Study Design Levels Used in Simulation
| Factor | Levels Studied |
|---|---|
| Trend with time | a. Does not change, slope (β = 0) |
| b. Changes, slope (β = −0.15) | |
| Sample sizea | a. Small: [4(0),3(6),3(12)] |
| b. Large: [10(0), 10(12), 10(24)] | |
| Shelf-life (or expiry) | 12 months for small sample size, and 24 months for large sample size |
| Intraclass correlation coefficient | ρ = 0.2, ρ = 0.8 |
| Proportion covered, P | 0.9, 0.95, 0.99, 0.9973 |
| Data used | a. RS = both release + stability data |
| b. S = stability data only | |
| Method used | a. HK = Hoffman and Kringle (2005) two-sided limits |
| b. H = Hoffman (2010) one-sided limits | |
| c. HK1= Hoffman and Kringle (2005) one-sided modification |
↵a Sample size notation is [# of lots (maximum age of lots in months)]. For example, the Small sample notated as [4(0),3(6),3(12)] consists of four lots at 0 month (i.e., release data), three stability lots at 0, 3, and 6 months, and three stability lots at 0, 3, 6, 9, and 12 months.