Select the descriptor that best matches the visual appearance of the colon at the time of insertion.
Guidelines & Evidence
Clinical Details
Section 1
When to Use
When to Use
Global assessment of colonoscopy bowel preparation quality
To standardize endoscopy reports in clinical research (prep comparisons)
To assist in determining the screening/surveillance interval
Used as a holistic "as encountered" rating before significant cleaning maneuvers
Rating Logic
Unlike segment-specific scales (e.g., Boston), Aronchick is a qualitative global rating. It captures the overall cleanliness encountered during the procedure, reflecting both the patient's adherence to prep and the efficacy of the agent.
Section 2
Formula & Logic
Qualitative Categories
01
Excellent: Small amount of clear liquid (< 5% of surface) requiring no suctioning.
02
Good: Small amount of liquid or feces that is easily suctioned; > 90% of mucosa visible.
03
Fair: Semi-solid stool that suctions away; > 90% of mucosa ultimately visible but requires extra time for cleaning.
04
Poor: Large amounts of semi-solid/solid debris that cannot be cleared; < 90% of mucosa visible.
05
Inadequate: Solid stool that prevents completion of the procedure; mandates aborting and repeating.
Surveillance Interpretation (USMSTF)
01
Excellent/Good: Standard screening/surveillance intervals apply.
02
Fair: Interval determined by the endoscopist (typically shortened if polyps > 5mm could be missed).
03
Poor/Inadequate: Repeat colonoscopy within 1 year (or sooner if diagnostic clinical suspicion is high).
Section 3
Pearls/Pitfalls
Aronchick vs. BBPS (Boston Scale)
The Boston Bowel Preparation Scale (BBPS) is currently preferred for routine clinical practice because it is segmental and scored AFTER cleaning. Aronchick remains valuable in research specifically because it assesses the "raw" encounter, making it a better test of the preparation agent itself vs. the endoscopist's cleaning persistence.
Missed Lesion Correlation
"Fair" preparations are notorious for missing flat lesions (Sessile Serrated Lesions) in the right colon. If the right colon was not perfectly visualized despite cleaning, the endoscopist should document the procedure as inadequate for right-sided surveillance.
Key Success Factors
Split-dose prep (morning of) is the single biggest predictor of an "Excellent" rating
Low-fiber diet 2-3 days prior improves "Encencountered" cleanliness
In patients with chronic constipation, a 2-day prep protocol is often required for a "Good" rating
Section 4
Next Steps
Clinical Action
01
Inadequate Encounter: Schedule repeat with more aggressive prep (e.g., 4L PEG split-dose).
02
Fair Encounter: Document the uncertainty of detecting polyps < 5mm. Consider 3-5 year follow-up instead of 10.
Complementary Tools
Boston Bowel Prep Scale (BBPS)
Ottawa Bowel Preparation Scale (OBPS)
Adenoma Detection Rate (ADR) Benchmark
Section 5
Evidence Appraisal
Guideline Recommendation
Preparation of the colon for colonoscopy.
Kastenberg D et al. • Gastrointestinal Endoscopy. 2002;56(5):713-20. Review of quality scales including Aronchick.
Developed by Dr. Craig Aronchick and colleagues in the late 1990s at Pennsylvania Hospital. It was instrumental in early trials for new bowel prep agents, providing a standardized way to quantify what is often a highly subjective "feeling" of colon cleanliness.
