Co-authorship network according to the income-level of the country of origin (anonymized).

<p>Network composed of 1339 authors (or nodes). Authors from high-income countries are in blue, middle-income countries in green and low-income countries in red. Nodes were resized according to the degree of centrality.</p

International collaboration by economic groups of countries (1996–2012)

<p>International collaborations were considered when the paper involved different countries, 98 in total. The combination of countries according to economic groups considered income extremes. For example, if there was a collaboration involving one high-income country and two middle-income countries, this was classified as a high- and middle-income country collaboration, not as middle and middle.</p

Co-authorship network according to betweenness centrality (anonymized).

<p>Network composed of 1339 authors (or nodes). Nodes were resized according to degree of centrality. The colour of the node was determined by its betweenness centrality. Dark blue nodes represent higher betweenness centrality. Conversely, light blue nodes represent lower betweenness centrality.</p

Size of collaborations^* in respect to number of authors, institutions and countries

<p>*Each paper with more than one author was considered to be a scientific collaboration.</p

Age-adjusted hazard ratio (95%CI) for overall mortality across categories of index of multiple deprivation.

<p>The vertical axis is plotted in the log-scale. The distances between categories in the horizontal axis correspond to the mean values for index of multiple deprivation (IMD) in England. IMD categories were based on the standard deviation (SD) from the overall score from each country (SD by country: England= 15.7, Wales= 14.3 and Scotland= 16.6). Numbers above each box indicate the corresponding hazard ratios and 95% confidence intervals. The mean and the range were calculated from the overall score from each country by IMD categories.</p

Survival curves for the lowest and highest index of multiple deprivation categories, adjusted for age, for overall and cause-specific mortality in the BWHHS, 1999-2001 to 2012.

<p>(a) All-cause, (b) all vascular, (c) all cancer, (d) all respiratory disease and (e) others. The Y-axes were truncated to 0.6 for a better visualization. The dashed lines divide the graphs into periods of four years.</p