Background: The complete blood count (CBC) is one of the most beneficial biological tests used in routine medical practice. The reference intervals (RIs) of the hematological parameters are of major importance for clinical orientations and therapeutic decisions and it is necessary to establish RIs that are population specific. The objective of this study was to establish population-specific reference intervals for hematological parameters among healthy adult Eritreans. Method: Using a DXH500 analyzer, CBC values were evaluated in samples taken from 401 healthy Eritreans in Asmara city, ranging in age from 18 to 60. For the blood tests, a sample of venous blood was drawn into a tube containing the anticoagulant EDTA. Data analysis was done using SPSS version 25, and a P value of 0.05 or above was deemed significant. The upper (97.5th percentile) and lower (2.5th percentile) reference interval boundaries with 95% CI were determined using a non-parametric test. The necessity for gender-based reference interval partitioning was determined using the Harris and Boyd Rule. Results: The established 95% reference intervals combined median (2.5th 97.5th percentile) were: that represent both males and females as per the suggestion of Harris and Boyd WBCs, Lymphocytes, Monocytes, Neutrophils, Eosinophils, Basophils, MCV, RDW, RDW-SD and MPV (fl) were 6.3(3.62-11.56x103/microliter), 39.53(22.10-60.55 %), 8.67(5.70-13.61 %), 49.32(27.09-69.25 %), 1.19(0.22-7.13%), 0.17(0.02-0.61%), 88.10(79.32-96.07fl), 13.50(12.50-15.90 %), 37.25(33.00-43.29%), and 9.29(7.76-11.51fl) respectively. RBCs, Hb, HCT, MCH, MCHC, and platelets were the parameters that required separate RI. Their respective median (2.5th 97.5th percentile) for males versus females were 5.40 (4.57-6.21 x106/microliter) versus 4.88 (4.25-5.61x106/microliter), 15.66 (13.56-18.13 g/dl) versus 13.50 (11.95-15.68 g/dl, 48 (42.02-53.93%) versus 42.60 (36.40-48.52%), 29.10 (26.02-34.74 pg) versus 28.30 (24.79-31.02 pg), 32.55 (31.60-36.14 g/dl) versus 32.20 (31.10-33.50 14 g/dl) and 273.15 (155.67-399.34) versus 314.35 (113.96-499.55 103/microliter). Conclusion: The reference intervals established in this study differ from currently used RIs and thus should be used for the interpretation of laboratory results in diagnosis and safety monitoring in clinical trials in Asmara

The authors have declared no competing interest.

This study did not receive any funding

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The Eritrean Ministry of Health's ethics committee granted ethical approval for this study.

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All data produced in the present study are available upon reasonable request to the authors