Sanitation is fundamental to development. Public health officials have long known that epidemics of communicable diseases cannot be stopped without safe water and sanitation and widespread public health measures. But the percentage of people with access to sanitation has actually fallen in the developing world since 1990, as funding has declined and population has increased. 
 

What type of facility is sanitary? What is ‘convenient access’? Each country has its own definition, or more than one—often different for urban and rural areas.

The sanitation league table does not provide exact rates of access to sanitation, nor does it rank countries on this basis. Rather, the table groups countries in broad categories by percentage of people with access to sanitation according to the national definition. These definitions vary both in type of toilet facility and in its distance from the home. Because of these differences in definitions and also in data reporting methods and the quality of data, direct comparisons of countries’ achievements are difficult.

Definitions may reflect countries’ level of economic development, urbanization and resources available for sanitation. Rapid urbanization increases population densities and puts greater demands on sanitation facilities.

Some countries count ordinary pit latrines as adequate sanitation, while others count only ventilated improved pit (VIP) latrines and/or flush toilets connected to a septic tank or a sewerage system. In Uganda, for example, pit latrines are counted as sanitary, and the latest Demographic and Health Survey (DHS) shows 80% of households with access. But if pit latrines are not counted, the level of access shrinks to a mere 3%. Because of this discrepancy, the table uses data from Uganda’s sanitation surveillance system, which reported access of 57%.

Differences behind the data must be explained to understand why, for example, Tanzania, one of the least developed countries, has a rate of access to adequate sanitation above 75%, while Brazil, far wealthier and more developed, has an access rate below 50%.

Pit latrines may be adequate for rural communities but may not be appropriate for urban areas. Therefore, more urbanized countries, such as Argentina and Brazil, record only flush toilets as adequate and report lower rates of access than poorer countries, such as Kenya and Tanzania.

Discrepancies can also arise depending on whether data are gathered by routine government reporting or by surveys—both of which were used in preparing the table. The rate of access to adequate sanitation is usually determined by dividing the number of sanitation facilities in a community by the number of inhabitants. Routine reporting may, however, rely on outdated census data or fail to take into account squatter communities or public sanitation facilities that fall into disrepair. It may also not include privately built latrines.

Household surveys, on the other hand, can provide data on actual availability of sanitation facilities—rather than simply on what facilities have been provided—and have the advantage of providing direct, timely information from the field. Surveys can therefore point to problems in data obtained from routine reporting. They are, however, much more expensive than routine government reporting, may use different definitions and are subject to sampling errors and distortions.

The WHO/UNICEF Joint Monitoring Programme was established in 1990 to help countries strengthen water and sanitation data collection and evaluation. Generally, countries’ definitions have since become more restrictive and realistic, resulting in reports of lower rates of access. Just as many countries need to step up efforts to improve access to sanitation, greater standardization of definitions is needed to allow for more accurate global comparisons of progress.