In public health, it is important to evaluate programmes (series of activities to achieve specific objectives in specific target groups) in research, surveillance, services, education and policy; in other words, to determine as systematically and objectively as possible the relevance, effectiveness and impact of programmes with respect to their objectives.1 It has been suggested that evaluation should be a built-in component of public health programmes.2

The basic principles of evaluation are information and expectation. Information can be obtained using the method of surveillance.1 3 4 Important steps in information include deciding on the list of indicators to be monitored and making sure that pertinent information is available. Even …