Isabel DDx Companion

Expand your differential diagnosis and gain reassurance in your decision making.


Isabel is the leading differential diagnosis generation tool trusted by hundreds of institutions and thousands of clinicians every day. The DDx Companion covers over 10,000 conditions, all ages and specialties and delivers an accurate differential in less than 90 seconds!

Isabel’s unique AI technology based on machine learning, means that a list of likely diseases can be instantly generated using just the presenting clinical features and without having to answer endless questions.

The most important aspect of Isabel’s technology is how well it was trained over 22 years using evidenced-based knowledge and feedback from practicing clinicians about how diseases present. This training is underpinned with a continual validation process and enables Isabel to suggest the correct disease in the top ten differential with 96% accuracy!

No human can recall the volumes of typical and atypical ways that all diseases present – let alone when tired and in a noisy, high-pressure environment. Isabel can serve as your safety net and ease the pressure by helping broaden your differential with even the most atypical or complex cases.

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Interested in how Isabel can benefit your organization and want more information? Sign up for an informative demonstration and discussion with an Isabel team member.

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How it works

To start, enter the patient’s demographics and presenting clinical features. You can either pick from the drop-down list of over 25,000 autocomplete phrases or enter free text. Even complex cases can be processed with unlimited clinical features including lab / imaging results, co-morbidities and other risk factors if you consider them relevant. Isabel utilizes specialized algorithms to present only results relevant to the patient’s age, sex and region.

The results are ranked using a relevance match based on matching of terms in the Isabel database of typical and atypical disease presentations, this is reflected in a colored likelihood bar to help you quickly focus on the most important diseases for consideration. The red flags highlight the ‘don’t miss’ diseases that could cause patients severe harm if not treated quickly. You can quickly sort the list by speciality or ‘don’t miss ’diseases.

The ‘Drugs’ feature also enables you to instantly check for a list of medications that could be the cause of your patients’ symptoms.

The Isabel DDx Companion is now established as the benchmark for differential diagnosis tools because it has been trained and undergone continuous testing, tuning, validation and clinician feedback over 22 years.

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Next Steps with Evidence-Based Knowledge

Isabel partners with major medical publishers providing evidence-based knowledge about each disease so you can quickly read about the other signs and symptoms you should be checking for, first line tests to order and explore treatment protocols. Our long-term partners include DynaMed® and DynaMedex from EBSCO, 5 Minute Consult™ from Wolters Kluwer and Best Practice from the BMJ.

Build Isabel DDx into your workflow

You can enter the clinical features into the DDx Companion manually as easily as using Google or the tool can be integrated with your Electronic Medical Records (EMR) using our API allowing the clinical features to be extracted automatically.

Isabel DDx is currently available in the Cerner App Gallery and Epic clients can have info-button access to put Isabel into the hands of clinicians using the EMR.

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Sign up for a free 30-day trial of the Isabel DDx Companion!

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