Michael White (politics, page 17, 27 April) suggests that our research on NHS Direct hasn't answered key questions like 'how many individual users there are as distinct from calls'.

Funnily enough, the answer can be found on page 13 of the same issue ('Blowing hot and cold', news focus):

excluding those very few callers who have used the service more than 50 times in a year, the 'average caller' to the first-wave sites uses the service 1.18 to 1.43 times per year. Thus, there are about 70-80 per cent fewer users than calls.

This data was included in our recent report of the evaluation, published in March 2000. It sometimes seems as if journalists (and opposition politicians) would prefer to complain about the lack of research than to study the findings already available.

James Munro Clinical senior lecturer Medical Care Research Unit Sheffield University