Evaluation of copper sulfate method for screening anaemia

ABSTRACT

The haemoglobin values of 102 blood samples were determined by 3 different observers; the first two observers using the copper sulfate method, and the third observer using the cyanmethaemoglobin method. The sensitivity and specificity of copper sulfate method was callculated at haemoglobin levels of 80 g/l and 100 g/l with comparison to the cyanmethaemoglobin method. At 80 g/l level, it was found to be 100 percent sensitive with a specificity of 70 percent. At 110 g/l level, the sensitivity was reduced to 82 percent while the specificity increased to 100 percent. The numbers of cases that were either correctly or incorrectly diagnosed by each observer were not significantly different and a good agreement (Kappa statistic = 0.82, 95 percent Confidence Intervals 0.77 to 0.87) was found between the two observers. The copper sulfate method was found to be reasonably accurate for screening anaemia.