# MODIFICATIONS TO 

# EXISTING AOAC OFFICIAL METHODS

SM 2011 UDM/OECD Technical Workshop U.S. Environmental Protection Agency 

### Fort Meade, MD November 15 & 16, 2011 

### Jafrul Hasan OPP Microbiology Laboratory, EPA

# Editorial Changes • 

### An editorial change is a correction or clarification of language or expression, and no study data are needed • 

### No method validation is required, but written record of action will be filed • 

### If a method is modified editorially, it retains its First or 

### Final Action Status • 

### The AOAC Methods Committee on Antimicrobial Efficacy 

### Testing (Committee M) must approve editorial changes AOAC INTERNATIONAL Official MethodsSM of Analysis Program Manual, Part 5, 2004 AOAC INTERNATIONAL 2

## Editorial Changes – Examples • Addition of non -technical information for consistency • Updating of non -technical footnote or reference information • Changes to titles of sections, tables, and figures • Rearrangement or renumbering of sections, tables, and figures • Minor changes in sentence structure that does not change the original intent • Corrections of spelling or punctuation • Addition of AOAC general safety caveat for materials and apparatus • Correction of typographical errors that would not have otherwise affected the technical interpretation of the method AOAC INTERNATIONAL Official MethodsSM of Analysis Program Manual, Part 5, 2004 AOAC INTERNATIONAL 3

# Minor Change • 

### A minor change in procedural parameters is one that does not affect the methods performance and does not require new in- house data • 

### By scientific judgment of the Methods Committee, literature or historical data are sufficient validation • 

### A method with a minor change retains its First or Final action status • 

### The Methods Committee must approve minor changes AOAC INTERNATIONAL Official MethodsSM of Analysis Program Manual, Part 5, 2004 AOAC INTERNATIONAL 4

# Procedure Modification
• A procedure modification that does not change the principle of the method but may affect the performance parameters requires an in -house comparative study of the old and new procedure that demonstrates equivalent or improved method performance • A comparative study can be in -house or multi - laboratory, but must be of sufficient scope to establish equivalency of performance as determined by the Methods Committee • The comparison may take place against original collaborative study data • The Methods Committee must approve a procedure modification AOAC INTERNATIONAL Official MethodsSM of Analysis Program Manual, Part 5, 2004 AOAC INTERNATIONAL 5

# Procedure Modification • 

### P rocedure modifications include changes in the procedure, instrument, reagent, or parameter that does not change the principle of the method but may affect the performance parameters • 

### A modified First Action method receives a new date of First Action; a modified Final Action method reverts to 

### First Action • 

### Procedure modifications will be listed in Changes in Official Methods SM 

### and the method will be modified • 

### Method status will also be revised AOAC INTERNATIONAL Official MethodsSM of Analysis Program Manual, Part 5, 2004 AOAC INTERNATIONAL 6

# Modifications to Existing Official Methods SM
• All procedures for method approval must be followed, including submission of study protocol • The approved revised (new) method will be included in the Inside Laboratory Management ( Changes in Official Methods SM), along with notice of Repeal or Surplus status of replaced (old) method • Statistical performance parameters listed with a method remain unchanged with a method modification unless the study of the modification allows the generation of new performance parameters AOAC INTERNATIONAL Official MethodsSM of Analysis Program Manual, Part 5, 2004 AOAC INTERNATIONAL 7