Dear all,

I'm doing a scatter plot (potassium levels in 2 distinct moments) with this code (which works fine):

twoway (lfitci Pre_Pot Post_Pot, ciplot(rarea)) (scatter Pre_Pot Post_Pot,c(. l) m(Oh) mc(black) msiz(small)) (line W W, lp(dash) lc(black)) if Sequence==0, ytitle(Potassium(mEq/L)) xtitle(Potassium(mEq/L)) legend(order(1 2)) legend(off) text(7.8 7 "Line 45°",size(vsmall) place(e)) text(5.1 6.8 "Lfit: y=2.10 +0.52x",size(vsmall) place(e)) text(4.9 7 "{&sigma}{superscript:2}=0.43",size(vsmall) place(e)) xlab(2(1)8) ylab(2(1)8) xmtick(##10) ymtick(##10) ysize(5.5) graphregion(fcolor(white))

and produce this graph:

Array

The dashed line (45°) was created just to add a reference to the reader using:
generate W=_n
replace W=. if W>8 | W<1.4

My problem is when I try do to the same graph for the group Sequence=1. Changing the conditional from 0 to 1 the dashed line disappears!

twoway (lfitci Pre_Pot Post_Pot, ciplot(rarea))(scatter Pre_Pot Post_Pot,c(. l) m(Oh) mc(black) msiz(small)) (line W W, lp(dash) lc(black)) if Sequence==1, ytitle(Potassium(mEq/L)) xtitle(Potassium(mEq/L)) legend(order(1 2)) legend(off) text(7.8 7 "Line 45°",size(vsmall) place(e)) text(5.1 6.8 "Lfit: y=2.35 +0.48x",size(vsmall) place(e)) text(4.9 7 "{&sigma}{superscript:2}=0.59",size(vsmall) place(e)) xlab(2(1)8) ylab(2(1)8) xmtick(##10) ymtick(##10) ysize(5.5) graphregion(fcolor(white))

Array

ps: Sequence is a binary variable where 0 the patient started in one dialysis modality (CAPD) whilst 1 the patient started in another dialysis modality (APD)

Regards

Thyago