Editor—We hope that views on the effectiveness of a diagnostic technique are based on the results of well conducted randomised trials. We believe that our paper was useful in showing that a method found to be effective in improving specificity without decreasing sensitivity in an earlier and less rigorous trial was, in fact, not effective.1
Skin surface microscopy (dermatoscopy, dermoscopy) improves the accuracy of diagnosis of pigmented skin lesions when used by experts but not when used by inexperienced examiners.2,3 Only one randomised trial has been conducted with general practitioners; diagnoses from clinical photographs of 100 pigmented lesions were compared with those from dermoscopic photographs of the same lesions. When the general practitioners were trained, their diagnoses from the dermoscopic images were more accurate than those from the clinical photographs, but without training no difference in accuracy was observed.4
In the absence of trials that mimic actual general practice more closely we believe it is premature to conclude that dermoscopy in routine general practice will improve the diagnosis of pigmented skin lesions. Such a trial is in the planning stage in Australia.
Additional authors are R J Donovan, professor, Centre for Behavioural Research in Cancer Control, Curtin University of Technology, Perth, Australia, and G Emery, general practitioner, Perth, Australia.
Competing interests: None declared.
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