Characteristics of responder, non-responder and no contact identified groups
| Responder | Non-responder | No contact identified | P value | |
| Countries, no. (%) | 121 (61) | 45 (23) | 32 (16) | |
| GDP classification† | 0.18* | |||
| Low income, no. (%) | 14 (12) | 12 (27) | 5 (16) | |
| Lower middle income, no. (%) | 30 (25) | 12 (27) | 8 (25) | |
| Upper middle income, no. (%) | 34 (28) | 12 (27) | 12 (38) | |
| High income, no. (%) | 43 (36) | 9 (20) | 7 (22) | |
| Region‡ | 0.002* | |||
| Africa, no. (%) | 23 (19) | 17 (38) | 7 (21) | |
| South-East Asia, no. (%) | 8 (7) | 1 (2) | 1 (3) | |
| South and Central America, no. (%) | 19 (16) | 8 (18) | 5 (16) | |
| Western Pacific, no. (%) | 12 (10) | 4 (9) | 13 (41) | |
| Eastern Mediterranean, no. (%) | 15 (12) | 6 (13) | 0 | |
| North America, no. (%) | 3 (2) | 1 (2) | 0 | |
| Europe, no. (%) | 41 (34) | 8 (18) | 6 (19) | |
| Country population,§ median in thousands (IQR) | 10 824 (4503–43 417) | 7237 (2175–17 468) | 274 (98–1208) | <0.001** |
| Country population<18 years,¶ median in thousands (IQR) | 3744 (1081–14 144) | 3248 (798-9 500) | 113 (27–581) | 0.08** |
| Number of physicians per 100 000 population,†† median (IQR) | 158 (43–290) | 62 (8–241) | 46 (19–147) | 0.002** |
*P values were calculated using Fisher’s exact tests for categorical variables.
**P values were calculated using Kruskal-Wallis tests for continuous variables (based on Χ2 statistics with 2 df).
†World Bank list of economies (2017) (internet). World Bank. Available from: http://databank.worldbank.org/data/download/site-content/CLASS.xls.
‡Region classification based on ‘WHO regional offices’. WHO, 2017, www.who.int/about/regions/en/.
§Population, total (18 September 2017). Retrieved 9 October 2017, from https://data.worldbank.org/indicator/SP.POP.TOTL.
¶The State of the World’s Children 2016 Statistical Tables (27 June 2016). Retrieved 31 October 2017, from https://data.unicef.org/resources/state-worlds-children-2016-statistical-tables/.
††The 2016 update, Global Health Workforce Statistics, WHO, Geneva (http://www.who.int/hrh/statistics/hwfstats/).
GDP, gross domestic product.