Conclusions - Good Cascade Impactor Practices, AIM and EDA for Orally Inhaled Products - page 405

fi rst time. Finally, consideration is also given to the ways in which
data from CI-based measurements can be presented and used to derive
metrics that are representative both of aerosol “quality” and likely
deposition behavior in the human respiratory tract.
Chapter 5 : The underlying reasons for the introduction of both AIM and EDA
concepts are examined, together with the development of two different
but related purposes for CI measurements, namely, OIP quality con-
trol and related regulatory activities, and advanced uses of data as aids
in understanding how OIP aerosols interact with the human respira-
tory tract. Rationales for the application of the AIM concept to either
knowledge acquisition stream are examined, and the utility of the
EDA concept in the assessment of OIP aerosol quality is also intro-
duced. This data analysis concept, though compatible with AIM-based
systems, is applicable to both full-resolution and abbreviated impactor-
based measurements. Guidance is also given in the selection of an
appropriate AIM-based CI system, providing the foundation for the
detailed results that are presented in Chap. 10 , from experimental
evaluations of the wide range of options that are currently available.
Finally, advice is summarized in connection with the selection; appro-
priate approaches based on AIM and/or EDA are recommended for
the particular OIP aerosol assessment task in hand.
Chapter 6 : Having introduced both AIM and EDA concepts, this chapter exam-
ines their potential roles throughout the OIP life cycle from product
and method development, through in vitro support to clinical trials, to
development of the regulatory submission to commercial production.
The foundations are laid for a CI-based measurement and data analysis
management strategy that is appropriate to each stage of the life cycle,
with the idea presented of selecting “the right impactor for the right
purpose.”
Chapter 7 : The theory that underlies the EDA concept has a sound basis in mea-
surement system analysis (MSA) theory. This chapter reviews the rea-
sons for making measurements of CI-generated APSD as a critical
quality attribute for OIPs, in a product QC environment. The various
constraints that different QC metrics (e.g., stage groupings and group-
ings for FPM <5.0 mm ) impose on the measurement of APSD are dis-
cussed. These ideas are then applied to demonstrate that EDA provides
an approach to the assessment of APSDs that avoids confounding of
the key variables, MMAD and AUC , and thereby optimizing the dis-
criminating power of the EDA methodology.
Chapter 8 : Although the EDA approach to CI-generated data analysis is simple in
principle, its application in the current regulatory climate for OIPs
requires a rethink concerning the appropriateness of widely practiced
methods that rely on grouping of stages as the principal means of