About DRG Epidemiology

DRG’s Epidemiology provides bottom-up, patient-level forecasts, detailing disease trends from 10- to 20-year outlook periods to help you validate investments and identify growth opportunities in your markets of interest.

All of our epidemiological data, methods and insight are distributed via DRG’s Insights Platform, allowing the user to easily navigate between world regions and patient populations, as well as download epidemiological forecast data into an MS Excel format for offline use.

All epidemiological forecasts may be supplemented with custom deliverables, such as:

  • Chart reviews or more granular stratification using DRG’s in-house real world datasets or physician survey data.
  • Customized and interactive patient flow models or additional subpopulations or metrics.
  • Expanded geographical coverage or extended forecast periods beyond those available.


Our robust patient population sizing data include therapeutic coverage of 140+ indications and 3,400+ patient subpopulations, including extensive oncology subpopulation data by stage, line of therapy, and biomarker, as well as continually expanding niche and rare disease coverage.

The geographic breadth of data includes mature-market (G7) reporting for all 140+ indications, as well as 90% global population coverage for the high-profile diseases, and expanded penetration for emerging and rest-of-world markets in select indications.


For more than 20 years, our data and methodology have been developed and refined by DRG’s Epidemiology team of industry-leading subject matter experts, driven by rigorous methodology to uncover the impact of exposure, risk, and treatment, in addition to historical trends and age and gender cohorts.

All of our epidemiological forecasts are accompanied by a transparent description of our methods and data sources, the details of our systematic review underlying each forecast and associated summary evidence tables, and access to the authoring epidemiologist.

Table of contents

  • Persistent Depressive Disorder - Epidemiology - Mature Markets
    • Introduction
      • Key Findings
      • Total Prevalence of Persistent Depressive Disorder per 1,000 Among People Aged 15+ in 2020 and 2040
      • Relative Sizes of the Factors Contributing to the Trend in Total Prevalent Cases of Persistent Depressive Disorder over the Next Twenty Years
    • Epidemiology Data
    • Methods
      • Total 12-Month Prevalent Cases
    • Reference Materials
      • Literature Review
        • Studies Included in the Analysis of Persistent Depressive Disorder
      • Risk/Protective Factors
        • Risk/Protective Factors for Persistence Depressive Disorder
      • Bibliography
      • Glossary

Author(s): Shilpa Thakur; Swarali Tadwalkar

Shilpa Thakur, M.P.H., is an associate epidemiologist at DRG, part of Clarivate. Before joining DRG, she monitored HIV sentinel surveillance in Himachal Pradesh. She has also studied the patterns of antimicrobial resistance in India. She received her M.P.H. from the Postgraduate Institute of Medical Education and Research with a specialization in epidemiology and biostatistics.

Swarali Tadwalkar, M.P.H., is a senior epidemiologist at DRG, part of Clarivate. Prior to joining DRG, she was involved in primary and secondary healthcare research, including projects in digital health, health policy and management, and health economics and outcomes research (HEOR). Ms. Tadwalkar also coordinated various nongovernmental public health projects focusing on access to treatment for hepatitis and human papilloma virus. She received her M.P.H. from the University of South Florida in Tampa.