Depression Dimensions: Integrating Clinical Signs and Symptoms from the Perspectives of Clinicians and Patients

<div><p>Background</p><p>Several studies have recognized that depression is a multidimensional construct, although the scales that are currently available have been shown to be limited in terms of the ability to investigate the multidimensionality of depression. The objective of this study is to integrate information from instruments that measure depression from different perspectives–a self-report symptomatic scale, a clinician-rated scale, and a clinician-rated scale of depressive signs–in order to investigate the multiple dimensions underlying the depressive construct.</p><p>Methods</p><p>A sample of 399 patients from a mood disorders outpatient unit was investigated with the Beck Depression Inventory (BDI), the Hamilton Depression Rating Scale (HDRS), and the Core Assessment of Psychomotor Change (CORE). Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA) were used to investigate underlying dimensions of depression, including item level analysis with factor loadings and item thresholds.</p><p>Results</p><p>A solution of six depression dimensions has shown good-fit to the data, with no cross-loading items, and good interpretability. Item-level analysis revealed that the multidimensional depressive construct might be organized into a continuum of severity in the following ascending order: sexual, cognitive, insomnia, appetite, non-interactiveness/motor retardation, and agitation.</p><p>Conclusion</p><p>An integration of both signs and symptoms, as well as the perspectives of clinicians and patients, might be a good clinical and research alternative for the investigation of multidimensional issues within the depressive syndrome. As predicted by theoretical models of depression, the melancholic aspects of depression (non-interactiveness/motor retardation and agitation) lie at the severe end of the depressive continuum.</p></div

Exploratory Factor Analysis (EFA) <i>eigenvalues</i>.

<p>Legend: Horizontal axis: number of factors; vertical axis: factor <i>eigenvalues</i>. The six-factor solution provided the most parsimonious and interpretable description.</p

Socio-demographic and clinical characteristics of the sample (n = 399).

<p>Legend: BDI, 21-item Beck Depression Inventory; HDRS, 17-item Hamilton Depression Rating Scale; CORE, Core Assessment of Psychomotor change.</p><p>Socio-demographic and clinical characteristics of the sample (n = 399).</p

Exploratory Factor Analysis six-factor solution.

<p>Legend: HAM, 17-item Hamilton Depression Rating Scale; BDI, 21-item Beck Depression Inventory; CORE, Core Assessment of Psychomotor change. The items that did not enter the models by Uher and Parker are coded in the “none” item dimension category.</p><p>Exploratory Factor Analysis six-factor solution.</p

Confirmatory Factor Analysis with factor loadings and response option thresholds.

<p>Legend: HAM, 17-item Hamilton Depression Rating Scale; BDI, 21-item Beck Depression Inventory; CORE, Core Assessment of Psychomotor Change; Loc, items locations; R2, squared factor loading (proportion of variance in that indicator variable explained by the factor).</p><p>Confirmatory Factor Analysis with factor loadings and response option thresholds.</p