Clinical judgment and sometimes ethical judgment enter into these decisions where there are often no right or wrong answers and where there are no textbooks or RCTs that tell us what to do.
predecessor - something that precedes and indicates the approach of something or someone. harbinger, herald, forerunner, precursor. indicant, indication - something that serves to indicate or suggest; an indication of foul play; indications of strain; symptoms are the prime indicants of disease.
A successor may refer to: Someone who, or something which succeeds or comes after (see success and succession) Successor (horse), an American Thoroughbred racehorse; Successor was the working name for the class of British ballistic missile submarines, since renamed the Dreadnought-class