Accuracy and Use of WHO Hemoglobin Color Scale for Diagnosis of Anemia Among Pregnant Women by Health Care Providers in Periurban Settings in Karachi, Pakistan

Abstract

The study assessed the diagnostic accuracy of the Hemoglobin Color Scale (HCS), comparing clinical signs assessment technique (CSAT) of health care providers against the gold standard of laboratory hemoglobinometry. A cross-sectional validation study was conducted among 194 pregnant women located in 2 towns of periurban settings in Karachi, from June 2012 to February 2013. Anemia was assessed by HCS and CSAT by health care providers and compared with laboratory hemoglobinometry. The sensitivity and specificity of HCS were 70.9% (95% CI = 62.7-78.3) and 49.1% (95% CI = 35.1-63.2); for CSAT they were 95.7% (95% CI = 91.0-98.4) and 5.7% (95% CI = 1.2-15.7), respectively. The area under the curve for HCS for diagnosis of anemia was 0.60 (95% CI = 0.52-0.66), compared with 0.50 (95% CI = 0.43-0.57) for CSAT ( P = .01). The accuracy of HCS is better than CSAT for assessing anemia by health care providers among pregnant women.