Discussion

Our findings indicate that the development of the evidence base for nutrition research in Africa is focused on treatment or technical solutions to nutritional problems. In parallel, the capacity of African research institutions to publish research conducted in Africa is tied to that of their peers in the North. Over the investigated decade, a considerable proportion of publications were dedicated to nutrition in Africa. Intervention studies were a minority of the studies conducted. Similar estimates for nutrition research published in low- and middle-income countries in the second half of 2005 were obtained⁽ Reference Morris, Cogill and Uauy ^{16 )}. Most of the studies assessed therapeutic strategies. In addition, only a few studies tested interventions on how distal determinants of nutritional status can be modified to improve nutritional status. These ‘nutrition-sensitive’ interventions have a significant potential to create a context for the prevention of malnutrition⁽ Reference Ruel and Alderman ^{17 )}.

Clearly, a substantial amount of this research is driven by organisations situated outside Africa. This observation was shared by a review of nutrition research in West Africa⁽ Reference Aaron, Wilson and Brown ^{18 )} and in research output in 2005⁽ Reference Morris, Cogill and Uauy ^{16 )}. We acknowledge that this is in part attributable to training programmes outside Africa. Various African authors might have published their research in the context of training abroad. However, the network of authors’ affiliations of the papers indicates that root causes for this are to be found at a more structural level. Non-African academic institutions play a pivotal role in generating nutrition research in Africa. A significant amount of initiative and build-up of knowledge with regard to nutrition in Africa is concentrated in non-African institutions. In addition, cross-African linkages and networking of institutions within Africa seem secondary to networking with institutions based in the North. In line with a previous analysis⁽ Reference Hawkes, Turner and Waage ^{19 )}, our review shows how African research capacity in nutrition is tied to that of research institutions in the North. Clearly, international and intercontinental collaboration in research can leverage scientific knowledge and capacity in Africa and help generate answers to nutritional challenges. For such research collaboration to be considered a genuine partnership, it must rely on a balanced and complementary set of capacities⁽ Reference Rees ^{20 )}. International agreements now explicitly state how development efforts need to build equitable partnerships with recipient countries^{( 21 )}. Similar initiatives for research are yet to be established. In our opinion, the establishment of a code of conduct for academic collaboration would be a useful start.

Gillespie et al. previously argued that the current political commitment to nutrition needs to translate into the build-up of capacity at national and regional level⁽ Reference Gillespie, Haddad and Mannar ^{22 )}. Our findings suggest that the collaboration between African research groups might not be used to its full potential and call for a new approach that stimulates networking within the region and nutrition research output from Africa, owned by African institutions. Such an approach, however, will require genuine support from stakeholders in the North⁽ Reference Lachat, Nago and Roberfroid ^{23 )}. African researchers previously indicated that non-African research institutions and donors are instrumental in determining the research agenda of the continent⁽ Reference Van Royen, Lachat and Holdsworth ^{24 )}.

We acknowledge a number of limitations of the present study. Assessing research evidence through academic publications entails an inherent bias by limiting the assessment to output from peer-reviewed journals only. However, as discussed earlier⁽ Reference Mckee, Stuckler and Basu ^{4 )}, this approach remains a fairly objective way to assess research and the evidence base to date. Grey literature was not included in the review, as it is not centralised or indexed and mostly not peer-reviewed. Second, we retrieved research from MEDLINE and EMBASE, which index papers from most high-quality journals from Africa such as the South African Journal of Clinical Nutrition. Some journals that publish nutrition research from Africa (e.g. the African Journal of Food, Agriculture, Nutrition and Development) without an impact factor were hence not included in the review. Using both the MEDLINE and EMBASE databases, we are confident that we have captured the vast majority of high-impact journals in our review; that is, more than 90 % of the seventy-four journals in the subject category nutrition and dietetics in Web of Knowledge were included. We explored the type of studies and the authorship for a number of specific categories classified with a ‘major topic’ label in the databases. Studies that dealt with the topics but were labelled only with a usual MeSH or Emtree label for this subject were hence not included in this analysis. As a consequence, restricting the assessment to studies indexed under a major subheading implies that we have missed important studies. We are aware of studies that have tested preventive approaches for malnutrition in Africa⁽ Reference Adu-Afarwuah, Lartey and Brown ^{25 )}, using local resources⁽ Reference Mamiro, Kolsteren and Van Camp ^{26 )} or modifications of environmental factors such as agriculture⁽ Reference Faber, Phungula and Venter ^{27 )}. These studies did not appear in our assessment, as they were not indexed under the categories reviewed. In general, however, we have no reason to believe that the application of major topics is done differently from the assignment of MeSH terms for the different topics reviewed. Although we have worked on a sub-sample of manuscripts within the topics, biased results are unlikely in this regard. Our search terms did not capture research on iodine, Fe or Zn, as these are classified under inorganic chemicals in the MeSH tree. Similarly, we have no reason to assume that our findings would be different for other topics of nutrition that are studied in similar ways to the ones reviewed. Lastly, we focused our analysis on co-authorship with the first author. We did not analyse co-authorship of authors who were not affiliated with the first author, as this would populate the graphs with networks that might have played a secondary role in the research conducted. Although this appropriately focuses the analysis on the key institutions driving the publication of the findings, it reduces the importance of the last author of the paper, who is often the coordinating author.

The present review shows that the evidence base in nutrition research is generally limited and focused on treatment and technical solutions to nutritional problems in Africa. Solutions for nutritional problems that use existing resources and delivery platforms, developed from high-quality studies and responsive to African needs and context, are urgently needed to respond effectively to the nutritional challenges of the continent. Our analysis shows how the potential for cross-African collaboration to identify, implement and publish nutrition research from Africa remains grossly underutilised. Adequate investment in African-led nutrition research is needed to provide a sustainable response to the nutritional challenges of Africa. This will require equitable academic collaboration between high-income countries and African research institutions, with the balance of power placed with African researchers.