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)
|
Boys - Age in Years
|
A
|
B
|
|
8
|
0.264
|
1.505
|
|
9
|
0.308
|
1.443
|
|
10
|
0.290
|
1.557
|
|
11
|
0.242
|
1.738
|
|
12
|
0.165
|
1.982
|
|
13
|
0.007
|
2.396
|
|
14
|
0.014
|
2.483
|
|
15
|
0.241
|
2.163
|
|
16
|
0.503
|
1.764
|
|
17
|
0.762
|
1.368
|
|
18
|
0.678
|
1.528
|
|
Girls - Age in Years
|
A
|
B
|
|
8
|
0.247
|
1.668
|
|
9
|
0.254
|
1.710
|
|
10
|
0.195
|
1.933
|
|
11
|
0.161
|
2.091
|
|
12
|
0.185
|
2.120
|
|
13
|
0.294
|
1.976
|
|
14
|
0.450
|
1.711
|
|
15
|
0.581
|
1.486
|
|
16
|
0.654
|
1.366
|
|
17
|
0.688
|
1.290
|
|
18
|
0.520
|
1.622
|
