Salway et al. BMC Public Health 2011, 11:514 http://www.biomedcentral.com/1471-2458/11/514 the phenomenon under investigation, the multi-dimen- sional approach views different data collection methods as offering alternative perspectives on the social phe- nomenon of interest. Taking this approach, the com- plexity, uncertainty and potential contradictions of our cross-national comparative data can be seen positively, offering the possibility of asking distinctive but inter- related questions about migrant/minority maternity experiences. The aim of such an approach would not be integration of the data into one coherent whole, but rather an understanding of the migrant/minority experi- ence as multidimensional. Similarly, Wrede et al.’s [16] notion of ‘decentred comparative research’, in which there is a conscious effort to ensure both reflexivity and local sensitivity in analysis is helpful. As discussed above, research into migration, ethnicity and health, we believe, demands an in-depth understanding of the socio-cultural, economic and political context. Both these orientations to data analysis and integration view the complexity and ‘messiness’ of the data generated through such a holistic approach as beneficial rather than problematic. Nevertheless, a whole host of practical and procedural issues arise in terms of how an international team should actually work with the datasets generated to con- duct analyses and generate findings. Furthermore, this type of integration is challenging both for the research- ers who may struggle to extract meaning from large volumes of ‘untamed’ data and for research users for whom the nuance, complexity and uncertainty of result- ing research products may be difficult to incorporate into decision-making. Incorporating a critically reflexive approach to research practice A final methodological issue worth noting related to the degree of critical commentary on ethical and scientific rigour in researching ethnicity that was evident across the settings. Thus, while the UK researchers were actively involved in debates regarding whether and how health researchers should engage in research related to minority ethnic populations and the potential for such work to do more harm than good [63,64], this was not so evident for the other country teams. Interestingly in Canada, while there is a well-developed body of litera- ture relating to the ethics of researching with indigenous populations [65], this has yet to be expanded to address migrant/minority groups in any detail. In Germany, too, this area is relatively under-explored. As such, this was an area where it was felt the UK research tradition could usefully enhance the work of the Canadian and German research teams. At the same time, however, we were alerted to the dangers of imposing Anglocentric thinking in other contexts, a tendency that has been Page 9 of 13 highlighted by other commentators on comparative research [15,22] and, as noted above, identified several areas of learning for British researchers. 3. Establishing an effective operational structure In common with many complex international projects involving several partners, a number of differences across the three countries presented operational chal- lenges to effective working. Livingstone [20] has high- lighted some of the personal and organisational challenges of cross-national working and Wrede et al. [16] offers useful insights into teams making the most of international collaborative work; we do not reiterate these themes here. However, two issues are worth dis- cussing because of their relation to racialised hierarchies within academia and the generation of knowledge about migrant/minority people: (i) the composition of research teams; and (ii) the involvement of members of the pub- lic and service users in research. Composition of research teams Though notions of ‘insider’ and ‘outsider’ are complex [66], the social identity of the researcher is a fundamen- tal element in the generation of knowledge about migrant/minority people [67,68]. Furthermore, the extent to which people of migrant/minority background gain opportunities to become researchers is an ethical and political issue. Indeed, recent principles for social research highlight the need to support the careers of minority researchers [69]. Given these concerns, it was important to consider the differential make-up of the research teams and the extent to which there was a pool of potential researchers from diverse migrant/minority backgrounds available in the three countries. In this respect, the UK and Canada appeared to be at an advan- tage compared to Germany. Thus, while both the UK and Canadian teams included several researchers of migrant/minority identity who were multilingual, this was less so for Germany. That said, researchers from all three countries were conscious of the persistent need to enhance opportunities for minority researchers in their own academic environments, though progress seemed more likely to be achieved in Canada - with its stronger emphasis on the development of neophyte researchers - than in the UK or Germany. Service user involvement and participatory research The involvement of service users and members of the public in health research is a well-established element of research design in the UK. While not without critics (and consisting of a variety of approaches in practice), researchers are expected to adopt strategies that facili- tate the involvement of users within the research pro- cess and these are commonly subject to scrutiny within