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Clinical Chemistry and Hematology Laboratories

General Clinical Chemistry Proficiency Testing

All summary data from chemistry proficiency tests (1996 - present) are available on line. Go to the Clinical Chemistry Proficiency Test Data Base

The General Clinical Chemistry Proficiency Testing program is an approved HCFA CLIA'88 proficiency test program surveying 28 analytes including all 25 analytes listed in the Federal Register (Dept of Health and Human Services, Health Care Financing Administration. Clinical Laboratory Improvement Amendments of 1988;Final Rule. Fed. Reg. February 28, 1992;57:7001-7288).

All diagnostic clinical chemistry tests including substrates, enzymes, electrolytes, and metal analyses are included in this category. Laboratories performing one or more of the following analytes, available in the New York State proficiency test program, should apply for a permit in Clinical Chemistry: albumin, alkaline phosphatase, alanine aminotransferase, amylase, aspartate aminotransferase, bilirubin (total), calcium, chloride, cholesterol, HDL-cholesterol, LDL-cholesterol, creatine kinase, creatine kinase isoenzymes, creatinine, gamma-glutamyltransferase, glucose, homocysteine, iron, lactate dehydrogenase, lactate dehydrogenase isoenzymes, magnesium, phosphorus, potassium, sodium, total protein, triglycerides, urea nitrogen, uric acid. Laboratories issued a Clinical Chemistry permit may perform a full scope of clinical chemistry testing except in those areas defined by categories Blood pH and Gases, Therapeutic Substance Monitoring/Quantitative Toxicology, and Endocrinology.

Five samples are distributed per test event, with three test events scheduled each year. Test samples are prepared by our laboratories by the quantitative transfer of constituents to a pooled human serum base which is subsequently sterile-filtered and aliquoted. Specimens are stored frozen at -80 oC and shipped in the frozen state. Participants are challenged each survey with a series of samples containing analytes at clinically relevant concentrations.

Acceptable ranges are established using fixed criteria specified by CLIA '88, and are listed below. Referee laboratory analysis, performed concurrently with participant analysis, is used to corroborate the validity of target values and to monitor specimen integrity. Participant results falling within the following limits are considered acceptable performance. Results outside specified ranges are graded as unsatisfactory (0%).

Analyte	Acceptable Limit
Glucose	Target value ± 6 mg/dL or ±10% *
Urea Nitrogen	Target value ± 2 mg/dL or ± 9% *
Creatinine	Target value ± 0.3 mg/dL or ± 15% *
Uric Acid	Target value ± 17%
Bilirubin, total	Target value ± 0.4 mg/dL or ± 20% *
Phosphorus	Target value ± 0.45 mg/dL or ± 13% *
Calcium, total	Target value ± 1.0 mg/dL
Magnesium	Target value ± 25%
Iron	Target value ± 20%
Sodium	Target value ± 4 mmol/L
Potassium	Target value ± 0.5 mmol/L
Chloride	Target value ± 5%
Albumin	Target value ± 10%
Total Protein	Target value ± 10%
Cholesterol	Target value ± 10%
Cholesterol, HDL	Target value ± 30%
Cholesterol, LDL	Target value ± 30%
Triglycerides	Target value ± 25%
Homocysteine	Target value ± 2 µmol/L or ±15%
ALT	Target value ± 20%
AST	Target value ± 20%
Amylase	Target value ± 30%
Alkaline phosphatase	Target value ± 30%
gamma-Glutamyltransferase	Target value ± 30%
CK	Target value ± 30%
CK isoenzymes	Target value ± 3 SD
LDH	Target value ± 20%
LDH isoenzymes	Target value ± 30%
* Whichever is greater

An analyte score of 80% or greater is considered acceptable performance for a proficiency test event. Any test event analyte failure (i.e. a score of less than 80%) places a laboratory at risk of overall failure for that analyte for two subsequent surveys.

Laboratories that fail to achieve a passing score for an analyte in two consecutive test events or two out of three events are required to perform corrective action and complete a remediation program for that analyte. Remediation programs are designed specifically for each laboratory based upon the nature of the proficiency test failure.

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All summary data from chemistry proficiency tests (1996 - present) are available on line. Recent events will be available here prior to mailing results to participants. Go to the Clinical Chemistry Proficiency Test Data Base