Various considerations regarding vital capacity, as observed in a study of 225 men and 238 women at the Mayo Clinic, have already been presented. It became apparent that certain more general factors were repeated with such constancy that they must be considered in the interpretation of all estimations. Our observations regarding the relative importance of these factors are reported here.
It was anticipated that the vital capacity of the women of our series would be less than that of the men. We found in our group, which comprises the types of patients usually seen in ordinary practice, that the formula of West1 was more suitable because of the ease of estimation and exactness. This formula takes into consideration the body surface measurements and a constant that varies with sex. Such constants as were proposed by West agreed with our findings, and we believe are best used when developing normals