Diseases whose main burden is located in the lowest income regions of the world are relatively neglected in randomised controlled trials, researchers say.
Research funding agencies should prioritise funding and research activities transparently, informed by such instruments as disease burden, say the international team of researchers in an analysis published in the BMJ.
Disease for which the burden was predominantly located in low income regions had sevenfold fewer trials per million disability adjusted life years than diseases predominantly located in high income regions, the review of 4190 abstracts and 1351 randomised trials found.
Only 26% of the variation in number of trials among diseases could be explained by total disability adjusted life years and the ratio of disability adjusted life years in low income regions to high income regions.
Female infertility was the most over-represented disease or injury among randomised trials, followed by adverse effects of medical treatment and male infertility
The least studied disease with at least one trial performed was neonatal sepsis (0.023 trials per million disability adjusted life years), followed by respiratory syncytial virus, rotavirus, self harm, and neonatal encephalopathy.