The effects of bonus payments on emergency service performance in Victoria

orectal specialists also had a higher case volume than the "other" surgeons, for whom a poorer patient outcome was noted. Cocks' comment that the bulk of general surgery consists of colorectal work cannot always be true the "other" surgeons are not mythical. He states that volume and experience are the key perhaps colorectal specialisation may ensure volume and experience. It was not suggested that rectal or colon cancer should suddenly be treated only by colorectal specialists. Clearly, some general surgeons have extensive experience in this field. In particular, if regional centres expect a high standard of care, then general surgeons with a variety of skills need to maintain their experience, with only selected cases requiring referral. Finally, it is impossible to comment on the Victorian study! when the methods and results are not published. With regard to Aitken's comments, all the studies comparing specialist or high volume surgeons with others were published in the past five years. Although his own publicationis interesting, neither the surgeon's experience nor patient outcome was analysed, and the article is not relevant here. I agree that there are a number of potential confounding factors in the publications analysed, as was stated. However, simply outlining these factors without specific examples, finding no contrary data, and then ruling the conclusions "weak" is difficult to sustain. Aitken states that four publications were omitted from the analysis. The first three of these did not make comparisons between individual surgeons or with other surgeons, and therefore could not be included in the review>" The fourths would have been included had it been identified; it was published three months after the final Medline search. It found that surgeons' case load had no statistically significant effect on two-year mortality." This may well be due to very incomplete data collection; for example, in 11% the Dukes stage was not known. The authors state: "We do not regard the level of findings from our hospital as conclusive, and they may reflect inadequate adjustment for unspecified case mix variables." An accompanying commentary notes ". . . with the comparatively small numbers in the various groups and high variability, it becomes statistically impossible to show that surgeons with small case-