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Table.3 Lamba, Mu and Sigma (LMS) equations for spirometric indices of Cameroonian

From: Spirometric reference equations for Cameroonians aged 4 to 89 years derived using lambda, mu, sigma (LMS) method

Spirometric indices Males Females
FEV1, L
 Mu Exp[− 9.47 + 2.03*ln(Height) + 0.05*ln(Age) + Mspline] Exp[− 9.28 + 2.02*ln(Height) − 0.04*ln(Age) + Mspline]
 Sigma Exp[− 2.25 + 0.13*ln(Age) + Sspline] Exp[− 2.14 + 0.11*ln(Age) + Sspline]
 Lambda − 3.50 + 1.36*ln(Age) + Lspline 1
FVC, L
 Mu Exp[− 10.10 + 2.15*ln(Height) + 0.09*ln(Age) + Mspline] Exp[-9.60 + 2.08*ln(Height) + 0.01*ln(Age) + Mspline]
 Sigma Exp[− 2.13 + 0.10*ln(Age) + Sspline] Exp[− 2.05 + 0.09*ln(Age) + Sspline]
 Lambda − 2.59 + 1.01*ln(Age) + Lspline 1
FEV1/FVC
 Mu Exp[0.58 − 0.11*ln(Height) − 0.05*ln(Age) + Mspline] Exp[0.29 – 0.05*ln(Height) – 0.06*ln(Age) + Mspline]
 Sigma Exp[− 3.41 + 0.22*ln(Age) + Sspline] Exp[− 3.50 + 0.27*ln(Age) + Sspline]
 Lambda 1 1
FEF25-75%
 Mu Exp[− 7.34 + 1.60*ln(Height) + 0.15*ln(Age) + Mspline] Exp[− 8.30 + 1.81*ln(Height) + 0.09*ln(Age) + Mspline]
 Sigma Exp[− 2.14 + 0.32*ln(Age) + Sspline] Exp[− 1.77 + 0.19*ln(Age) + Sspline]
 Lambda 0.02 + 0.08*ln(Age) + Lspline − 0.54 + 0.32*ln(Age) + Lspline
  1. Xspline: age spline for Mu, Sigma or Lamda