Development of the International Severe Asthma Registry (ISAR): a modified Delphi study

The story of this publication began several years ago when a group of like-minded asthma experts thought it would be rather a good idea to pool national resources and collect information on severe asthma in a single global registry. Simple, right?! Fast-forward a few months and the International Severe Asthma Registry (ISAR; was born.

The concept of ISAR is simple”, explains Prof David Price (Co-founder of ISAR), “to open national/regional severe asthma registry borders and pool our data to generate a centralized severe asthma dataset. The resulting dataset would be the first global adult severe asthma registry in the world, permitting seamless information sharing between countries, and ultimately giving us a better insight into severe asthma on a global scale.

However, before ISAR could be built, the experts had to agree on a standardized list of variables to collect. And so the fun commenced! It was decided to use a modified Delphi process to reach consensus on a minimum set of variables to capture in ISAR.

Looking back, remarks Prof Price, “I’m really proud of what we managed to achieve. The Delphi panel consisted of 27 international experts in the field of severe asthma research; the process involved 3 iterative rounds; and from an initial 747 identified variables we agreed to collect 95 standardized core variables in ISAR.”

These variables cover patient details and medical history, co-morbidities, blood and sputum biomarkers, diagnostics, lung function, allergen testing, asthma control, medication, adherence and management plans. The full list is provided in the published article. ISAR is now fully operational and growing all the time. It currently contains longitudinal, real-life, standardized, high quality data on 5892 patients from 14 countries in Europe, North America, Middle East and Asia-Pacific and, continues to grow.

It’s been an exciting time in the field of severe asthma, says Prof Price. We’ve taken our first peek at the global severe asthma population, and due to standardization of variables across registries have been able make meaningful cross country comparisons in epidemiology, types of asthma and management practices. The sheer size of ISAR means that we will have sufficient statistical power to answer research questions, which until now have been beyond our grasp; questions like ‘who will respond best to treatment?’, and ‘who is likely to develop severe asthma?’. ISAR may also help us to identify new treatment targets, investigate the effectiveness of novel approaches and the feasibility of new asthma treatment paradigms.

ISAR is conducted by Optimum Patient Care Global Limited. OPC Global and AstraZeneca co-sponsor the initiative, and together with the Respiratory Effectiveness Group, ensure ISAR research is ethical, clinically appropriate and continues to bring genuine value to patients, public health, and healthcare.