Field evaluation of who hemoglobin color scale in West Java

Area of Science:

• Hematology
• Public Health
• Clinical Diagnostics

Background:

• Anemia diagnosis relies on accurate hemoglobin (Hb) measurement.
• Point-of-care testing methods are crucial for resource-limited settings.
• The World Health Organization (WHO) hemoglobin color scale offers a visual assessment tool.

Purpose of the Study:

• To evaluate the performance of the WHO hemoglobin color scale in a field setting.
• To compare color scale results with a gold-standard automated blood cell analyzer.
• To assess the diagnostic accuracy (sensitivity and specificity) of the color scale.

Main Methods:

• A field study was conducted in Chibubur district, Java island.
• Hemoglobin levels were assessed using the WHO Hb color scale and a Sysmex K-800 automated analyzer.
• Standardized procedures were followed for blood sample collection and color scale interpretation (30 µL blood, 60-second wait time).

Main Results:

• Hemoglobin values obtained with the color scale were generally higher than those from the automated analyzer.
• The WHO Hb color scale demonstrated a sensitivity of 23.3% (14/60) and a specificity of 96.6% (58/60).
• Discrepancies suggest potential overestimation of Hb levels by the color scale under field conditions.

Conclusions:

• The WHO hemoglobin color scale may not provide accurate quantitative Hb measurements when compared to automated analysis.
• The high specificity indicates it can correctly identify individuals without anemia, but sensitivity is low for detecting anemia.
• An additional or modified testing method is proposed to improve anemia screening accuracy using this visual tool.