PMID- 2119916
OWN - NLM
STAT- MEDLINE
DCOM- 19901102
LR  - 20220408
IS  - 0009-9147 (Print)
IS  - 0009-9147 (Linking)
VI  - 36
IP  - 9
DP  - 1990 Sep
TI  - Precision requirements for cost-effective operation of analytical processes.
PG  - 1629-32
AB  - Current performance criteria for analytical methods are often based on 
      recommendations developed many years ago. A common criterion for imprecision 
      requires that two times the standard deviation (s) of the method be less than the 
      allowable total error (TEa). Unfortunately, when this criterion is minimally 
      satisfied, commonly used control procedures cannot achieve reliable detection of 
      medically important errors. Studies of the power functions for statistical 
      quality-control (QC) procedures show that the magnitude of medically important 
      errors must be at least 3s to fall near the plateau of the power curves and be 
      readily detected by current QC procedures. For methods that just meet the 
      precision criterion 2s less than TEa, however, medically important errors will 
      fall on the rising portion of the power curves and typically be detected less 
      than half of the time. From a "reverse engineering" perspective, the 2s less than 
      TEa criterion is inadequate because it does not allow for the known performance 
      limitations (lack of sensitivity) of commonly used control procedures. A strong 
      case can be made for using a criterion of at least '4s less than TEa, which calls 
      for a twofold improvement in imprecision over, the current minimum requirements. 
      This recommendation is consistent with current industrial guidelines for process 
      capability and would lead to more reliable detection of medically important 
      errors.
FAU - Westgard, J O
AU  - Westgard JO
AD  - Department of Pathology, University of Wisconsin, Madison 53792.
FAU - Burnett, R W
AU  - Burnett RW
LA  - eng
PT  - Journal Article
PL  - England
TA  - Clin Chem
JT  - Clinical chemistry
JID - 9421549
SB  - IM
CIN - Clin Chem. 1991 Dec;37(12):2158-9. PMID: 1764808
MH  - Chemistry Techniques, Analytical/economics
MH  - Chemistry, Clinical/*economics
MH  - Cost-Benefit Analysis
MH  - Laboratories, Hospital/economics
MH  - Quality Control
MH  - Statistics as Topic
EDAT- 1990/09/01 00:00
MHDA- 1990/09/01 00:01
CRDT- 1990/09/01 00:00
PHST- 1990/09/01 00:00 [pubmed]
PHST- 1990/09/01 00:01 [medline]
PHST- 1990/09/01 00:00 [entrez]
PST - ppublish
SO  - Clin Chem. 1990 Sep;36(9):1629-32.