Index
A report on a series of patients with an outcome of interest. No control group is involved.
A systematically developed statement designed to assist clinician and patient decisions about
appropriate health care for specific clinical circumstances.
Involves identification of 2 groups (cohorts) of patients, one which received the exposure of interest,
and one which did not, and following these cohorts forward for the outcome of interest.
Interventions other than the treatment under study that are applied differently to the treatment and
control groups. Cointervention is a serious problem when double blinding is absent or when the use of
very effective non-study treatments is permitted.
Quantifies the uncertainty in measurement. It is usually reported as a (95% CI 5-15), which is
the range of values within which we can be 95% sure that the true value for the whole population lies.
For example, for an NNT of 10 with a 95% CI of 5 to 15, we would have 95% confidence that the true
NNT value lies between 5 and 15.
The proportion of patients in the control group who experience the studied event.
Assesses whether the cost of an intervention is worth the benefit by measuring both in the same units;
monetary units are usually used.
Measures the net cost of providing a service as well as the outcomes obtained. Outcomes are reported in
a single unit of measurement.
The administration of 2 or more experimental therapies one after the other in a specified or random
order to the same group of patients.
The observation of a defined population at a single point in time or time interval. Exposure and
outcome are determined simultaneously.
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Last modified on: 16-Dec-04