Luisa Agnello1, Bruna Lo Sasso2, Giulia Bivona2, Caterina Maria Gambino1, Rosaria Vincenza Giglio1, Giorgia Iacolino1, Alessandro Iacona2, Silvia Mancuso1, Anna Maria Ciaccio3, Matteo Vidali4, Marcello Ciaccio5. 1. Institute of Clinical Biochemistry, Clinical Molecular Medicine and Laboratory Medicine, Department of Biomedicine, Neurosciences and Advanced Diagnostics, University of Palermo, Palermo, Italy. 2. Institute of Clinical Biochemistry, Clinical Molecular Medicine and Laboratory Medicine, Department of Biomedicine, Neurosciences and Advanced Diagnostics, University of Palermo, Palermo, Italy; Department of Laboratory Medicine, University Hospital "P. Giaccone", Palermo, Italy. 3. University of Palermo, Palermo, Italy. 4. Unit of Clinical Chemistry, Maggiore della Carità Hospital, Novara, Italy. 5. Institute of Clinical Biochemistry, Clinical Molecular Medicine and Laboratory Medicine, Department of Biomedicine, Neurosciences and Advanced Diagnostics, University of Palermo, Palermo, Italy; Department of Laboratory Medicine, University Hospital "P. Giaccone", Palermo, Italy. Electronic address: marcello.ciaccio@unipa.it.
Abstract
BACKGROUND: The aim of the study was to accurately establish the reference interval (RI) of monocyte distribution width (MDW) in healthy blood donors by the direct method using different statistical approaches. METHODS: MDW was measured in 486 subjects. RI of MDW was calculated by the non-parametric method, the robust method and, the Harrell-Davis bootstrap method and using different tests to identify potential outliers (Dixon-Reed and Tukey). RESULTS: Lower and upper reference limits of the RI calculated by the non-parametric method were, 16.22 (90%CI 15.78-16.47) - 23.15 (90%CI 22.80-24.10) (without outlier removal), and 16.44 (90%CI 16.21-16.67) - 22.99 (90%CI 22.33-23.22) (after outlier removal). The RIs based on the robust method were, respectively, 16.29-22.98 (without) and 16.50-22.67 (with outlier removal). Finally, the RIs calculated by the Harrell-Davis bootstrap method, without or after outlier removal, were 16.19-23.24 and 16.43-22.93. Thus, the RIs obtained by the three calculation methods were very similar. Additionally, no RI partition was done since no significant gender or age association was found. CONCLUSIONS: Our results support the use of a unique RI of MDW, independently of sex and age.
BACKGROUND: The aim of the study was to accurately establish the reference interval (RI) of monocyte distribution width (MDW) in healthy blood donors by the direct method using different statistical approaches. METHODS: MDW was measured in 486 subjects. RI of MDW was calculated by the non-parametric method, the robust method and, the Harrell-Davis bootstrap method and using different tests to identify potential outliers (Dixon-Reed and Tukey). RESULTS: Lower and upper reference limits of the RI calculated by the non-parametric method were, 16.22 (90%CI 15.78-16.47) - 23.15 (90%CI 22.80-24.10) (without outlier removal), and 16.44 (90%CI 16.21-16.67) - 22.99 (90%CI 22.33-23.22) (after outlier removal). The RIs based on the robust method were, respectively, 16.29-22.98 (without) and 16.50-22.67 (with outlier removal). Finally, the RIs calculated by the Harrell-Davis bootstrap method, without or after outlier removal, were 16.19-23.24 and 16.43-22.93. Thus, the RIs obtained by the three calculation methods were very similar. Additionally, no RI partition was done since no significant gender or age association was found. CONCLUSIONS: Our results support the use of a unique RI of MDW, independently of sex and age.