Derenzo[x_]=.5*Exp[-((83*x+351)*x+562)/(703/x+165)];
Phi[u_]=(1-Erf[u/Sqrt[2]])/2;
x=z/Sqrt[2];
p=.47047;a1=.3084284;a2=-.0849713;a3=.6627698;η=(1/(1+p x));F43[z_]=1/2(a1*η+a2*η^2+a3*η^3)*Erf'[x]//Simplify;
a1=.278393; a2=.230389; a3=.000972; a4=.078108;
F61[z_]=1/2/(1+a1 x+a2 x^2 + a3 x^3+a4 x^4)^4;
p=.381965;a1=.12771538;a2=.54107939;a3=-.53859539;a4=.75602755;η=(1/(1+p x));F44[z_]=1/2(a1*η+a2*η^2+a3*η^3+a4 η^4)*Erf'[x]//Simplify;
p=.3275911;a1=.225836846;a2=-.252128668;a3=1.259695130;a4=-1.287822453; a5=.940646070;η=(1/(1+p x));F45[z_]=1/2(a1*η+a2*η^2+a3*η^3+a4 η^4+a5 η^5)*Erf'[x]//Simplify;
Null

F45[{1,2}]//N

F61[z]

0.2667839458564817` 0.019527`  0.00034365389565666214`

zzz={.1,.5,1.0,1.5}
TableForm[
{zzz, F61[zzz],F43[zzz],F44[zzz],F45[zzz], Derenzo[zzz],Phi[zzz]//N}
]

{0.1`,0.5`,1.`,1.5`,2,(2/5),3,3.5`,4,4.5`}

Derenzo[11.8]

zzz={.1,.5,1.0,1.5}
zzz={2,3,5,7,9}
TableForm[
{zzz,  Derenzo[zzz]}
]

({{2, 3, 5, 7}, {0.022750316486526465`, 0.001349521387204997`, 2.8668696542520444`*^-7, 1.27306342558072`*^-12}})//TeXForm

zzz={10,13,15,20, 30, 40}
TableForm[
{zzz,  Phi[zzz]//N, Derenzo[zzz]//N}
]

{10,13,15,20, 30, 40}