The objective was to develop evidence -based recommendations and a research and educational agenda for the non-pharmacological management of hip and knee osteoarthritis (OA). The multidisciplinary task force comprised 21 experts: nurses, occupational therapists, physiotherapists, rheumatologists, orthopaedic surgeons, general practitioner, psychologist, dietician, clinical epidemiologist and patient representatives. After a preliminary literature review, a first task force meeting and five Delphi rounds, provisional recommendations were formulated in order to perform a systematic review.

The perspective of `children as social actors' has created a field with new ethical dilemmas and responsibilities for researchers within the social study of childhood. These concern, for example, the greater potential for conflicts of interest, often hitherto unrecognized, between children and other actors. It is suggested to work from a perspective of `ethical symmetry' in research relationships with children while taking into account the social and cultural positioning of children in their particular circumstances. An illustrative example is given of the ethical issues that can arise when children are seen as social actors. It is argued that codes of ethics, reflexivity and collective professional responsibility are all required in order to meet the ethical demands that flow from these newer perspectives on children. It is proposed, therefore, that researchers develop a set of strategic values within which individual researchers can anchor the tactics required in their everyday practice in order to work reflexively. Finally, it is suggested that, in order to develop ethical practice for the future, dialogue is required on two levels: between researchers as a means of collectively sharing experience; and between researchers and children as participants in the ongoing research process.

The recognition of children's social agency and active participation in research has significantly changed children's position within the human and social sciences and led to a weakening of taken-forgranted assumptions found in more conventional approaches to child research. In order to hear the voices of children in the representation of their own lives it is important to employ research practices such as reflexivity and dialogue. These enable researchers to enter into children's 'cultures of communication'. Drawing on detailed examples from an ethnographic study on child health and self-care, the article examines issues of power, voice and representation central to