Verification of the EDA Concept Through an Assessment of Theoretical Failure Modes, Failure Mode Analysis, and Case Studies with Real Data - Good Cascade Impactor Practices, AIM and EDA for Orally Inhaled Products - page 273

These case studies [ 11 , 14 ] demonstrate that far from reducing the information
that is useful at diagnosing changes to OIP APSDs, EDA enriches the knowledge
base available from CI data, thereby helping the analyst make correct decisions
about the product. Although this information is contained in the collection of indi-
vidual and averaged CI APSD profi les (Fig. 9.25 ), it is less accessible as a decision-
making tool.

9.6 Conclusions

Strong arguments supporting the robustness of the EDA approach for the assess-
ment of CI-determined APSD changes have been presented, both from theoretical
considerations based on aerosol mechanics during the measurement process, failure
mode assessments based on two of the major OIP categories, and lastly from case
studies based on products that have been marketed or are in development. Although
the assumption has been that the underlying measurements were made with full-
resolution CI systems, it should be recalled that EDA can also be applied to AIM as
well as full-resolution CI data. Such an AIM-EDA approach has the potential to
combine the sensitivity of the CI data interpretation to changes in APSD described
in this chapter with the simplicity and other advantages reviewed in Chap. 5 associ-
ated with abbreviating the measurement system.

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