"Nurse” vs. “Doctor”

I’ve been tinkering with a new research tool from Google labs – Ngram Viewer™ – which unravels cultural references inside the 15 million books scanned by the search engine giant. Looking at the proportion of published content that mentions the word “nurse” or “doctor” – over the period 1800 to 2008 – I found the Google application’s raw graphing data reveal some fascinating results. In a nutshell, the English language corpus has historically held doctors in higher esteem than nurses; around 1980, cultural references to nurses and to doctors nearly converged. And after 2000, doctors rose again in importance relative to nurses, and at a rapid clip. What explains the trend?