DDx vs WorstFirst

DDx is a fast, offline differential diagnosis lookup tool — like a textbook in your pocket. Open any symptom and see a ranked list of diagnoses, with don't-miss conditions surfaced first. Built for medical students, residents, and clinicians who want a no-frills educational reference at the bedside. In the same category as Diagnosaurus. WHAT'S INSIDE • 375 symptoms across 17 body systems • 6,148 differentials, ranked by probability and urgency • Don't-miss diagnoses highlighted in red • ICD-10 codes for the most common conditions • Search by symptom name, synonym, ICD-10, or diagnosis • Generated PubMed search references on every diagnosis • Bookmark symptoms for quick recall Unlock the workflow tools that keep you moving fast: • Five clinical scoring calculators — HEART (chest pain risk), Wells (DVT pre-test probability), PERC (PE rule-out), CURB-65 (pneumonia severity), Modified Centor (strep pharyngitis) • Reverse condition lookup — find every symptom a diagnosis can present with • Patient-context filters — age and sex chips on every symptom • All future content and feature updates included The core differential diagnosis lookup stays free, forever. DESIGNED FOR THE BEDSIDE • Built for iPhone and iPad with full Dark Mode — true near-black for dim wards • Triage-board layout: hairline rules, ranked numerals, urgency-only color • 100% offline after install — no account, no sign-up, no tracking, no ads • Universal app: one purchase covers iPhone, iPad, and Apple Vision Pro EDUCATIONAL REFERENCE — IMPORTANT DDx is an educational reference. It is NOT a medical device, does NOT provide individualized medical advice, and is NOT a clinical decision support system. The content is generated from medical literature and may contain inaccuracies. Always verify against primary sources. Any clinical action remains the sole responsibility of the qualified clinician caring for the patient. PRIVACY DDx never collects, transmits, or stores personal data. No account. No analytics. No tracking. Bookmarks live on your device only. LICENSE Use of DDx is governed by Apple's Licensed Application End User License Agreement: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

WorstFirst is a decision-tree training tool for emergency medicine trainees, built by a practicing emergency physician. Emergency medicine runs on one discipline: rule out the killers first. WorstFirst trains that instinct. Pick a chief complaint and work through a structured decision tree — the same worst-first reasoning used at the bedside — before settling on the benign explanation. WHAT'S INSIDE - 29 chief-complaint decision trees spanning cardiovascular, respiratory, neurologic, abdominal, trauma, tox, and more - Branch-by-branch reasoning with teaching pearls and common pitfalls - Citations to landmark literature and current guidelines throughout - Fully offline — no account, no sign-in, no data collection WHO IT'S FOR Medical students, EM residents, and other healthcare trainees building their approach to undifferentiated complaints. FOR EDUCATIONAL USE ONLY WorstFirst is an educational reference. It is not a medical device and is not intended to diagnose, treat, or guide the care of any patient. It must not be used for clinical decision-making. All content is for learning purposes only and does not replace clinical judgment, institutional protocols, current guidelines, or attending supervision.