Great question, @lokesh
We have a definition of Conditions and Observations, as you cited in your question, but no clear guidelines to unambiguously decide whether a finding belongs to one or the other. It is a hot topic in the Vocabularies and people have strong opinions on the matter.
Over the years, we have had many debates. The most recent decisions are
- Disturb domains as little as possible (if something is assigned a domain, let it stick, we do not want many changes in domain between releases, so the phenotypes stay stable).
- Use SNOMED tags more often for domain assignment (previously we worked a lot on the hierarchies trying to find the most suitable ancestor to assign the right domain to all of the descendants - didn’t work out).
- If the clinical fact is important and you know that you will be looking for it, it makes a lot of sense to put it in a ‘cleaner’ Condition domain.
You may want to check this topic. I also invite you to come to the Vocabulary WG sessions in our Teams, where we can discuss cases you have.
According to current state, Hepatomegaly is a condition (tagged ‘Disorder’ in SNOMED, we followed the logic), as well as a Common bile duct stricture. Most conditions are diagnosed with procedures, so the fact of the procedure performed does not rule out a condition domain. Eg. you performed an ECG, found some ST-elevations and concluded that patient had a myocardial infarction. Keep it as AMI in a condition domain and you are fine.