Diagnostic certainty

Diagnostic certainty is a component of all cases and reflects how well the diagnosis has been established. 

Where is it located

The user interface to set Diagnostic certainty (DC) is visible immediately below the title in case edit mode. It comprises a slider, with descriptions of each state. 

There are 5 possible levels of diagnostic certainty 

1. Possible
   • the preferred diagnosis is one of a number of possible diagnoses, and although it is perhaps more likely, other conditions remain viable alternatives.
   • cases like this are sometimes worthwhile, but often they are not.
   • what you need to do: include a discussion on why you favour your diagnosis.
   • be prepared for your case to be rejected for publication; that's ok, you can always keep it as one of your unlisted cases.
2. Probable
   • the preferred diagnosis is far more likely (>90%) than any alternative, but the diagnosis has not been established.
3. Confirmed but unsubstantiatedAlmost certain
   • you have reasongood reasons to believe the diagnosis was confirmed, but you do not have direct access to the proof and cannot upload it.
   • for example, examples:
     • you collected this case some time ago and have included "path proven" in the description but nonot the actual histology report.
     • alternatively the referrala secondary source states the diagnosis which was established elsewhere.(e.g. the referral, or the treating unit or a colleague tells you the result of a biopsy) but you haven't seen the report yourself 
   • Confirmed and substantiatedimaging is almost pathognomonic but it is conceivable that an unusual appearing other entity could have similar appearances
   • examples:
     • adrenal myelolipoma has very characteristic appearance but it is conceivable that an unusual appearing retroperitoneal liposarcoma could appear similar 
4. Certain
   • the diagnosis is known beyond100% certain based on:
     • unequivocal or pathognomonic imaging appearance
     • clinical, surgical or pathological proof directly obtained from a doubt and proof is included in this case.
     • for example, histology report +/- slides are included, or confirmatory tests have been provided and those results included.
     • sometimes images are pathognomonicprimary source by the uploader (e.g. fracturesdirectly from the histology report).
   • were appropriate you should include substantiating evidence (e.g. histology report/slides, diagnostic laboratory test/values) 
   • Not sure? Ask yourself this: "Would a journal accept the diagnosis if you submitted it as a case report?" In other words, would a cynical and needskeptical third party agree that there was no supportive evidencedoubt about the diagnosis? If your honest answer is "yes" then the diagnosis is considered "Certain".
5. Not applicable
   • the images are not of a patient with a particular diagnosis.
   • for example, they may be a examples:
     • normal scan for teaching purposes
     • diagrams, or alternatively a diagram orillustrations, or flow chart.

How diagnostic certainty is used on the site

The diagnostic certainty of a case has many implications and functions. 

Firstly it has a strong influence on case completeness, and therefore when sorting search results by case completeness cases with high DC will be favoured. Similarly, these cases will be more frequently shown in Quiz Mode. 

Secondly, search results will show the DC level as a coloured dot (matching the slider). 

Thirdly, search results can be (soon) filtered to only show cases of a minimum DC (e.g. at least confirmed but unsubstantiated).