Evaluation of the TEST 1 erythrocyte sedimentation rate system and intra- and inter-laboratory quality control using new latex control materials.
BACKGROUND
The erythrocyte sedimentation rate (ESR) test has been considered to be a simple procedure, not requiring quality control (QC). However, QC is essential for accuracy and precision. We evaluated the TEST 1 ESR system and performed QC procedures using newly developed latex control materials in three hospitals.


METHODS
Using tripotassium ethylenediaminetetraacetic acid blood samples (n=184), we compared TEST 1 ESR values with Westergren ESR data and evaluated intra-assay precision. Three levels of latex control materials were used to assess inter-assay precision. Reference range assessment was done using samples from 220 healthy individuals. Inter-laboratory QC with latex control materials in three hospitals was performed.


RESULTS
Correlation between TEST 1 ESR and Westergren ESR results was good (p<0.001). Intra-assay precision [coefficients of variation (CV) 6.6%-21.7%] with patient samples and inter-assay precision (CV 0.0%-6.8%) with latex control materials were satisfactory. The reference ranges of 2-10 mm/h for males and 2-19 mm/h for females were established. Inter-laboratory QC data with latex control materials in three hospitals demonstrated good accuracy and satisfactory precision (CV 0.0%-14.4%).


CONCLUSIONS
Our results demonstrate that the TEST 1 QC is reliable and the latex control materials are valuable for inter-laboratory proficiency testing.
Cha
Choong-Hwan
CH
Department of Laboratory Medicine, University of Ulsan College of Medicine and Asan Medical Center, Seoul, Korea.
Cha
Young Joo
YJ
Park
Chan-Jeoung
CJ
Kim
Hyun Kyung
HK
Cha
Eun-Jong
EJ
Kim
Duck Hee
DH
Honghoon
Jung
Jae-Seol
JS
Kim
Mi-Jung
MJ
Jang
Seongsoo
S
Chi
Hyun-Sook
HS
Lee
Dong Soon
DS
D000293:Adolescent; D000328:Adult; D000368:Aged; D001799:Blood Sedimentation; D005260:Female; D006801:Humans; D007755:Laboratories, Hospital / Q000592:standards*; D007840:Latex / Q000737:chemistry*; D008297:Male; D008875:Middle Aged; D011786:Quality Control; D012016:Reference Values
D007840:Latex