September 25, 1996 - CLIAC Testimony on Quality Control

My name is Brenda McCurdy and I am here today before members of the Clinical Laboratory Improvement Advisory Committee (CLIAC) and the Centers for Disease Control and Prevention (CDC) representing the American Society for Microbiology (ASM). I am a member of the ASM's Public and Scientific Affairs Board, Committee on Laboratory Practices, and Chair of the Subcommittee on Laboratory Regulation. I am also the Microbiology Section Chief at the VA Medical Center in Detroit, Michigan. Founded in 1899, the ASM is an educational and scientific society dedicated to the promotion of the microbiological sciences and their applications for the common good. The Society represents 42,00 microbiologists who work in clinical, public health, industrial and research laboratories. Many of our members apply the Clinical Laboratory Improvement Amendments (CLIA) in their laboratories on a daily basis.

In August of 1995, the ASM presented to CLIAC results of a survey conducted to determine the rate of quality control (QC) failures for 7 common laboratory reagents used in clinical laboratories. Microbiologists were asked to report QC failures for catalase, oxidase, spot indole, coagulase plasma, and lactophenol cotton blue. These reagents were found to have failed less than 1% of the time when hundreds of lots were tested. Salmonella and Shigella antisera failed less than 2% of the time. The data presented led to the following recommendations which were supported and endorsed by CLIAC:

  1. For commercial reagents surveyed with a 99% or greater success rate, test only new lots.
  2. For Salmonella and Shigella Antisera, check new lots, and once every six months thereafter. Exception: public health labs that perform epidemiological testing should look at their own data and then decide on the periodicity
  3. For commercially prepared dropper reagents, test only new lots.

CLIAC encouraged the ASM to expand the survey to include additional reagents. This past summer, ASM sponsored another survey on quality control frequencies (see attached). The ASM contracted with Analytical Sciences Inc., of Durham, North Carolina to conduct and tabulate the results of the survey. In addition, we expanded the target audience to include more outpatient and physician office laboratories (POL). Two thousand and four hundred surveys were sent out requesting information on the failure rates for 17 reagents. Reagents surveyed included Gram stain reagents, optochin disks, bacitracin disks, cefinase disks, staph latex reagent, X and V factor strips/disks, strep latex grouping reagents, germ tube reagent, PYR disks, deoxycholate reagent, methylene blue stain, KOH fungal reagent and ALA reagent.

The results showed that 12 out of 17 reagents surveyed had failure rates of less than 1%. The remaining 5 had failure rates between 2.1% and 1%. The total lots tested was 14,731, with an overall failure rate of .3%. A total of 40 failures was reported by 18 of the 304 laboratories responding (6%). However, 4 of those 18 laboratories accounted for nearly half of all the failures. The total number of years observed for all of the reagents in all of the laboratories was 2,135. With a total of 40 failures, this translates into 1 failure every 53 years.

The results of this second survey have led the ASM to make the following recommendation regarding QC and CLIA:

For commercial reagents surveyed with a 98% or greater success rate, test only new lots.

This recommendation should lead to regulatory relief for clinical laboratories since QC frequencies will be substantially reduced without compromising public health. Of the reagents surveyed, CLIA specifies QC intervals only for Gram stains and 4 other reagents. QC frequencies for the remaining 10 reagents are not specified in the CLIA regulations. Unless a QC interval is defined, all reagents are subject to two levels of controls when prepared or opened and each day of use. The ASM is recommending that only batches or lots of those reagents surveyed be checked for reactivity at the time of preparation or receipt in the laboratory. This will result in a significant decrease in the amount of QC performed. For consistency, the 99% success rate recommended for the 7 reagents in the 1995 survey should be revised to 98% without causing any negative consequences to patient care. If approved, this change will improve the cost effectiveness of the CLIA program and of quality assurance programs in clinical laboratories.

We request that CLIAC, CDC and the Health Care Financing Administration (HCFA) consider not only this recommendation, but our previous recommendations regarding QC frequencies as they continue to review and revise the QC requirements for the final CLIA regulation. The ASM remains willing to assist CLIAC, the CDC, and HCFA with QC or any other aspect of CLIA which is under review. Thank you for your consideration.