Variability And Accuracy Of Sahli’s Method In Estimation Of Haemoglobin Concentration
Variability And Accuracy Of Sahli’s Method In Estimation
Keywords:
Haemoglobin, Sahli’s Method, Haemiglobincyanide Method, DhuleAbstract
Background: Haemoglobin concentration provides information about the status of anaemia in the population. Haemoglobin estimation is the routine and frequently performed screening haematological test of laboratory services. The Type of methods used and sites of collection of blood samples has found to make differences in haemoglobin concentration. The methods used in routine measurement are needed to be adjusted to obtain comparability with the haemiglobincyanide method. So the present study was undertaken with a objective to test the reliability of Sahli’s method in estimation of haemoglobin concentration and standardizing it in district hospital laboratory of Dhule in Maharashtra. Material & Methodology: Haemoglobin concentration (gm/dl) in blood is compared in 173 apparently healthy medical college students within 18 to 23 years age. Results from Sahli’s method were compared to Haemiglobincyanide (HiCN) method within capillary and venous blood of same subjects. Results: Sahli’s method has lower values than Haemiglobincyanide method with mean difference of 0.62gms/dl(95%CI; 0.51 to 0.73, p<0.01) in capillary blood and 1.1gms/dl(95%CI; 0.92 to 1.26, p<0.01) in venous blood. By Sahli’s method’s ability to diagnose anaemia has sensitivity of 83.7% & 90% and specificity of 63.2% & 60.2% in capillary & venous blood respectively. Sahli’s method has significant (p<0.01) positive correlation coefficient in capillary blood & venous blood. Variability of haemoglobin concentration in Sahli’s method is less in capillary blood then venous blood in caparison to HiCN method. Interpretation & conclusion: Sahli’s method had lower values of haemoglobin in capillary and venous blood compared to HiCN method. Haemoglobin concentration was lower in capillary blood than venous blood by both methods. For Accuracy of Sahli’s method the correction factor should be considered to ensure comparability of results with the reference method.
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