inability to give an informed consent and also to their need for further protection and sensitivity from the researcher as they are in a greater risk of being deceived, threatened or forced to participate. Many are in favour of the use of such subjects in research whilst others would argue strongly against it. Most condition their responses according to the seriousness of the research, the level of potential risk and the availability of alternatives.6 According to Burns and Grove vulnerability increases the need for justification for the use of such subjects.5 An intense analysis of potential risks and benefits should be the first step of starting such a research and careful approach should exist both in acquiring consent and during the research procedure itself. Persons with diminished autonomy are also more vulnerable to invasion of privacy, since their right to privacy is limited in contrast to other's right to know. In the case of mentally ill, family as well as employers and colleagues have the right to know while patients may not be able to see the testimony of others in their own record. In the case of mentally ill patients, it is important to measure comprehension and develop valid tools for it, before obtaining informed consent to participate in a research study. In a descriptive study of Beebe and Smith the Evaluation to Sign Consent (ESC) form was used in order to document comprehension in 29 schizophrenia outpatients.24 Participants living in supervised housing were significantly more likely to require prompts than those living alone. Participants prescribed two antipsychotic medications were significantly more likely to require a prompt than those prescribed only one antipsychotic. According to Lasagna there are strong feelings among professionals who disagree with experimentation on vulnerable groups.25 However, the potential improvement of their nursing care raises the issue of careful consideration before rejecting or accepting this kind of research. Skills of the researcher Jameton declares that in research the three more important elements are the competency of the researcher, the careful design, and worthwhile expected outcomes.13 The Royal College of Nurses HEALTH SCIENCE JOURNAL ® VOLUME 5, ISSUE 1 (2011) What are the Major Ethical Issues in Conducting Research? Is there a Conflict between the Research Ethics and the Nature of Nursing? pp: 3-14 E-ISSN:1791-809X www.hsj.gr Health Science Journal® All Rights Reserved 8 declares that nurse researchers should have the necessary skills and knowledge for the specific investigation to be carried out and be aware of the limits of personal competence in research. Any lack of knowledge in the area under research must be clearly stated. Inexperienced researchers should work under qualified supervision which has to be reviewed by an ethics committee.26 What is more, careful choice of method for data collection, to ensure validity and reliability, are two main requirements that must be met in all kinds of research. The choice depends on the object of the study. When human beings are involved, all the ethical issues, discussed above, must be taken into account.2 The nature of Nursing The nature and essence of nursing reflects on human beings and their relationship with health.27 Mckenna states that the primary scope of nursing is to help persons to adapt in different stages of illness which is a rather task-orientated and behaviouralistic approach.28 On the other hand, Swanson notes that nursing views persons as a whole and health as a subjective and meaningful experience of integrating with the environment.29 Mckenna views nursing's main elements as interpersonal interactions which involve practical actions but Chinn and Jacobs make hints on holism as well.28,30 Literature contains diversed nursing definitions which indicates the complicate and uncertain nature of it.28 However, most authors reflect on caring as the most important part of nursing. Raya focuses on the unique element of caring in nursing while Swanson views Nursing in the same scope as "informed caring for the wellbeing of others".29,31 The ANA policy statement declares that "Nurses diagnose and treat human responses to actual or potential health problems".8 This is quite indicative of