CO-NH2 CO-NH2 „„CO-NH2 CO-NH2

6 ANALGESIC ACTIVITY IN MAN AND IN ANIMALS
O. SCHAUMANN (402) . Numerous ingenious means of inflicting pain which is
quantifiable in mechanical, thermal, electrical or chemical units of measurement
have been devised.
All possible species, routes of administration, criteria of "effectiveness"
or "analgesic activity" and methods of symbolization and statistical analysis
have been used, and many other modifications of known methods will
undoubtedly be published in the future.
The main difficulty, however, in interpreting the various results obtained by
different authors, originates from the fact that the reproducibility and
standardization of the methods is a neglected problem. The evidence,
presented in the next chapters, shows that significantly different results have
often been obtained by investigators, claiming to use the same method. There
are several possible reasons for this:
(1) The description of the original method may have been insufficient
for the purpose of exact duplication.
(2) Unknown neglected and unexpected factors (race, food, body-weight,
handling of the animal, amount and nature of solvent, impurity in
sample, previous treatment, season, etc.) may have been responsible.
It should be more generally realized, in our opinion, that the first requirement
for an "ideal" pharmacological method is that it should be reproducible
by every investigator who follows exactly the directions given in a description
of the method. In order to find out whether such descriptions exist at all,
the whole problem of standardization of pharmacological methods should be
investigated by collaborative experimentation in many laboratories.
These considerations and restrictions should be kept in mind when reading
the following chapters.