Association between Official Development Assistance for Water and Sanitation and Countries' Needs from 2002 to 2019.

Although an enormous amount of aid has been invested in water and sanitation, few studies have analyzed the criteria used by the international community to select recipient countries and allocate official development assistance (ODA). We examined whether ODA has been allocated in proportion to water and sanitation needs and whether this has improved over the past 18 years. For water, 141 low- and middle-income countries (LMICs) and least-developed countries (LDCs) were selected, whereas 104 LMICs and LDCs were chosen for sanitation due to a lack of data. For aid disbursement, we used ODA data from the Organization for Economic Cooperation and Developments (OECD) Creditor Reporting System (CRS) from 2002 to 2019. OECD CRS data on water and sanitation are available from 2002 onward. For water and sanitation coverage, we collected data from the WHO/UNICEF Joint Monitoring Program from 2002 to 2019. We examined annual ODA trends and performed linear regression analysis adjusted for GNI per capita using log-transformed dependent variables. Neither total ODA nor ODA per capita was found to be associated with countries' needs for water and sanitation. For instance, no significant association was detected between at least basic water and sanitation coverage and total ODA per capita in 2019 (log coefficient: 0.002,