It seems that almost every medical institution from hospitals to pharmacies and clinics has been responsible for some kind of blunder in recent years. In the latest calamity, three patients have died and three are in intensive care because of an error involving a kidney dialysis machine. Until a full investigation has been conducted, the reasons for the tragedy remain unclear, but for the victims' families and future patients, the cause must be found quickly, and measures taken to see it never happens again. The question arises as to whether there is a common factor behind so many appalling errors. The list of cases, which includes patients who had milk pumped into their bodies or air into their veins, their nipples amputated, the wrong eye operated on, fallopian tubes severed, or were injected with a lethal substance, reads like the script of a horror film. Medical staff are fallible, like the rest of us, but unlike everyone else, their mistakes can have disastrous consequences. That is a heavy burden to carry, and at least the recent practice appears to be to admit blunders and, fortunately, cover-ups are a thing of the past. But unless efforts are made to prevent these incidents, the medical profession will gain a reputation for incompetence, and litigation could cripple the system. After the Hospital Authority held an inquiry last year it issued a 28-point plan to improve working methods in government hospitals. Doctors said then that without extra staff and resources it might be difficult to achieve all the improvements suggested. As errors have continued every month since, their fears appear to be justified. Another concern, that the authority is run by managers and executives more preoccupied with balance sheets than patient care, is not confined to Hong Kong. It is frequently levelled at hospital services overseas as administrators try to balance the soaring costs of hi-tech medicine against the pressure to stay within budget. But, by themselves, none of these factors explains the frequency of the blunders. Something more fundamental, more deep rooted, must lie at the source. Overwork may be part of the answer. But it is hard to escape the conclusion that basic training is inadequate, or that supervisory systems are lax. Some of these accidents have less to do with staff stress than sheer carelessness. When lives are lost, that cannot be excused.