VT vs SPI: ARDMS Exam Comparison
This page compares the ARDMS Vascular Technology (VT) and Sonography Principles & Instrumentation (SPI) exams side by side. Both are ARDMS-administered specialty examinations, but they differ in clinical scope, content focus, career setting, and 2025 pass-rate data.
VT vs SPI: Exam Comparison
| Factor | Vascular Technology (VT) | Sonography Principles & Instrumentation (SPI) |
|---|---|---|
| Credential earned | RVT | RDMS/RVT prerequisite |
| Question count | 170 | 110 |
| Exam duration | 3 hours | 2 hours |
| 2025 first-time pass rate | 70% | 74% |
About the Vascular Technology (VT) Exam
The ARDMS Vascular Technology (VT) specialty exam earns the Registered Vascular Technologist (RVT) credential. It has the lowest first-time pass rate among all seven specialties (70% in 2025) and tests a deep understanding of hemodynamics, Doppler physics, carotid stenosis criteria, DVT protocols, peripheral arterial disease, and abdominal vascular assessment.
About the Sonography Principles & Instrumentation (SPI) Exam
The ARDMS Sonography Principles and Instrumentation (SPI) exam is the physics prerequisite required before earning any ARDMS specialty credential. It tests sound wave physics, transducer construction, image formation, ultrasound artifacts, Doppler principles, quality assurance, bioeffects, and ALARA safety principles. Unlike specialty exams, the SPI rewards an academic rather than clinical approach.
Which Exam Should You Take First?
The right choice depends on your clinical background, your current employer's needs, and your long-term career goals. Sonographers with strong clinical experience in vascular technology imaging should consider the VT exam first, as applied clinical knowledge transfers directly to board performance. Similarly, those working predominantly in sonography principles & instrumentation settings will find the SPI exam more immediately supported by their daily practice.
Both credentials are valuable additions to a multi-specialty credential portfolio. The 2025 first-time pass rates — 70% for VT and 74% for SPI — underscore the importance of structured, domain-aligned preparation for whichever exam you choose first.
Dig Deeper Into Each Specialty
- Vascular Technology (VT) exam prep · VT practice questions
- Sonography Principles & Instrumentation (SPI) exam prep · SPI practice questions
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