VE appears to add extra parameters to infoboxes that a user has not requested / added. Here is an example https://en.wikipedia.org/w/index.php?title=Hiatal_hernia&type=revision&diff=828702902&oldid=828702735&diffmode=source
Okay so using VE I added the term "testing" in this edit https://en.wikipedia.org/w/index.php?title=Hiatal_hernia&type=revision&diff=828884102&oldid=828724269&diffmode=source
The VE tool than went ahead and added "synonym" duplicating the "synonyms" parameter" and "speciality" duplicating the "field" parameter. Either synonym or synonyms is accepted as the same in this infobox. Same with field and speciality.
I did not mean to add these empty parameters. Unless someone adds text into one of them they should I hope not be added. Is it possible to tern of "recommended" for fields in the "infobox medical condition (new)"
Okay WAID has told me how to fix the issue https://en.wikipedia.org/wiki/Wikipedia_talk:WikiProject_Medicine#VE_adding_extra_parameters
Have made the change here so IMO nothing more needs to be done https://en.wikipedia.org/w/index.php?title=Template:Infobox_medical_condition_(new)/doc&type=revision&diff=828895544&oldid=822056227&diffmode=source
When adding templates in the visual editor, blank parameters are added when they are marked as "suggested" in that template's data. This is intended functionality. If users don't want those parameters added, they should not be marked as suggested in the template data. Doc James has now done that for this specific template.