Background. The diagnosis of obstructive ventilatory disorders in children in Benin is not reliable despite the inclusion of ethnic correction factors for European standards (ERS-93) and the use of African-American standards (ITS-Black). Objectives. (1) Define standard values for forced vital capacity (FVC) and forced expiratory volume in the first second (FEV1) and (2) compare the FVC and FEV1 values observed in study subjects to those calculated by the ERS-93 and ITS-Black equations. Methods. FVC and FEV1 were measured using the MicroQuark Spirometer (Cosmed, Italy), and standing height was measured in 274 Beninese boys and 210 Beninese girls. The means and 95% confidence intervals for these values were calculated by univariate analysis. Results. FVC and FEV1 values calculated using the ERS-93 equations were significantly higher ( ) than the measured values from our study. The percent change between the standard values in our study and the standards calculated using the ERS-93 and ITS-Black equations revealed differences between Beninese children and children of European or African-American descent. Conclusion. The differences observed between study samples and those derived from the ITS-Black and the ERS-93 equations should be used as ethnic correction factors. 1. Introduction The diagnosis of bronchial obstruction, the early identification of lung diseases, the monitoring of lung growth, and the apogee and decline in lung function over time are all important characteristics to consider in the clinical management of respiratory disease. The assessment and management of respiratory diseases require reliable spirometry reference points for both static and dynamic lung volumes. To accomplish this, the effects of disease and of environmental influences on lung growth must be understood to avoid misdiagnoses. Ventilatory parameters observed in measurements of respiratory mechanics should be compared with spirometric reference values ？？by sex, age, height, and ethnicity in accordance with the recommendations of the American Thoracic Society and the European Respiratory Society (ATS/ERS) [1, 2]. Indeed, it is well established that these key variables affect ventilatory parameters, for example, height increases linearly with volume and pulmonary flow until the age of approximately 12 years for boys and 10 years for girls. However, the relationship between age and height varies from puberty until approximately 20 years of age [3–5]. Similarly, reference spirometry values have been established in Europeans who are aged from 18 to 70 years and who are 1.55 to
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