The INDEPTH Executive Director joins the debate on the case for generalisability over representativeness

In a new blog just published in the International Journal of Epidemiology (IJE), Eleonora Uphoff, Neil Small, Rosie McEachan and Kate Pickett discuss “The relevance of a local cohort: the case for generalisability over representativeness.”

The researchers write: “For some years, our research has been based in the city of Bradford in northern England. We are often asked to justify our research setting. There seems to be a concern that a cohort population that is not representative of the nation as a whole or of the ‘average person’ cannot produce valuable insights beyond its local setting. While such concerns are not new, they now seem more present, perhaps due to the rise of Big Data or the increased sharing of and access to data from national surveys and cohorts. Do these reservations represent a push for representativeness and generalisability in epidemiology? If so, this might come at the expense of research aiming to paint a more detailed picture of population health.”

In his reply, Osman, the INDEPTH Executive Director wrote: “You have addressed an issue the INDEPTH Network of Health and Demographic Surveillance System (HDSS) field sites in low- and middle-income countries have been grappling with for decades. We have described our dynamic longitudinal population cohorts [Sankoh O, Byass P. (2012). The INDEPTH Network: filling vital gaps in global epidemiology. Int J Epidemiol 41(3):579-88.] We have presented lessons from history in terms of representatives and the value of the cohorts. [Byass P, Sankoh O, Tollman SM, Högberg U, Wall S. (2011). Lessons from history for designing and validating epidemiological surveillance in uncounted populations. PLoS One 6(8):e22897] Recently, we looked at how generalisable are the estimates from our cohorts. [Bocquier P, Sankoh O and Byass P (2017). Are health and demographic surveillance system estimates sufficiently generalisable? Global Health Action, 2017 Vol. 10, 1356621 https://doi.org/10.1080/16549716.2017.1356621]. We work closely with the communities. We should continue to do our work and do it with scientific rigour.” Read more