Trust me I'm a doctor - Origin of the phrase

Searching for the origin of the phrase, "Trust me I’m a doctor", which I take as a humorous way of simply saying, "Trust me!", it seems mostly to be attributed to the title of a British TV show of that name from 1996.

The original series of the show ran for four series between 1996 and
1999.

https://en.wikipedia.org/wiki/Trust_Me,_I%27m_a_Doctor_(TV_series)

However I have a strong feeling that the name of the TV show came from the expression rather than vice-versa.

Does anyone here have any proof (or anecdotal evidence) that predates 1996?