Diagnosis

Diagnosis Topic

Note: this is a cross cutting concern which impacts many HL7 groups, and needs to be reviewed and vetted by SDWG, PCWG, ECWG, CIC and TermInfo.

Process

• Final Objective
  • Balloted specification(s) may be considered
    • What Realm?
    • DSTU v. Normative v. Informative?
• How to Get there
  • Participate in discussions during conference calls
    • Document input on this wiki
  • Working directly on wiki
    • Discussion v. wiki page: please confine discussion to discussion page. This page should be considered the "in progress draft" of something we can send to ballot.
    • Terminology / vocabulary.
      • Help track down all the relevant codes which identity a "type" of diagnosis (not the diagnosis itself) would be very helpful.
      • We need to define a value set we can safely use without ambiguity across domains and use cases
• Model of meaning v. model of use
  • This is where a lot of the complexity is. We need to define the different use cases, as well as how to define models which work for them such that they have a singular model of meaning

Diagnosis Definition is Contextual

The term diagnosis, derived from the Greek term διάγνωσις (discernment), has context dependent meanings. As such, use will require formal definitions so it can be properly treated algorithmically. It is often defined as the art or act of identifying a disease from its signs and symptoms as well as the conclusion reached. (Merriam Webster). Often diagnosis is further divided based upon source of knowledge, e.g. in cancer there is a concept of the “tissue diagnosis” (the type of cancer as identified from an examination of biopsy material).

There is also a distinction made by some between the “clinical diagnosis”, i.e. the diagnosis which is determined by history and physical exam, “radiologic diagnosis” (e.g. the discovery of pathognomonic features in a diagnostic imaging procedure, “medical diagnosis” (the diagnosis by a physician) and nursing diagnosis (the concept of diagnosis used by nurses).

Medical Diagnosis

The medical diagnosis attributes a causative pathologic or physiologic process to a given set of clinical findings. Medical diagnosis typically involves multiple modes of investigation. It usually is predicated upon a history of the presenting problem, a review of systems (symptoms specific for different organ systems), a physical examination

Differential Diagnosis (q.v. LOINC 56865-9)

A differential diagnosis is a set of

Salient Features

Certainty and Uncertainty

All diagnosis are associated with a non-zero probability of being wrong. While many diagnosis approximate zero, there are always possibilities of laboratory error, mix-up of specimens, errors on the part of any of the healthcare team (particularly radiologists and pathologists, upon whom great importance is placed for accuracy). This is typically most evident with clinical diagnosis.

Associations between diagnosis and other key elements of an EHR, health history summary, PHR, or other HIT.

Changes in Diagnosis

Often a patient’s diagnosis changes. This can be due to diagnostic error, error in recording or codeing the diagnosis, error introduced by use of ICD codes from billing systems, further information becoming available which further defines or corrects a diagnosis, and progression of disease.