Dictionary of Evidence-based Medicine.pdf

154 Dictionary of Evidence-based Medicine
(b) they do present such a known or potential problem but have been
shown to meet an appropriate bioequivalence standard
they are adequately labelled
they are manufactured in compliance with current good manufacturing
practice regulations.
Therapeutic substitution
Therapeutic substitution, also referred to as therapeutic exchange or therapeutic
interchange, refers to the dispensing of a drug of different chemical
structure to that ordered by the prescriber because it is deemed to be therapeutically
equivalent and/or more cost-effective. Therapeutic interchange
has been used for H 2 antihistamines, quinolone antibiotics and tetracyclines.
Just like generic substitution, it is a method for controlling drug
costs (Rich DS (1989) Experience with a two-tiered therapeutic interchange
policy. American Journal of Hospital Pharmacy. 46:1792-8).
Threshold analysis (see under Sensitivity analysis)
Time preference
Time preference refers to people's preference to consume now rather than
in the future, everything else remaining constant. This provides the rationale
for discounting future benefits.
Total phase
In the terminology of procedures associated with the marketing approval
of therapeutic drugs by licensing authorities, the total phase refers to the
interval between submission of an investigational new drug application
(IND) and its marketing authorization by the appropriate regulatory
agency (Food and Drug Administration in the USA, European Medicines
Evaluation Agency in the European Community).
Total purchasing
In the context of UK health care, total purchasing refers to the purchase of
hospital and community care services not covered by the fundholding
scheme, by groups of general practitioners (GPs). The purchasing is done
on behalf of patients by the GPs but the responsibility remains with the