Wayne Taylor

Dr. Wayne A. TaylorJoyce M. Hansen ABSTRACT ISO 11137 (1995), “Sterilization of Health Care Products – Requirements for Validation and Routine Control – Radiation Sterilization”, provides sampling plans for performing initial verification dose experiments and quarterly dose audits.  Alternative sampling plans are presented which provide equivalent protection.  These sampling plans can significantly reduce the cost […]

INTRODUCTION An understanding of statistical principles and how to apply them is critical to ensuring compliance with FDA requirements, such as those in the current and July working draft of the good manufacturing practices (GMP) regulation.   Indeed numerous Form 483’s issued by FDA following GMP inspections have cited sampling plans for final, in-process, and receiving

Dr. Wayne A. Taylor For the OC curve, AQL, and LTPD of a sampling plan to be valid, one must obtain representative samples of the lot.  Failure to select representative samples can seriously compromise the sampling plan’s protection.  Consider the analogy of dealing cards to obtain a fair hand.  If the deck is thoroughly shuffled,

Dr. Wayne A. Taylor Mil-Std-105E indexes sampling plans by AQL, Levels of Inspection, and lot size.  It is a common misconception that 105E includes lot size because “larger lots require more samples to obtain the same level of protection.”  In actuality, 105E takes more samples from larger lots in order to get better protection.  Figure 1

Dr. Wayne A. Taylor Numerous 483’s issued by the FDA have cited sampling plans as not being “statistically valid”.  So what is required of a sampling plan to be statistically valid?  Selecting statistically valid sampling plans is a two-part process.  First, one must determine an appropriate objective for the inspection.  Second, one must select a

Dr. Wayne A. Taylor It is common practice to classify defects accordingly to their severity and then to assign each category an acceptable quality level (AQL).  How justified is this practice and what guidelines can be given in assigning AQLs?  The answer to this depends on how AQL is interpreted.  Most generally the AQL is