Investigation and improvement of urine albumin measurement in clinical laboratories in Tianjin / 中华检验医学杂志

ABSTRACT

Objective To investigate the situation of urine albumin measurement of clinical laboratory in Tianjin.Methods Control materials from patient mixed urine samples were made to validate precision in the clinical laboratories in Tianjin.Reference Material ERM-DA470K was prepared as the first external quality assessment ( EQA) sample, and the bias between laboratories was calculated.Then we give some advice about the methods of routine maintenance, calibration, standardized operation, internal quality assessment and so on to the laboratories which were not qualified in the first EQA.Then the second EQA was carried out and CV and bias were culculated.Results 52 clinical laboratories has 12 series of instruments and 17 series of reagents.The precision research showed that most laboratories ( 93.55%) had good precision for urine albumin measurement, while CV of inter-laboratory was great:the range of low level of control sample was 8.91 -43.95 mg/L, 34.46% for CV; and the high level was 36.32 -281 mg/L, 28.51% for CV.Only 36.5% laboratories were qualified in the first EQA. The qualified rate for nephelometry and turbidimetry was higher (55.6%, 42.9%).The qualified rate of trueness verification was 58.6%in the second EQA, and the CV between laboratories was significantly decreased, Inter-laboratory CV of the five samples were:19.83%, 13.57%, 13.41%, 13.08%, 11.37%. The qudified rate for nephelomety and turbidimetry was 71.4% and 56.3%.Conclusions There are a mide variety of measurement systems of urine albumin in Tianjin, and the CV between these systems is great.Clinical laboratory should strengthen the laboratory standardization operation and upgrade calibration testing to improve the testing consistency.