Segmental bowel-preparation quality at colonoscopy.
EndoscopicProcedure qualityValidated score
Clinical indication
Quality of bowel preparation at colonoscopy, scored 0-3 in each of three segments after cleansing manoeuvres. Used for procedure quality assurance and to decide the interval to the next examination.
What is scored
The calculator collects 3 items:
Right colon
Transverse colon
Left colon
Any item left blank stops the score being calculated — an incomplete form never reports as remission.
Interpretation
≤ 2 (repeat within 1 year)
Inadequate
3 - 5
Indeterminate
6 with every segment ≥ 2
Adequate, lowest acceptable
≥ 7 and every segment ≥ 2
Adequate
Bands as implemented in IBD Care. A band is a description of the score, not an instruction.
Limitations
Not IBD-specific and not a disease activity measure. It is scored after washing and suctioning, so it reflects the achievable view rather than the preparation the patient took. A total of 6 can conceal a segment scored 0, which is why segment scores should be read alongside the total.
References
Lai EJ, Calderwood AH, Doros G, Fix OK, Jacobson BC. The Boston bowel preparation scale: a valid and reliable instrument for colonoscopy-oriented research. Gastrointest Endosc 2009;69:620-5. PMID 19136102.
Calderwood AH, Schroy PC, Lieberman DA, Logan JR, Zurfluh M, Jacobson BC. Boston Bowel Preparation Scale scores provide a standardized definition of adequate for describing bowel cleanliness. Gastrointest Endosc 2014;80:269-76. PMID 24629422.
Content last reviewed 2026-10-10. References were resolved against PubMed, a service of the US National Library of Medicine, which does not endorse this site.
Use the calculator
Boston Bowel Preparation Scale is implemented as an interactive calculator in IBD Care, with its full guidance and scoring bands.