CDN Cheat Sheet 2026: One-Page Review of Must-Know Facts

Exam Snapshot: The Numbers You Need Cold

Before you touch a single practice question, memorize the mechanics of the Certified Dialysis Nurse exam itself. The Nephrology Nursing Certification Commission (NNCC), working with the Center for Nursing Education and Testing (C-NET), administers the CDN credential through computer-based testing at PSI sites year-round. That means there's no single "test day" - you schedule when your eligibility window and study plan align.

Here's the one-page version of what matters:

For a deeper dive into how these numbers translate into a study strategy, see our full CDN Study Guide 2026. If you want the pass-rate context explained in detail, the CDN Pass Rate 2026 breakdown is worth bookmarking alongside this cheat sheet.

Domain Breakdown at a Glance

The CDN exam blueprint has four domains, and they are not weighted anywhere close to equally. This is the single most important structural fact on this entire page - it should shape every hour you spend studying.

Together, Domains 1 and 2 make up 84% of the scored content. If your study time isn't reflecting that ratio, you're studying the wrong exam. For a full walkthrough of every subtopic inside each domain, read the CDN Exam Domains 2026 guide.

Chronic HD Unit (ESRD): The 52% You Cannot Skip

Because this domain alone accounts for over half the exam, treat it as its own mini-certification. Expect scenario-based, four-option questions built around real unit situations rather than pure recall.

• Vascular access types (fistula, graft, catheter) and their complication profiles
• Dialysis adequacy measures and prescription adjustments
• Intradialytic complications: hypotension, cramping, disequilibrium syndrome
• Anemia management, mineral and bone disorder, and medication considerations specific to chronic HD patients
• Infection control and access-site care protocols
• Patient education and long-term care coordination for in-center hemodialysis patients

This domain also lines up directly with the experience requirement: eligibility demands 2,500 hours of nephrology RN experience specifically caring for in-center hemodialysis patients (or supervising/educating that staff). If your daily practice already lives in this domain, lean into that advantage rather than over-studying areas you rarely touch clinically.

Concepts of Kidney Disease in Adults

Domain 2 is where the exam tests whether you understand the disease process itself, not just the treatment unit. Expect questions on:

• CKD staging and progression markers
• Comorbid conditions - diabetes, hypertension, cardiovascular disease - as CKD drivers
• Fluid and electrolyte imbalances tied to declining kidney function
• Pharmacologic management across CKD stages
• Nutrition and lab-value interpretation relevant to adult kidney disease

Many candidates underestimate this domain because it feels "textbook" compared to the hands-on unit content in Domain 1. Don't. At 32%, missing this section can sink an otherwise strong score. Cross-reference how this domain interacts with the others in the complete domains guide.

AKI/DGF and Water for Dialysis: The Small but Costly 16%

Domains 3 and 4 combine for only 16% of the exam, but candidates frequently lose points here simply because they never studied the material at all - assuming low weight means low importance. It doesn't mean zero importance; it means efficient importance.

A realistic target: don't spend more than a fraction of your total study hours here relative to Domain 1, but don't skip it either - a handful of missed questions across two 8% domains adds up quickly against a 70%-correct passing standard.

Registration, Fees, and Eligibility Cheat Sheet

Getting the paperwork right is as important as knowing the content. Here's the compressed version:

• License: Full, unrestricted RN license (U.S. or territorial)
• Experience: 2,500 hours of nephrology RN experience with in-center hemodialysis patients, or educating/supervising such staff, within the prior 2 years
• Continuing education: 30 approved nephrology CE contact hours in the prior 2 years
• Standard fee: $350, or $300 for current ANNA, ASN, NKF, or NOVA partner members
• Processing fee: $50, nonrefundable, included in the above
• Retake fee: $200, or $175 for partner members, one-time

For a line-by-line cost comparison, including what partner membership actually saves you, see CDN Certification Cost 2026: Complete Pricing Breakdown. If you're unsure whether you currently meet the hours and CE thresholds, the CDN Requirements 2026 guide walks through qualification scenarios in detail.

Scoring Mechanics and What 95 Actually Means

The CDN exam doesn't score you on a simple raw percentage in the way many candidates assume. The passing mark is expressed as a standard score of 95, which currently corresponds to answering about 70% of scored items correctly. This standard is derived using an Angoff method, meaning subject matter experts rate the expected difficulty of each item, and the passing threshold is calibrated against that analysis rather than a flat curve.

Two practical implications:

• You won't know which ~25 of the 150 questions are unscored pilot items, so treat every question as if it counts.
• Because scoring is criterion-referenced rather than norm-referenced, your result reflects mastery against a fixed standard, not how you rank against other test-takers.

The 2025 pass rate of 65% across 356 administrations gives useful context for how this standard plays out in practice - read the full analysis in CDN Pass Rate 2026: What the Data Shows. For a plain-language explanation of the scoring formula itself, see CDN Passing Score 2026: Exactly What You Need to Pass.

Recertification Math for 2029

CDN certification is valid for 3 years. When your cycle ends, you have two paths:

1. Retake the exam under current fee and blueprint rules.
2. Renew by documentation, submitting proof of an unrestricted RN license, 1,500 nephrology RN hours, and 45 accredited nursing CE contact hours, including at least 15 nephrology-specific hours, accumulated during the cycle.

Note the difference between initial eligibility (2,500 hours, 30 CE hours) and renewal (1,500 hours, 45 total CE hours with 15 nephrology-specific). Mixing these numbers up is a common planning mistake - mark your renewal deadline now so you're not scrambling for hours in the final months of your 3-year cycle.

Final-Week Review Schedule

In the last stretch before your test date, allocate review time proportionally to domain weight rather than evenly across all four domains. A simple two-week compression looks like this:

This schedule assumes you've already built foundational knowledge over the preceding weeks - for the full multi-week plan, refer back to the CDN Study Guide 2026. Running full-length timed sets on CDN Exam Prep's practice tests in the final week helps calibrate pacing against the real 150-question, 3-hour format.

Frequently Asked Questions