Method Verification Part II TDLM Workshop · TDLM Symposia on Importing a Method – Degrees of importing – Using available data – Depth of verification – Ongoing competency

Method Verification Part IITDLM Workshop

John Szpylka, Ph.D.Technical Manager

Medallion Laboratories

AOAC Int’l Annual MeetingDallas, TX

September 2008

Last Year Started It All . . .

TDLM Symposia on Importing a Method– Degrees of importing– Using available data– Depth of verification– Ongoing competency tracking

Kicked off ALACC Guidance Document– Free on AOAC Website

Why Import A Method?

All the method development work has been done.Method performance understood.

Why Import A Method?

“Official” methods used to settle disputes.Inter-laboratory proficiency testing may already be in place.

Once Imported . . .

Must show you can do the method correctly at your site!

Degrees of Importing Methods

Performing the method exactly as written“Slightly” modifying the methodModifying the Method

Matrix Application

%CARBOHYDRATES0%100%

J. AOAC, 83 (2), 413 (2000)“The Referee”, AOAC Int’l, July 1993

Ready To Use Methods

Slightly modified– It’s always wise to have supporting data

You Never Know!

– Prove or state that modifications have no or understood effect

– Must have supporting documentation– May use validation data

Ready To Use Methods

Modified– Supporting data is a must!– Examples

different column,different detector,change of sample weights, dilutions or other sample preparation steps,solvent switch.

Verification is a “Mini-Validation”

Pull method performance during original validations (SLV and MLV)– See if you can repeat performance

To evaluate matrix effects

Analyst CompetencyTraining– Establish a written list of steps to document the training

procedure.

Our labs require– 7 replicates of a known NIST or Internal Reference Material, or– 7 side-by-side with expert.– Optional spike/recovery and/or matrix challenge.

Compare average, st. dev., and statistical analyses (ANOVA or t-Test).

Ongoing Demonstration ofMethod Performance

Participate in Proficiency testing ProgramDuplicate analysesControl Chart

Ongoing Demonstration ofMethod Control

Date/Time

Mea

sure

men

t

Average

+ 1 std dev

+ 2 std dev

+ 3 std dev

- 1 std dev

- 2 std dev

- 3 std dev

Takeaways

Importing a method is truly an adoption– Be prepared to adopt– Welcome it to your home– Take care of it– Keep it healthy– Be prepared for it to grow

This Year Goes tothe Next Level

Take what I learned last yearTake the ALACC Guidance documentShow Me How!

Thank You!Let’s Get Started!!