Table 1.

Potential explanatory variables investigated

Indicator	Description
Number of fixed facilities/million population	We examined this variable in 2 different ways: first as a categorical variable: between 0 and 1; between 1 and 2; 2 or more. We also examined it as a dichotomous variable: no facilities; any facilities.
Presence of a dedicated eye theatre in at least one of the facilities	Dichotomous variable: Yes; No.
Number of surgeons/year/million population	To calculate number of surgeons, all surgeons stationed full time in the district during the 5 years were included; their contribution was weighted by the number of years (or fraction) they were there and this was averaged over 5 years.
Presence of functioning biometry in at least one facility	Dichotomous variable: Yes; No.
Surgical outreach: did any take place within the district?	Dichotomous variable: Yes; No.
Was there a manager for the site?	Dichotomous variable: Yes; No.
Was there an NGO hospital in the district?	Dichotomous variable: Yes; No.
Was there an eye NGO supporting activities within the district?	Dichotomous variable: Yes; No.
GDP per capita	Gross domestic product per capita in US$ by country for closest year of survey [16]
Health expenditure per capita	Health expenditure per capita in US$ by country for closest year of survey [17]
Population density	District population/district area in square meters