Broken Record Department

August 22, 2007

A recent Letter in Clinical Chemistry (2007;53:1715-1716) is another in the series that advocates using the right model for assay analytical performance (see this essay). Unfortunately, I didn’t see an error in the proofs. The sentence, “Because neither controls nor pooled samples are used in a proficiency survey, random patient interferences cannot be estimated.” Should be “Because either controls or pooled samples are used in a proficiency survey, random patient interferences cannot be estimated.”

This Letter is about creatinine and the authors replied (2007;53:1716-1717). All of this is quite similar to an earlier Letter about glucose in Clinical Chemistry (2001;47:1329-30) and the authors’ reply (2001;47:1330-31).

Using the right model creates some experimental difficulties, but it is still worth it.


CAPA versus FRACAS

August 21, 2007

CAPA – Corrective Action Preventative Action
FRACAS – Failure Reporting And Corrective Action
FMEA – Failure Mode effects Analysis

Unlike FMEA, some (probably many) people have never heard of FRACAS. When I was explaining FRACAS to some people, someone said “oh that’s CAPA, we do that now.” Although CAPA and FRACAS share features, there are key differences.

Timing – FRACAS deals with products before release for sale, and CAPA with products after release for sale. FRACAS however, can also be continued after products are released.

Responsibility – In medical device companies, FRACAS is usually conducted by R&D and CAPA by service and manufacturing. Whereas, this may not sound like a big difference, it is. For example, service is more concerned with keeping customers happy than with corrective action.

Data source – In CAPA, there are two data sources, (customer) complaints and (manufacturing) nonconformities. This sets up the possibility for two CAPAs, which may not talk to each other; namely, a CAPA in manufacturing to deal with nonconformities and a CAPA by service to deal with customer complaints. In a FRACAS that is conducted before release for sale, the data source is “events”. An event is an observed action that has the potential to cause harm, increased cost, a return, a complaint, and so on. Note that not all events will lead to complaints. For example, a clinician may disregard an erroneous result and not complain about it.

Metrics – While anything is possible, the reliability growth management metrics associated with FRACAS are almost never used with CAPA.

Regulations – FDA requires medical device companies to have procedures in place to address nonconformities and complaints. This is traditionally handled by CAPA. There is no requirement for FRACAS.

To sum up, is CAPA the same as FRACAS? No, not by a long shot.