Diagnostic Certainty Scale

Terminology to Convey Diagnostic Certainty in Radiology Report

Authors: Atul B. Shinagare, MD, Giles W. Boland, MD, Marcelo Di Carli, MD, William Mayo-Smith, MD, Stuart G. Silverman, MD, Aaron Sodickson, MD, PhD, Ramin Khorasani, MD, MPH.

Date: May 24, 2020

Diagnostic Certainty Scale

We recommend that the radiologists use the proposed diagnostic certainty scale to select the appropriate terminology to convey their SUBJECTIVE diagnostic certainty. The following macro will be inserted at the bottom of the report:

The Radiologist Diagnostic Certainty Scale is a guide that conveys to patients and providers a radiologist's subjective diagnostic confidence:

Most likely means very high probability
Likely means high probability
May represent means intermediate probability
Unlikely means low probability
Very unlikely means very low probability

You can find out more about our efforts to improve the clarity of radiology reports for our patients and providers by visiting https://rad.bwh.harvard.edu/actionable-radiology-reports.

Recommendations for radiologists

SUBJECTIVE diagnostic confidence Recommended terminology
Very high probability (>90%) ‘Most likely’
High probability (>75% and <90%) ‘Likely’
Intermediate probability (>25% and <75%) ‘May represent’
Low probability (<25% and >5%) ‘Unlikely’
Very low probability (<5%) ‘Very unlikely’
Other Recommendations
100% confident of diagnosis State the diagnosis or ‘diagnostic of’
Established or known diagnosis ‘Consistent with’ or ‘compatible with’
Avoid using these terms ‘probably’, ‘possibly’, ‘question of’, ‘suggestive of’, ‘suspicious of’, ‘may be’, ‘worrisome for’, ‘highly unlikely’


Our goal is to improve the clarity of radiologist’s contribution in devising the optimal care plan for each patient by creating an actionable report. In order to achieve this goal, it is important to clearly communicate the degree of diagnostic certainty in radiology reports.


Effective communication of diagnostic certainty is a key component of a high quality, actionable radiology report. Radiologists use various phrases (e.g., ‘consistent with’, ‘diagnostic of’, ‘likely’, ‘possibly’, ‘probably’) to convey diagnostic certainty; however, prior work has shown poor concordance between radiologists, referring physicians and patients regarding the use and meaning of these phrases (1-5). This can lead to ambiguity and frustration among radiologists and non-radiologists regarding the diagnostic certainty and subsequent patient management, and can negatively impact patients’ outcomes and experience of care. There has been a prior attempt to create a standardized lexicon using a limited number of diagnostic certainty phrases (6), however, demonstration of quantitative measures of improvement has been challenging.

A recent survey at Brigham Health and Dana Farber Cancer Institute to assess radiologists’ preferred terminology to convey diagnostic certainty highlighted the wide variation in perception of confidence associated with various phrases radiologists commonly use to convey diagnostic certainty (7). We have also analyzed radiologists' usage of diagnostic certainty phrases (8).

We used our data as well as input from the Radiology leadership, Actionable Reports Oversight Committee and clinical teams to create recommendations for radiologists on use of diagnostic certainty phrases. The Certainty Scale provides a common lexicon and guide that will accompany our radiology reports and will be accessible to our patients and providers and will be inserted at the bottom of the radiology reports containing diagnostic certainty phrases. We hope that this will reduce the unwarranted variability in communication of diagnostic certainty in our radiology reports.

Agreement Among Radiologists on Preference for Common Phrases to Covey Diagnostic Certainty

How to use this in your practice

To implement the Diagnostic Certainty Scale in your practice, add the "Diagnostic Certainty Scale" above as a macro in your dictation system or insert it the report template along with the provided link so that the radiologists, providers and patients can look up the rationale and details of the certainty scale.


  1. Khorasani R, Bates DW, Teeger S, Rothschild JM, Adams DF, Seltzer SE. Is terminology used effectively to convey diagnostic certainty in radiology reports? Acad Radiol. 2003 Jun;10(6):685–8.
  2. Gunn AJ, Tuttle MC, Flores EJ, Mangano MD, Bennett SE, Sahani DV, et al. Differing Interpretations of Report Terminology Between Primary Care Physicians and Radiologists. J Am Coll Radiol JACR. 2016 Dec;13(12 Pt A):1525-1529.e1.
  3. Mityul MI, Gilcrease-Garcia B, Searleman A, Demertzis JL, Gunn AJ. Interpretive Differences Between Patients and Radiologists Regarding the Diagnostic Confidence Associated With Commonly Used Phrases in the Radiology Report. AJR Am J Roentgenol. 2017 Oct 12;1–4.
  4. Rosenkrantz AB, Kiritsy M, Kim S. How “consistent” is “consistent”? A clinician-based assessment of the reliability of expressions used by radiologists to communicate diagnostic confidence. Clin Radiol. 2014 Jul;69(7):745–9.
  5. Hobby JL, Tom BD, Todd C, Bearcroft PW, Dixon AK. Communication of doubt and certainty in radiological reports. Br J Radiol. 2000 Sep;73(873):999–1001.
  6. Panicek DM, Hricak H. How Sure Are You, Doctor? A Standardized Lexicon to Describe the Radiologist’s Level of Certainty. Am J Roentgenol. 2016 Jul;207(1):2–3.
  7. Shinagare AB, Lacson R, Boland GW, Wang A, Silverman SG, Mayo-Smith WW, Khorasani R. Radiologist preferences, agreement and variability in phrases used to convey diagnostic certainty in radiology reports. Journal of American College of Radiology, In Press.
  8. Lacson R, Odigie E, Wang A, Kapoor N, Shinagare A, Boland G, Khorasani R. Multivariate analysis of radiologists' usage of phrases that convey diagnostic certainty. Acad Radiol, In Press.