Escitalopram versus nortriptyline: how to let the clinical GENDEP data tell us what they contained

The Hamilton Depression Scale (HAM-D) and the Montgomery-Åsberg Depression Scale (MADRS). A psychometric re-analysis of the European genome-based therapeutic drugs for depression study using Rasch analysis

The objective of this re-analysis of the European Genome-Based Therapeutic Drugs for Depression Study (GENDEP) was to psychometrically test the unidimensionality of the full Montgomery Åsberg Depression Rating Scale (MADRS10) and the Hamilton Depression Scale (HAM-D17) versus their respective subscales (MADRS5 and HAM-D6) containing the core symptoms of depression severity. Rasch analysis was applied using RUMM 2030 software to assess the overall fit for unidimensionality. Neither the MADRS10 nor the HAM-D17 was found to fit the Rasch model for unidimensionality. The HAM-D6 (containing the items of depressed mood, guilt, work and interests, psychomotor retardation, psychic anxiety, and somatic general) as well as the analogue MADRS5 were tested for unidimensionality by use of the RUMM 2030 programme, and only the HAM-D6 was accepted. When testing for invariance across rating weeks or centres, the RUMM 2030 had to be supplemented with the Friedman two-way analysis of variance by ranks. The HAM-D6 but not the MADRS5 was accepted. It was therefore concluded that the HAM-D6 is a psychometrically valid outcome scale to measure change in clinical trials of antidepressants.

Brief, unidimensional melancholia rating scales are highly sensitive to the effect of citalopram and may have biological validity: implications for the research domain criteria (RDoC)

BACKGROUND

Most depression rating scales are multidimensional and the resulting heterogeneity may impede identification of coherent biomarkers. The aim of this study was to compare the psychometric performance of the multidimensional 17-item Hamilton Depression Rating Scale (HAM-D17) and the 30-item Inventory of Depressive Symptomatology (IDS-C30) to that of their unidimensional six-item melancholia subscales (HAM-D6 and IDS-C6).

METHODS

A total of 2242 subjects from level 1 (citalopram) of the Sequenced Treatment Alternatives to Relieve Depression (STAR* study were included in the analysis. Symptom change, response and remission rates were compared for HAM-D6 versus HAM-D17 and for IDS-C6 versus IDS-C30. The changes in total scores on these scales were compared to the change in Quality of Life Enjoyment and Satisfaction Questionnaire (QLES-Q) score using correlation analysis.

RESULTS

The response to treatment was significantly greater according to the HAM-D6 and IDS-C6. Furthermore, the correlation of changes in depression-ratings with changes in QLES-Q scores were comparable for the subscales and full scales.

LIMITATIONS

STAR*D was not designed to answer the research questions addressed in this analysis.

CONCLUSIONS

Our findings indicate that the HAM-D6 and IDS-C6 melancholia scales capture a coherent construct in depression. The syndrome reflected in these scales is unidimensional, sensitive to specific pharmacological intervention, and therefore likely to have biological validity. We therefore believe that "melancholia" thus defined could be a valuable construct under the Research Domain Criteria (RDoC), which specifically aims at identifying the neurobiology underlying mental disorders and providing drugable targets.

Measuring psychotic depression

OBJECTIVE

Psychotic depression (PD) is a highly debilitating condition, which needs intensive monitoring. However, there is no established rating scale for evaluating the severity of PD. The aim of this analysis was to assess the psychometric properties of established depression rating scales and a number of new composite rating scales, covering both depressive and psychotic symptoms, in relation to PD.

METHOD

The psychometric properties of the rating scales were evaluated based on data from the Study of Pharmacotherapy of Psychotic Depression.

RESULTS

A rating scale consisting of the 6-item Hamilton melancholia subscale (HAM-D6 ) plus five items from the Brief Psychiatric Rating Scale (BPRS), named the HAMD-BPRS11 , displayed clinical validity (Spearman's correlation coefficient between HAMD-BPRS11 and Clinical Global Impression - Severity (CGI-S) scores = 0.79-0.84), responsiveness (Spearman's correlation coefficient between change in HAMD-BPRS11 and Clinical Global Impression - Improvement (CGI-I) scores = -0.74--0.78) and unidimensionality (Loevinger's coefficient of homogeneity = 0.41) in the evaluation of PD. The HAM-D6 fulfilled the same criteria, whereas the full 17-item Hamilton Depression Scale failed to meet criteria for unidimensionality.

CONCLUSION

Our results suggest that the HAMD-BPRS11 is a more valid measure than pure depression scales for evaluating the severity of PD.

The Symptom Checklist-core depression (SCL-CD6) scale: Psychometric properties of a brief six item scale for the assessment of depression

Aims: Major depressive disorders are common, with substantial impact on individuals/society. Brief scales for depression severity, based on a small number of characteristics all of which are necessary for diagnosis, have been recommended in self-reported versions for clinical work or research when aiming to quickly and accurately measure depression. We have examined psychometric properties of a brief 6-item version of the Symptom Checklist (SCL), the Symptom Checklist core depression scale (SCL-CD6) and aimed to identify a cut-point for epidemiological research. Methods: The psychometric evaluation of the SCL-CD6 was mainly performed by a Mokken analysis of unidimensionality in a random sample of 1476 residents in the Stockholm County, aged 18–64 years. The standardization of SCL-CD6 was based on ROC analysis, using the Major Depression Inventory as index of validity. Predictive validity was subsequently assessed using register data on hospital admissions and purchases of prescribed medications linked to a sample of 5985 participants in the Swedish Longitudinal Occupational Survey of Health (SLOSH). Results: The SCL-CD6 obtained a coefficient of homogeneity of 0.70 by Mokken analysis, which indicates high unidimensionality and a meaningful dimensional measure of depression severity. By ROC we identified a score of 17 or higher (total range 0–24) as the best cut-point for major depression (sensitivity 0.68, specificity 0.98) which predicted subsequent purchases of antidepressants as well as hospitalisations with a depressive episode. Conclusions: The SCL-CD6 was found a valid depression scale with higher unidimensionality than longer epidemiological instruments and thus particularly suitable for assessment in larger population surveys.