Drug-Resistant Malaria - libdoc.who.int - World Health Organization

MONITORING / 43
input of the results into the global monitoring system;
retrieval and analysis by computer.
Processing and Analysis (at WHO Headquarters)
33 000 in vitro test forms have been printed; 30 150 have
been distributed, and 341 completed forms have been returned to
WHO Headquarters.
The number of completed forms received by mid-198l at WHO
Headquarters is quite small. The majority of the forms (177 out
of 341) pertain to results obtained in 1978-1980. The proportion
of reported failures is high on the average, but varies widely
between countries.
Some of the forms received are incomplete, and some are
incorrectly filled.
Table 5 shows the number of schizonts in the control counts
of the in vitro macro test. There is wide variation and there is
obviously a need for defining the minimum acceptable number of
schizonts in the controls (see also page 35, paragraph f).
The analysis of the data in WHO Headquarters B being
undertaken jointly by the Malaria Action Programme and the Units
of Data and Text Process i ng and Health S tat is t ical Methodology.
The following technical points are under consideration.
the definition of cut-off points for the classification
of individual test results;
the study of alternati"e methods of combination of the
results from a group of tests;
the development of alternative models of the doseresponse
relationship (e.g. the log-normal distribution
of the effective dose) and of methods for fitting such
models to the data (e.g. the method used for the response
of vectors to insecticides);
the selection of alternative tests of significance of
the difference between two or more groups of tests;
the mapping of results.
In order to function optimally, closest coordination will be
required at national level in transmitting relevant information to
the WHO Regional Offices and Headquarters. Whether a summary of
information about the distribution and level of resistance could
be supplied more frequently to workers in the field remains to be
determined. The central (global) monitoring involves an inevi-