Revista Peruana de Medicina Experimental y Salud Pública
Print version ISSN 1726-4634
FLORES-TORRES, Jessica et al. Differences between observed and estimated by hematocrit hemoglobin and its relevance in the diagnosis of anemia among coastal population in Venezuela: analysis of the second national study of human growth and development (SENACREDH). Rev Peru Med Exp Salud Publica [online]. 2011, vol.28, n.1, pp. 47-53. ISSN 1726-4634. http://dx.doi.org/10.1590/S1726-46342011000100008.
Objectives. To evaluate the differences between the observed hemoglobin levels and those estimated based on hematocrit in the context of the 2nd National Study of Human Growth and Development of the Venezuelan Population (SENACREDH). Materials and methods. 6,004 individuals were chosen by a probabilistic multistage cluster sampling representing 7,286,781 inhabitants from North Central Coastal area (Vargas, Carabobo, Capital District, Aragua and Miranda). Means of observed and estimated hemoglobin (hematocrit/3) were compared, using t test for related samples and linear regression. Results. Mean difference between the values of observed and estimated hemoglobin was -0.3446 ±0.0002 (p<0.001); significantly overestimating the hemoglobin values. Regression models of hemoglobin on hematocrit showed an r2=0,87. In order to correct the estimation, we propose a new formula for calculating hemoglobin based on haematocrit values: estimated hemoglobin=(Haematocrit/3.135)+ 0.257. Conclusions: There is an overestimation of hemoglobin levels from hematocrit levels and therefore an underestimation of the prevalence of anemia; however, a high positive correlation between them was found, allowing modeling for achieving a better estimation of the hemoglobin from the hematocrit value.
Keywords : Haemoglobin; Hematocrit; Estimation techniques; Anemia; Venezuela.