Heterogeneity in psychiatric diagnostic classification.

The theory and practice of psychiatric diagnosis are central yet contentious. This paper examines the heterogeneous nature of categories within the DSM-5, how this heterogeneity is expressed across diagnostic criteria, and its consequences for clinicians, clients, and the diagnostic model. Selected chapters of the DSM-5 were thematically analysed: schizophrenia spectrum and other psychotic disorders; bipolar and related disorders; depressive disorders; anxiety disorders; and trauma- and stressor-related disorders. Themes identified heterogeneity in specific diagnostic criteria, including symptom comparators, duration of difficulties, indicators of severity, and perspective used to assess difficulties. Wider variations across diagnostic categories examined symptom overlap across categories, and the role of trauma. Pragmatic criteria and difficulties that recur across multiple diagnostic categories offer flexibility for the clinician, but undermine the model of discrete categories of disorder. This nevertheless has implications for the way cause is conceptualised, such as implying that trauma affects only a limited number of diagnoses despite increasing evidence to the contrary. Individual experiences and specific causal pathways within diagnostic categories may also be obscured. A pragmatic approach to psychiatric assessment, allowing for recognition of individual experience, may therefore be a more effective way of understanding distress than maintaining commitment to a disingenuous categorical system.

Paper-and-pencil or online? Evaluating mode effects on measures of emotional functioning and attachment.

The viability of using the World Wide Web to collect data from three widely used instruments by clinicians and researchers was investigated. The instruments were the Inventory of Parental and Peer Attachment, the Negative Mood Regulation Scale, and the Trait Meta-Mood Scale. Data were collected from two comparable groups of college students, and differences in response patterns on paper-and-pencil and World Wide Web versions of the measures, at both the item level and scale score level, were documented. Although mode of administration effects were statistically significant, the magnitude of the effects was in general very small. The basic similarity of the properties of the measures using paper-and-pencil and online Internet modes of administration suggests the viability of the Internet for assessing these and other psychological phenomena.