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Rare Disease Terminology & Definitions - A Systematic Global Review:
Report of the ISPOR Rare Disease Special Interest Group

Rare Disease Terminology & Definitions - A Systematic Global Review: Report of the ISPOR Rare Disease Special Interest Group

The citation for this report is:
Richter T, Nestler-Parr S, Babela R., et al. Rare Disease Terminology & Definitions - A Systematic Global Review: Report of the ISPOR Rare Disease Special Interest Group. Value Health 2015; 18:906-14.

Developed by the ISPOR Rare Disease Special Interest Group


Dyfrig Hughes, PhD, MSc, Professor, Centre for Health Economics and Medicines Evaluation, Bangor University, Wales, UK
Zeba M. Khan, RPh, PhD, Vice President, Strategic Market Access & Policy, Celgene Corporation, Summit, New Jersey, USA

Leadership Group:

Robert Babela, PhD, MSc, Head of Department of Public Health / HM, St. Elizabeth University, Bratislava, Slovakia
Sandra Nestler-Parr, PhD, Mphil, Head of Rare Diseases, Roboleo & Co, London, England, UK
Trevor Richter PhD, MSc, BSc, Research Manager, Health Economics, Canadian Agency for Drugs and Technologies in Health (CADTH)Ottawa, ON, Canada


North America: USA & Canada
Central & South America: Argentina, Brazil, Chile, Columbia, and Mexico
Europe: Czech Republic, Denmark, France, Germany, Ireland, Italy, The Netherlands, Poland, Russia, Slovakia, Spain, Sweden, Turkey, United Kingdom, England, Scotland, Wales plus the European Union
Asia–Pacific: Australia, China, India, Japan, Korea, and Taiwan
Africa: South Africa

Rare Disease Terms

Rare disease(s)
Rare disorder(s)
Rare condition(s)
Neglected disease(s)
Orphan disease(s)
Orphan subset

Syndrome(s) without a name
Rare and neglected disease(s)
Undiagnosed disease(s)
Ultra-orphan disease(s)
Ultra-rare disease(s)
Very rare disease

Highly specialised technologies
Orphan drug(s)
Orphan medicinal product(s)
Orphan product(s)
Ultra-orphan drug(s)


Rare Disease: Terminology & Definitions Around the World
May 2011 - ISPOR 16th Annual International Meeting, Baltimore, Maryland, USA

Rare Diseases: Terms, Definitions, and Challenges in Assessing and Appraising Diagnostics and Treatments
November 2013 - 16th Annual European Congress, Forum Presentation, Dublin, Ireland


We are sincerely grateful to the following ISPOR members who generously gave their time and shared their expertise to conduct the jurisdiction-specific research that made this study possible. (The jurisdiction for each individual who provided research data is given in parentheses.): Ceren Akdere, BSc, MSc (Turkey); Amílcar Azamar Alonso, MSc (Mexico); Gabriela Tannus Branco de Araujo, MSc (Brazil); Henk Broekhuizen, MSc (The Netherlands); Paolo A. Cortesi, PhD (Italy); Dalia Dawoud, BSc, MSc, PhD (Denmark); Melike Deger, MSc (Turkey, Australia); Mitchel van Eeden (The Netherlands); Brenda Dooley, MSc, BA (Ireland); Manuel Espinoza MD, MSc, PhD (Chile); Ruediger Gatermann, MA, MBA (Germany); Dominik Golicki, PhD, MD, MSc (Poland); Tim Kanters, MSc (The Netherlands); Katarzyna Kolasa, MSc (Poland, Sweden); Daria Korchagina, MBE (Russian Federation); Katerina Kubackova, MD, PhD (Czech Republic); Yukiko Nishimura, MSc (Japan); Hye-young Kwon, PhD (South Korea); Camila Ignacia Quirland Lazo, BS (Chile); Rony Lenz, MA (Chile); Shelley McGee, MSc, BSc (South Africa); Milan Macek, MD, PhD (Czech Republic); Andrea Marcellusi, MSc (Italy); Sandra Milev, MSc (Canada); Giácomo Balbinotto Neto, PhD (Brazil); Liv Nymark, BSc, MSc (Denmark); Xiongfei (Steven) Pan (China); Pedro Plans, MD, MBA, MSc (Spain); Marcelo Ponte, MD (Argentina); Jonathan Rodrigues, PharmD (France); Diego Rosselli, MD, MSc, Med (Colombia); J.L. (Hans) Severens, PhD (The Netherlands); Petra Szilagyiova, MD (Slovakia); Jun Tang, PhD (China); Tomas Tesar, PhD, MBA (Slovakia); Dixon Thomas, MPharm, MS, MSc, PhD (India); Weiying Wang, MPH (India, USA); Ramon Wiest, BSc (Brazil); Johanna Wiss, (Sweden); Danny Yeh, PhD (Taiwan). Our thanks also to the following members of the ISPOR Rare Disease Terminology & Definitions Used in Outcome Research Working Group who contributed to the development of this manuscript: Ruzan Avetisyan, PhD, MD; Bryan Bennett, PhD, BSc; Jacqueline Bowman-Busato; Dalia Dawoud, BSc, MSc, PhD; Melike Deger; Brenda Dooley, MSc, BA; Meg Franklin, PharmD, PhD; Vivian Herrera; Katarzyna Kolasa; Zoltán Kaló, PhD, MD, MSc; Yasufumi Kuroda, PhD; Zhimei (Jamae) Liu, PhD; Sandra Milev, MSc; Andrew Olaye, PhD; Phil Ruff, PhD, BSc; Ruth Suter, MBA, RD; Vlad Zah, PhD, BSc. Finally, we are grateful to each of the following reviewers who submitted written comments on a draft version of this manuscript: Bhagwan Aggarwal; Renée J.G. Arnold; Ségolène Aymé; Suresh Bastakoti; Katy Benjamin; Audra Boscoe; Caroline Conti; Hugh Dawkins; Dalia Dawoud; Jenifer Ehreth; Eileen Fonseca; Ruediger Gatermann; Michael A. Hagan; Uchenna Iloeje; Pravin S. Kamble; Henry Komakech; Yasufumi Kuroda; Hui-Chu Lang; Lars-Åke Levin; Nishkarsh Likhar; Andriy Moshyk; Yukiko Nishimura; Pedro Plans; Jonathan Rodrigues; Karina Różyk; Philip W. Ruff; Luciana Scalone; Neil M. Schultz; Lesley Shane; Ajit Singh; Ruth Suter; Naoko Tomita; Nicolas Vargas Zea; Durhane Wong-Rieger; Vlad Zah; Arthur S. Zbrozek.

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