A phenomenon according to which persons with a greater-than-average risk of illness or maternity enrol in a health micro-insurance scheme in a higher proportion than that of their share of the target population and/or choose the highest levels of coverage. When individuals have no say about whether to be insured or at what level of coverage, adverse selection does not exist. Such is the case when membership is automatic and schemes offer a single level of coverage. The existence of adverse selection may jeopardize a scheme's financial viability given that benefit-related expenses risk exceeding forecasts, since they are based on estimates of consumption for the overall target population. [ref. 144]
The number of cases of a given disease as compared to all cases of disease and expressed as a percentage.
Example: If 15 per cent of the cases of disease registered by a health facility correspond to cases of malaria, then the prevalence rate of malaria is 15 per cent. [ref. 144]