistical support for the binary view of depression has been provided by factor (principal components) analytic studies which delineate a bipolar factor with features interpreted as reflecting "endogenous depression" and "neurotic depression" at opposing poles. We review the seminal studies to suggest instead that the bipolar factor has generally polarised depression and anxiety, and that no such entity or symptom complex of...