Neuroticism (N) is a powerful correlate and predictor of many forms of psychopathology. This has prompted many to consider neuroticism an informative causal risk factor for psychopathology. However, this assumption may be flawed and reflect a misunderstanding of the nature of N-measures.

To establish the etiological meaning of the neuroticism-psychopathology association.

Review of relevant literature.

1. (1) The item content of N-measures is similar to (subthreshold) symptoms of psychopathology, especially internalizing disorders.

2. (2) Although N-scores strongly predict mental disorders adequate control for baseline symptoms and earlier episodes is typically lacking.

3. (3) Across adulthood, N-scores and psychiatric symptoms show a similar longitudinal pattern of decreasing differential stability with time, although the stability of N-scores is slightly higher.

4. (4) Differential consistency of both N-scores and psychopathology tend to drop over time, but do approach zero.

5. (5) The genetic influences on N and psychopathology substantially overlap and they share important environmental determinants.

6. (6) N-scores are heterogeneous in terms of lower-order traits, their manifestation in everyday life emotional processes, and innate versus acquired origins.

7. (7) N-scores reflect person-specific negative affect set points.

The prospective neuroticism-psychopathology association is largely non-causal and etiologically non-informative. The great utility of N-measures is that they index risk. In stead of considering high N-scores a causal risk factor that explains psychopathology, high N-scores are better conceptualized as a dependent variable in need of explanation. To become etiologically informative, elucidation of the basis and determinants of N is necessary.