Description

The Depression Scale-Revised (DS-R-20) is a psychometric tool designed to assess symptoms of depression in adults. The DS-R-20 is a revision of the original Center for Epidemiological Studies Depression Scale (CES-D) and includes questions that measure the frequency and intensity of depressive symptoms such as sadness, loss of interest in activities, changes in appetite or sleep, and feelings of hopelessness.
The DS-R-20 typically includes 20 items, which are rated on a Likert scale that measures the frequency of symptoms over the past two weeks. Respondents are asked to select from options such as “never,” “sometimes,” “often,” etc., to describe how frequently they have experienced each symptom.

Data Analysis and Usage

Data analysis from the DS-R-20 involves the following procedures:
Descriptive Statistics:
Means and Standard Deviations: Calculation of means and standard deviations for responses to each question or for the total scale score.
Reliability:
Assessment of the internal consistency of the scale through Cronbach’s alpha to confirm the reliability of the results.
Correlations:
Examination of correlations between scores on different questions to understand relationships between various aspects of depressive symptoms.
Factor Analysis:
Use of factor analysis to identify key factors contributing to depressive symptoms if necessary.

Purpose

The main purpose of the DS-R-20 is to provide a reliable tool for assessing depressive symptoms. It is used for:
Research Purposes: Studying the prevalence and severity of depressive symptoms across various populations and their effects on psychological and social levels.
Clinical Evaluation: Assessing depression in a clinical setting for diagnosis and monitoring patient progress.
Policy and Strategy: Developing policies and strategies for the prevention and intervention of mental health issues.

Calibration

Calibration of the DS-R-20 involves analyzing the data obtained from using the scale:
Internal Consistency Assessment: Calculation of the reliability of the tool through Cronbach’s alpha to ensure the consistency of responses.
Comparative Analysis: Comparing results with data from other relevant studies to confirm the validity and reliability of the scale.

Bibliography

Radloff, L. S. (1977). The CES-D Scale: A Self-Report Depression Scale for Research in the General Population. Applied Psychological Measurement, 1(3), 385-401.
Eaton, W. W., Muntaner, C., Smith, C., Tien, A., & Ybarra, M. (2004). Center for Epidemiologic Studies Depression Scale: Review and revision (DS-R-20). In J. P. Robinson, P. R. Shaver, & L. S. Wrightsman (Eds.), Measures of Personality and Social Psychological Attitudes (pp. 363-377). Academic Press.
Van Dam, N. T., & Earleywine, M. (2011). The Center for Epidemiologic Studies Depression Scale: Review and Revision (DS-R-20). In L. J. DeRubeis & J. E. Hollon (Eds.), The Oxford Handbook of Depression and Comorbidity (pp. 210-223). Oxford University Press.