Headcount is generally not a good metric to measure productivity or effectiveness as it's a number that politicians love to manipulate to for their respective ideologies (social welfare expansion for the left and budget restriction for the right).
Figures I found for 1997 and 2007 are similar, showing proportions of clinical staff at 49% and 51% respectively. http://content.digital.nhs.uk/catalogue/PUB00829/nhs-staf-19...
And medical school intake has risen from 3,749 in 1997/98 to 6,262 in 2012/13 - a rise of 67.0 per cent. http://www.nhsconfed.org/resources/key-statistics-on-the-nhs
It's still not enough - Britain spends maybe 2% GDP less on healthcare than other rich European countries. But at the end of Labour's time in power, there were 1/3rd more doctors and nurses employed by the NHS. The funding increase helped enormously.
Edit. But yes, the massive IT projects in the NHS were a hugely wasteful like all massive government IT projects. The approach of the Government Digital Service seems to be a huge improvement.
The public sector employment figures on page 13 of this report are pretty telling: https://www.ifs.org.uk/bns/bn145.pdf
1991-1997: NHS headcount static at 1.2M under Tories
1997-2010: NHS headcount grows to 1.6M under Labour
2010-2013: NHS headcount begins falling under Tories