title: Geographic information analysis and web-based geoportals to explore malnutrition in Sub-Saharan Africa: a systematic review of approaches.
abstract: BACKGROUND
  Childhood malnutrition is a serious challenge in Sub-Saharan Africa (SSA) and a major underlying cause of death. It is the result of a dynamic and complex interaction between political, social, economic, environmental and other factors. As spatially oriented research has been established in health sciences in recent years, developments in Geographic Information Science (GIScience) provide beneficial tools to get an improved understanding of malnutrition.
  
  
  METHODS
  In order to assess the current state of knowledge regarding the use of geoinformation analyses for exploring malnutrition in SSA, a systematic literature review of peer-reviewed literature is conducted using Scopus, ISI Web of Science and PubMed. As a supplement to the review, we carry on to investigate the establishment of web-based geoportals for providing freely accessible malnutrition geodata to a broad community. Based on these findings, we identify current limitations and discuss how new developments in GIScience might help to overcome impending barriers.
  
  
  RESULTS
  563 articles are identified from the searches, from which a total of nine articles and eight geoportals meet inclusion criteria. The review suggests that the spatial dimension of malnutrition is analyzed most often at the regional and national level using geostatistical analysis methods. Therefore, heterogeneous geographic information at different spatial scales and from multiple sources is combined by applying geoinformation analysis methods such as spatial interpolation, aggregation and downscaling techniques. Geocoded malnutrition data from the Demographic and Health Survey Program are the most common information source to quantify the prevalence of malnutrition on a local scale and are frequently combined with regional data on climate, population, agriculture and/or infrastructure. Only aggregated geoinformation about malnutrition prevalence is freely accessible, mostly displayed via web map visualizations or downloadable map images. The lack of detailed geographic data at household and local level is a major limitation for an in-depth assessment of malnutrition and links to potential impact factors.
  
  
  CONCLUSIONS
  We propose that the combination of malnutrition-related studies with most recent GIScience developments such as crowd-sourced geodata collection, (web-based) interoperable spatial health data infrastructures as well as (dynamic) information fusion approaches are beneficial to deepen the understanding of this complex phenomenon.
authors.forename: Sabrina
authors.initials: S
authors.lastname: Marx
authors.forename: Revati
authors.initials: R
authors.lastname: Phalkey
authors.forename: Clara B
authors.initials: CB
authors.lastname: Aranda-Jan
authors.forename: Jörn
authors.initials: J
authors.lastname: Profe
authors.forename: Rainer
authors.initials: R
authors.lastname: Sauerborn
authors.affiliation: Institute of Geography, Heidelberg University, Berliner Str, 48, 69120 Heidelberg, Germany. hoefle@uni-heidelberg.de.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Höfle
mesh_terms: D017954:Africa South of the Sahara / Q000453:epidemiology; D040362:Geographic Information Systems; D006801:Humans; D020407:Internet; D044342:Malnutrition / Q000453:epidemiology* / Q000517:prevention & control