Olawumi, H.ODurotoye, I. A.,Afolabi, J. K.Fadeyi, A.,Desalu, O.O.,Aderbigbe, S.A.,Babatunde, A.S.,Ernest, S.K.,Fawibe, A.E.,Salami, A.K.,Saadu, R.,Adeboye, M.A.N.,Aboyeji, A.P.2020-05-242020-05-242015Olawumi, H.O., Durotoye, I. A., Afolabi J. K., Fadeyi, A., Desalu, O.O., Aderbigbe, S.A., Babatunde, A.S., Ernest, S.K., Fawibe, A.E., Salami, A.K., Saadu, R., Adeboye, M.A.N., & Aboyeji, A.P. (2015). Reference Values of Haematological Parameters of Healthy Adults in the North Central Zone of Nigeria. East African Medical Journal; 92(8):420-425.http://hdl.handle.net/123456789/4039Background: Haematological parameters differ from one population to another due to several factors. To determine the clinical implication of the blood parameters of an individual in the state of health or disease, we need to have the knowledge of the normal reference range for that locality. Objectives: To determine the reference values of haematological parameters of apparently healthy adults in Ilorin. Design: A descriptive cross sectional study. Setting: Ilorin, North Central zone of Nigeria Subjects: Nine hundred and ten (443 males and 467 females) randomly selected normal, HIV negative individuals aged 18-65 years Results: The red blood cell count, Haemoglobin concentration, PCV and MCHC were significantly higher among males than females while the platelet count, total WBC count and absolute neutrophil count were significantly higher in females than in males. There was however no significant gender difference in the values of MCV, MCH and absolute lymphocyte count. The normal reference values obtained in this study were notably different from those that are used currently in the hospital. Conclusion: The normal reference value obtained in this study was notable different from those that are currently used in the hospital. These findings will have clinical implications regarding the adjustment of our current reference values and definitely add value to the management of patients in this part of the country. INTRODUCTION A full blood count is one of the most frequently requested investigations for routine medical checkup and preliminary investigation in the diagnosis of many diseases in every field of Medicine. It is also a common investigation used to monitor the treatment of several diseases especially in patients on cytotoxic drugs (1). The parameters in a full blood count also known as haematological parameters are affected by many different factors such as age, gender, race, altitude, exercise, pregnancyenReference ValuesHaematological ParametersHealthy AdultsNorth Central ZoneNigeriaArticle