Digital-Only Scope & CAT Scoring
Key Takeaways
- RHS has tested digital radiography only since July 7, 2022—film processing and darkroom steps are out of scope
- Study PSP, CCD/CMOS sensors, digital density/contrast/sharpness, and sensor/PSP care—not developer, fixer, or safelights
- DANB administers RHS with computer adaptive testing (CAT); scoring reflects difficulty of items answered correctly, not a simple percent correct
- Each candidate still sees the same percentage of questions from each domain (50/25/25 mix)
- The average candidate answers around 50% of CAT items correctly—and can still pass if those items are at the right difficulty for a scaled 400
- Stop chasing a raw 70% target; aim for consistent mastery of blueprint tasks and a scaled score of 400+
Digital-Only Scope & CAT Scoring
Quick Answer: Since July 7, 2022, DANB RHS tests digital radiography only—no conventional film or darkroom content. The exam uses computer adaptive testing (CAT). Scores reflect the difficulty of questions you answer correctly; the average candidate gets about 50% of items right and can still pass. You need a scaled score of 400 (100–900 scale), not a fixed percent-correct cut score.
Two design choices shape how you should study RHS in 2026: the digital-only content boundary and CAT scoring. Misunderstanding either one wastes hours—either on obsolete film trivia or on a false “I need 70% raw” target that does not match how DANB reports results.
Digital-only since July 7, 2022
DANB’s outline states plainly: the RHS exam tests digital radiography only, and no conventional, film-based concepts have been tested since July 7, 2022. That date is a hard content cutoff, not a soft preference.
Out of scope (do not prioritize):
- Manual film processing chemistry (developer, fixer, replenishment rates)
- Darkroom safelight wattage/distance and fog tests as exam staples
- Film packet composition and emulsion layers as primary content
- Automatic processor roller maintenance framed as film-era tasks
In scope (build fluency here):
- Intraoral receptors: phosphor storage plates (PSP) and solid-state sensors (CCD, CMOS)
- Receptor placement with holders, bite blocks, and bitewing tabs
- Digital image qualities: density, contrast, sharpness, and how mA, kVp, and time affect the file you capture
- Underexposure vs overexposure appearance on digital images (noise/light vs dark/washed detail)
- Sensor integrity, PSP handling/scratches, barrier use, and erasure/scan workflow concepts
- Error patterns that still exist digitally: overlap, elongation, foreshortening, cone cut, motion blur, jewelry artifacts
How CAT works on RHS
DANB administers exams with computer adaptive testing (CAT). In CAT, the testing engine selects subsequent items based on your running performance. Exams are scored based on the difficulty of the questions answered correctly, which lets DANB pinpoint ability more precisely than a fixed form where every candidate sees the identical item set.
Critical CAT facts from the RHS outline:
- Domain balance is preserved. Each candidate is presented with the same percentage of questions from each domain. You still face the 50/25/25 mix—CAT does not let you “dodge” infection control by answering technique items well.
- Average correct rate ≈ 50%. DANB states the average candidate will answer around 50% of the questions correctly. That is expected under adaptive difficulty, not a sign that the exam is “impossible.”
- Pass line is a scaled 400. Results are reported as a scaled score from 100 to 900. A minimum passing scaled score of 400 is required. The scaled score is neither a number-correct nor a percent-correct score. Performance is criterion-referenced against the standard, not curved against other test-takers that day.
Why “~50% correct can still pass” is not a loophole
Students sometimes hear “50% correct” and relax. That is the wrong lesson. CAT raises item difficulty as you succeed. A strong candidate may miss harder items and still demonstrate ability above the cut; a weak candidate may get many easy items wrong and fall below 400 even with a similar raw hit rate. Your job is not to game a 50% raw target—it is to know Domain I–III tasks well enough that the adaptive engine keeps you in the ability band that maps to 400+.
Practical study implications:
- Do not stop a practice set early because you are “above 70%.” Mix easy landmark ID with harder error-correction and ALARA judgment items.
- Review every miss by domain weight. A technique miss costs more in blueprint terms than an equal number of low-weight trivia misses.
- Train switching. CAT and mixed forms jump topics; drill short blocks that rotate technique → protection → infection control.
- Ignore letter-grade thinking. Think “scaled 400 competence,” not “I need a B on a classroom quiz.”
- Simulate unfinished items. With ~48 seconds per question, practice committing to an answer and moving on—CAT does not reward long debates on a single stem.
Delivery choices do not change the content rules
RHS is offered in person and by remote online proctoring. You choose the method. Remote proctoring uses your computer with webcam/microphone monitoring. Neither delivery mode reintroduces film content or switches off CAT. The digital-only rule and the scaled 400 standard apply either way. Pick the environment where you can sustain focus for a full hour; technical setup stress on remote day is not an excuse the outline will soften for you.
Study checklist for this section
Which statement correctly describes DANB RHS content and scoring?