Performance Characterization of EDA and Its Potential to Improve Decision Making in Product Batch Release - Good Cascade Impactor Practices, AIM and EDA for Orally Inhaled Products - page 201

Fig. 8.24 Process for establishing assumed limits for construction of OCCs: the limit is defined
by the value of MMAD corresponding to the intersection of the selected R 2 value (in this case 0.9)
and the goodness-of-fit curve

Comparison of Ideal APSD vs Limiting Quality Cases
50

Variable
Norm
Lower
Upper

40

R 2 =0.9

30

20

10

0

0123
Aerodynamic diameter ( m m)

456789

Fig. 8.25 Cumulative mass-weighted APSDs for OIP product w9j601 illustrating target and limit-
ing APSDs derived with R 2 set at 0.9

Corresponding and equivalent limits for the metrics of interest in the context of
EDA and “stage groupings” could be established primarily from these limiting
cumulative APSDs, once the limits were established in terms of MMAD and the cor-
responding extreme cumulative APSDs were computed. Figure 8.27 tracks the ideal