Abstract

The Level of False Pass and Fail among Prospective Blood Donors as Screened by Copper Sulphate Gravimetric Method at Hossana Blood Bank, Hossana, South Ethiopia

Guracha E, Tsegaye A and Negash M

Background: Copper sulphate (CuSO4) gravimetric haemoglobin screening method has been found to erroneously include anaemic people while excluding eligible ones. Determining the rate of false deferral and false pass of prospective blood donors by this obsolete test, the routine screening method in the blood banks of Ethiopia, is the focus of this study.

Methods: In this cross- sectional study capillary and venous blood samples from 422 voluntary donors at Hossana blood bank was analyzed by copper sulphate gravimetric test and automated hematology analyzer. Data was entered in Epi-Data 3.1 and analyzed by SPSS 20. P value less than 0.05 was considered as statistically significant. Agreement between the two methods was determined using the Kappa coefficient.

Results: Overall deferral rate by the reference method was 20.1% (85/422) which was higher than copper sulphate method that also varied by blood collection site: 65 (15.4%) vs 71 (16.8%) for capillary and venous samples, respectively. The copper sulphate method resulted in respective false- pass and - fail rates of 9.2% and 4.5% (capillary blood) and 7.6% and 4.3% (venous blood). Agreement with the reference method was moderate with Kappa value of 0.53, (95% CI, 0.43-0.63, p<0.01) using capillary blood and substantial with Kappa value of 0.61, 95% CI (0.51 to 0.70), (p<0.01.) when using venous blood.

Conclusion: The high rate of false pass warrants the search for an alternative simple method to replace the old copper sulphate method. Until replaced, as it moderately agrees with the reference method, it can be retained as a primary screening tool by applying strict quality control method.

Published Date: 2019-01-29; Received Date: 2018-12-14