LONDON -- Switzerland has the highest rate of euthanasia in its widest sense, according to a survey of six European countries conducted by the University of Zurich in 2001 and 2002. The survey shows that end-of-life decisions were made in 51 percent of deaths analyzed.

The study, reported in the UK medical journal ******The Lancet******* this week, covers Belgium, Denmark, Italy, the Netherlands, Sweden and Switzerland. It's based on a random sampling of death register entries where end-of-life-decisions might have been made.

The most widespread intervention was the administration of drugs to alleviate distress with the knowledge that they would certainly or possibly hasten death. This type of intervention was the most consistent between countries with between 19 percent (Italy) and 26 percent (Denmark) of deaths following such treatment.

Doctors reported they had withheld treatment in between 4 percent (Italy) and 28 percent (Switzerland) of deaths, but withholding treatment may mean different things to different doctors, according to Karin Faisst, of the University of Zurich.

"One doctor may actively consider a treatment and reject it; but under the same conditions another doctor may reject the treatment without regarding it as having been a possibility -- it's a very subtle difference but it would result in different answers to the basic question," Faisst told Reuters Health.

Doctors reported giving drugs with the express intention of killing their patients in the Netherlands, Belgium and Switzerland -- 2.59, 0.30 and 0.27 percent, respectively -- with very few elsewhere. At the time of the survey, only Dutch doctors had any legal protection against criminal charges in those cases.

Only patients in Switzerland and the Netherlands were able to persuade their doctors to help them commit suicide: 0.36 percent and 0.21 percent, respectively.

"Nearly all of the suicides in Switzerland took place in the charitable organizations that help people to commit suicide," Faisst said.

The study draws attention to the lack of research on the subject -- outside the extensive studies in the U.S., comprehensive studies have only been conducted in the Netherlands, Belgium and Australia.

"It may be that this research will help to promote more of a dialogue involving doctors and the public. The doctors are often on their own, and some of them are even unhappy about discussing it," Faisst said.

Doctors were persuaded to take part in the current study by the promise of anonymity. All responses to the survey were returned to the Swiss Medical Association, which stripped the information of any personal details and connections before passing it on to the researchers.

"But we cannot exclude the possibility that non-response has to some extent affected our results, especially for Italy," Faisst said.

A follow-up survey will look more closely at the attitudes of doctors, sociological pressures and the ways in which doctors communicate with their patients. The current study points out that work elsewhere suggests that communication between the doctor and the dying is often less than ideal.