A set of training materials for professionals working in intervention epidemiology, public health microbiology and infection control and hospital hygiene.
Need help with your investigation or report writing? Ask the Expert. Free advice from the professional community.
You can't make decissions on this page's approval status because you have not the owner or an admin on this page's Group.
Data on case characteristics, when available, are used to compare incidence or rates between various groups of cases, for example between different ages, between sexes or between different professions. This is useful to detect outbreaks which predominantly affect a particular group. The result of these comparisons can be expressed as a relative risk (RR) and its confidence interval.
When cases and deaths are notified, the case-fatality (CF) is often a useful indicator to compute. An increase in the case fatality may alert on an increase in the severity of the disease corresponding to a specific germ (e.g. cholera when diarrhoea is under surveillance as a syndrome).
Additional information on case characteristics, such as vaccine status, is not collected routinely since it is rarely necessary for triggering a public health alert. In most surveillance systems, this type of analysis is only performed at the "response" stage (investigation), and only on an ad hoc basis.
Analysis of case characteristics may be subject to biases as notified cases may not be representative of all cases in the population:
These biases may affect the results of the analysis. Results must therefore be interpreted in the light of potential biases.
You need to be logged in to post comments.
You can log in here. You can register here if you haven't done so yet.