Table 2.

Underestimation, its components/dimensions with definitions and determinants.

Failure to capture all cases			Definition	Determinants
Underestimation	Under-ascertainment		Infected subjects do not seek health care	Health literacy, disease perception, perceived health needs, cultural and religious factors, legal, administrative, and financial barriers
	Underreporting	Under-diagnosis/under-detection	Disease status not diagnosed/misclassified	Measurement error, lack of knowledge concerning testing and/or interpretation of tests
		Under-notification	Diagnosis not transmitted to the surveillance and notification system	Reporting/notification policies