Twenty-five physicians were charged at Nuremberg after World War II for Nazi inhuman experimentation on humans. Seven were acquitted, 9 were imprisoned, and 9 were sentenced to death. The Nuremberg code was laid down in 1946 in response to the criminal Nazi experiments on humans during the war. The main provisions of the code were: (a) Voluntary informed consent (b) No random or unnecessary experiments (c) Animal experiments and survey of disease natural history before subjecting humans to similar experiments (d) Avoiding unnecessary physical and mental suffering (e) The researchers must be scientifically qualified (f) subjects can withdraw at any time (g) the investigation is stopped if the patient is in danger. There was however no mention of experiments involving children.

HELSINKI DECLARATION

The World Medical Association drew up the Helsinki Declaration, incorporating the Nuremberg code, in 1964. The latest version (1996) was approved by The 48^th Assembly of the World Medical Association held in South Africa in 1996 approved the latest version. The code is divided into three sections: Introduction, Basic principles, clinical research, and non-clinical research.

The introduction asserted that the primary duty of the physician was to act in the best interests of the patient. It pointed out the role of research in advancing knowledge of diagnosis, therapy, or prophylaxis with the caution that such research always carries a risk to the subject. A distinction was made between clinical research involving search for new treatment and diagnostic modalities and purely scientific research that had no direct benefit to the patient. This distinction is however questionable because clinical research in based on prior basic scientific research. The code also alluded to environmental concerns and the welfare of animals used in research.

The following basic principles were included in the code. Research on human subjects must conform to generally accepted scientific principles and must be preceded by laboratory and animal experiments. A competent and independent committee must approve the research protocol, setting out all details of the research and a statement of adherence to the Helsinki declaration. The research is carried out by qualified researchers and under the supervision of a medically qualified person who must assume full responsibility for the welfare of the research subjects. The research must be preceded by careful risk-benefit assessment. The research can be carried out only if its risks are predictable, the objectives are important when considered with the potential risks, and the benefits outweigh the risks. Research subject integrity in the form of privacy, physical, and mental welfare must be respected. Research subjects are entitled to full disclosure that covers the aims, methods, and potential hazards of the research before they give their voluntary informed consent. They should be informed that they are free to abstain from the study or to withdraw at any stage. Proxy consent is obtained for the legally incompetent, children or the mentally retarded. Results of the research will be accepted for publication only if they are accurate and conform to the principles of the Helsinki Declaration.

The declaration defined and approved clinical research as medical research combined with medical care. The physician is free to use a new therapeutic or diagnostic measure that in their judgment has hope of improving life and alleviating suffering. The potential benefits, hazards, and discomfort of the new method must be weighed against the best current and available diagnostic and therapeutic methods. Use of a placebo in a control group is allowed if no better method is available.

The declaration defined non-clinical biomedical research as non-therapeutic research involving humans carried out only on volunteers either healthy volunteers or patient volunteers. In case of patient volunteers the experimental design should not be related to their illness. The lead physician in the research team retains responsibility for subject welfare. The research is terminated as soon as is judged harmful to the research subjects. In any case the interests of science and society should never take precedence over the welfare of the research subjects.