IPDE - Extranet Systems - World Health Organization

86 A. W. Loranger
diagnosis, as usually practiced. was 'as good as gold,' there would be no
need to improve it with semistructured interviews.
A common practice is to invoke construct validity by demonstrating
that a diagnosis agrees with that based on other interviews or inventories.
However, this has restricted meaning, because the instruments usually
sample identical content and often employ similar methods. The use of
the so-called LEAD standard (Longitudinal, Expert, and All Data)16 is
also not without its problems. It is unlikely that many uue 'experts* have
the time or inclination to want to conduct a thorough examination and
prolonged study of a large enough sample of patients to provide adequate
representation of the various PDs and the differential diagnostic
problems commonly encountered in ordinary clinical practice. The
experts would also have to adhere to the same definition of a PD and
diagnostic criteria, or there would he obvious artifactually based discrepancies.
Inevitably the experts would also have to demonstrate how much
they agree with one another.
The ultimate validation of the IPDE may prove to be a pragmatic one.
Does the interview provide more replicahle and useful answers to questions
about etiology, course, and treatment than the assessments obtained
from clinicians without benefit of the IPDE? The expectation is that it
has the potential for doing so, because it is more likely to insure comprehensive,
standardized coverage of the information required for a diagnosis.
In theory the results of the examination should also be more
generalizable and exportable than the clinical consensus of a panel of
experts at one particular facility.
There are obvious cultural variations in what is considered maladap
tive behaviour. Understandably one might question whether the PD
criteria of DSM-111-R, which were developed for use in the US, are relevant
or meaningful (valid) in other cultures. One might also wonder
whether the ICD-10 criteria, which were designed for worldwide use,
might be unduly influenced by Westem psychiatric tradition. In the study
no attempt was made to change the criteria themselves, in order to
accommodate a particular culture. However, the clinicians were
instructed to judge the meaning of the behaviour in the context of their
culture. This did not prove to be a common occurrence. Examples
include the DSM-111-R criteria pertaining to monogamous relationships
(antisocial) and harsh treatment of spouses and children (sadistic).
Surprisingly, the investigators at the various centresexpressed few reservations
about the applicability of either DSM-111-R or ICD-10 in their
own nations.