Table 1

Comparison of strengths and limitations of commonly used endoscopic scores

ScoreEndoscopic activity reportingResponsiveness to treatmentsPrognostic valueCentral reading
eMSPros
  • Gross classification of the gestalt of inflammation.

  • Present standard for Drug Agencies (FDA, EMA).

  • Development focused at responsiveness.

  • Extensively used over past 20 years in trials.

  • Limited data for a prognostic role in the literature.

  • Algorithms for central reading.

  • Categorical score leads to easier algorithms for adjudication.

  • Widely used over past 5 years.

Cons
  • Final score defined by worst lesion.

  • Lacks precision for global burden of severity and extent of lesions.

  • Lack of face validity

  • Endoscopic features only post hoc defined.

  • Limited spectrum at lower and higher spectrum of activity.

  • Lack of ability to highlight segmental healing.

  • Lack of responsiveness due to limited range.

  • Not developed with prognostic intent.

  • Limited interobserver agreement.

  • Inconsistencies between readers if insufficient washing of the mucosa.

  • Data on impact of reader paradigms on eMS-based endpoints is missing.

UCEISPros
  • Extensive characterisation and validation of elemental endoscopic lesions focused at agreement.

  • Better range than eMS.

  • Already used in some trials.

Cons
  • Lacks precision for global burden of severity and extent of lesions.

  • Lack of ability to highlight segmental healing.

  • Limited use in clinical trials.

  • Development not focused at responsiveness.

  • Not developed with prognostic intent.

  • Agreement and adjudication more complex for more granular scores as compared with categorical scores.

  • Modest agreement on some lesions (eg, bleeding).

RutgeertsPros
  • Clear-cut description of elemental lesions.

  • Development focused on prognosis.

  • Prognostic value has been reproduced.

  • Central reading easy to implement Algorithms for eMS easily exportable to Rutgeerts’ score.

Cons
  • Not an activity measure.

  • Does not evaluate endoscopic activity outside of the anastomotic site.

  • No responsiveness evaluation.

  • Developed for end-to-end anastomoses, never validated for side-to-side anastomoses.

  • Limited interobserver agreement.

  • Limited interobserver agreement.

  • No data on impact of read paradigm on outcome.

CDEISPros
  • Developed and validated in order to precisely report disease activity.

  • Shown in few trials, even if not explicitly developed for responsiveness.

  • Used in clinical trials.

  • Excellent inter-rater reliability.

Cons
  • Complexity.

  • Exact weight of each variable to be better clarified.

  • Unvalidated thresholds for remission and response.

  • The definition of remission does not exclude the presence of ulcers.

  • Not developed with focus on responsiveness.

  • Limited prognostic value of the sum score.

  • Agreement and adjudication more complex for continuous scores as compared with categorical scores.

  • Not developed for postoperative anatomy.

SES-CDPros
  • Developed and validated in order to precisely report disease activity.

  • Possibility to easily exclude a given variable.

  • Segmental and ulcer subscores can be calculated.

  • Shown in several trials, even if not explicitly developed for responsiveness.

  • Widely used in trials.

  • Excellent inter-rater variability.

  • Different reader algorithms available (fix or sliding scale for adjudication, paired reading …).

Cons
  • Relative complex.

  • Exact weight of each variable to be better clarified.

  • Unvalidated thresholds for remission and response.

  • Not developed with focus on responsiveness.

  • Limited prognostic value of sum score.

  • Agreement and adjudication more complex for more granular scores as compared with categorical scores.

  • No adjustment for missing segments due to sum score.

  • Not developed for postoperative anatomy.

  • CDEIS, Crohn’s Disease Endoscopic Index of Severity; EMA, European Medicines Agency; eMS, endoscopic Mayo Score; FDA, Food and Drug Administration; SES-CD, Simple Endoscopic Score for Crohn’s Disease; UCEIS, Ulcerative Colitis Endoscopic Index of Severity.