Sir, we read with interest the paper by C S Jones, R W Billington and G J Pearson (BDJ 2004, 197: 311–313) on the advantages and disadvantages of running clinical trials in general practices.

What is unclear from this paper is whether the practitioners were collaborators in this study or merely data collectors for academics. This paper, in our opinion, gives a very one sided view of practitioner involvement in a clinical trial. The authors make a number of suggestions as to the reasons why this particular clinical trial failed. In view of the title of the paper we would have expected the researchers to have reviewed and included the practitioners' experiences e.g. were they involved and happy with the design of the study, did they get comprehensive training and the necessary support during the trial and were they adequately funded?

It was clear from the review of the NHS National Programme in Primary Dental Care Research and Development Programme at the 'Reflection and Moving forward' Dental R & D Conference that general dental practitioners can lead and collaborate with academics in delivering successful research projects. Two recent publications have demonstrated how this can be achieved.1,2

There is no doubt that there is a paucity of evidence underpinning the science of dentistry. As 90% of patient care is provided in the primary care setting it is appropriate that this is where research should be undertaken rather than in academic settings.

A number of primary dental care research networks exist where primary care practitioners are involved in adding to the evidence necessary for improving patient care. We hope that those wishing to carry out clinical trials in general practice will not be discouraged by the conclusions drawn by the authors of this paper.

The authors of the paper respond: We thank Professor E Kay and Dr N Palmer for their interest in our paper. We wholeheartedly agree with their comments in their final paragraph that as the majority of patient care takes place in general practice this is the obvious place for such research to be undertaken. Indeed we did specifically state that the first of the references they cite 3 was similar to the improved procedure we suggested.

As we indicated in our reply to comments by Crisp and Burke, (BDJ 2005, 198: 282) the practitioners were involved from the outset with practice visits, training sessions and material to try before committing themselves to the project. We also discussed the funding with them at this stage. Throughout the running of the trial they were in contact with the organisers. All the clinical procedures they were asked to use were ones they routinely used in practice. The only slightly novel element was the test restorative material. This had been commercially available for about 5 years before the trial started and GDPs on the PREP panel placed 215 restorations without any reported difficulty.4 In addition, the two clinical authors (CSJ and GJP) had found the material easy to use in the restorative applications that were the subject of the trial, in general practice.

We agree with correspondents about the possibility of satisfactory collaboration between GDPs and academics and would again refer to Knibbs work with which two of us were involved.5,6,7 However, a controlled clinical trial is very different to clinical evaluations and audits which have both been very successful carried out by both Knibbs et al at Birmingham and by Burke's PREP panel and by others.