FDA QSIT Sampling Plans
Abstract: This brief uncovers a significant error in the tables of sampling plans on page 107 of the FDA’s Guide to the Inspection of Quality Systems – QSIT Quality Systems Inspection Techniques (1999). The 95% confidence table actually provides 97.5% confidence, and the 99% confidence table provides 99.5% confidence. However, the table on page 90 of Statistical Procedures for the Medical Device Industry (2017) corrects the 95% confidence table from QSIT, providing you with the accurate and reliable information you need for compliance inspections.
Looking for some actual references to binomial staged sampling plans that can be leveraged now that QSIT has been retired by FDA.
The QSIT Guidance Document has been retired. The table at the end of the guidance with sample sizes contained an error, as described in the article FDA QSIT Sampling Plans. The FDA removed all references to this table from their website as well. This article includes a corrected table, which can also be found in the Effectiveness Procedure in Statistical Procedures for the Medical Device Industry. The approach is still valid when using the corrected table.