Overview :

The Forced Midexpiratory Flow Rate (FEF25-75%) can be predicted in pediatric patients based on height and other physical characteristics.

NOTE: Quanjer et al provides many additional equations for FEF25-75% (page 229s).

Linear Equations Based on Height

FEF25-75% in liters/second for males 5-18 years old and 42-59 inches tall (Dickman) =

= (0.094 * (height in inches)) - 2.614

FEF25-75% in liters/second for males 5-18 years old and 60-78 inches tall (Dickman) =

= (0.126 * (age in years)) + (0.135 * (height in inches)) - 6.498

FEF25-75% in liters/second for females 5-18 years old and 42-59 inches tall (Dickman) =

= (0.087 * (height in inches)) - 2.389

FEF25-75% in liters/second for females 5-18 years old and 60-78 inches tall (Dickman) =

= (0.083 * (age in years)) + (0.093 * (height in inches)) - 3.499

FEF25-75% in liters per second (Polgar and Promadhat) =

= ((2.621 * (height in cm)) - 207.7) / 60

Natural Logarithm

FEF25-75% in liters per second (Wang et al) =

= EXP((B * (LN(height in meters))) + A)

Dickman ML, Schmidt CD, Gardner RM. Spirometric standards for normal children and adolescents (ages 5 years thorugh 18 years). Am Rev Resp Dis. 1971; 104: 680-687. (Table 3, page 684).

Hsu KHK, Jenkins DE, et al. Ventilatory functions of normal children and young adults - Mexican-American, white and black. I. Spirometry. Journal of Pediatrics. 1979; 95: 14-23.

Polgar G, Promadhat V. Pulmonary function testing in children. WB Saunders. 1971. page 211.

Quanjer PH, Stocks J, et al. Compilation of reference values for lung function measurements in children. Eur Respir J. 1989; 2 (Supplement 4): 184s - 261s.

Wang X, Dockery DW, et al. Pulmonary function between 6 and 18 years of age. Pediatric Pulmonology. 1993; 15: 75-88.

Wanger J. Pulmonary Function Testing. A Practical Approach. Second Edition.  Williams & Wilkins. 1996. Table A6.3, page 285.