The effect of advertising in clinical software on general practitioners’ prescribing behaviour

To the Editor: The observational study by Henderson and colleagues1 is important, as it is the first to look at the effect of advertising in clinical software on prescribing behaviour in Australia. However, the stated conclusion — that “exposure to advertisements in clinical software has little influence on the prescribing behaviour of [general practitioners]” — requires qualification, as there were potentially important confounders including the effects of other forms of pharmaceutical promotion that were not evaluated.