Analytical performance verification protocols and specifications of CD34 +cell enumeration by flow cytometry / 中华检验医学杂志

ABSTRACT

Objective:To investigate the analytical performance verification protocols and performance specifications of CD34+cell enumeration by flow cytometry for clinical laboratories.Methods:According to international guidelines and National Health Standard of China, we designed the performance verification protocols of CD34 +cell enumeration (including percent count and absolute count) by flow cytometry. Four quality assessment materials, three leukapheresis products and three samples of peripheral blood were selected to verify the precision, linearity, carryover, trueness and accuracy of FACSCanto Ⅱ measurement system, and the assessment criterion was set according to the detection technologies of clinical laboratories. Results:The CVs of intra-run precision of percent count and absolute count were 2.5% to 8.9% and 3.0% to 9.0%; the CVs of inter-run precision were 2.8% to 10.5% and 3.8% to 9.9%, respectively. The slopes of linearity regression equation of low range (3.6/μl to 123.6/μl) and high range (113.2/μl to 1196.3/μl) were 0.993 2 and 0.965 2, and R2 were 0.999 6 and 0.993 9, and the biases were -8.67% to 0.22%. The carryover of percent and absolute count were 0.07% and 0.00%. When percent count≤0.2% or absolute count≤20/μl, the absolute biases of trueness were in the range of ±0.006% or ±0.5/μl, and the absolute biases of accuracy were in the range of ±0.02% or ±0.9/μl; when percent count>0.2% or absolute count>20/μl, the relative biases of trueness were in the range of ±5.65%, and the relative biases of accuracy were in the range of ±8.19%. The verification results met the assessment criterion set in this study. Conclusions:The performance verification protocols and assessment criterion formulated in this study not only conform to the recommendations of domestic and foreign guidelines, but also conform to state of the detection technologies of native clinical laboratories, which can be taken as a reference of performance verification for clinical laboratories.