st: Plotting several linear associations in one graph for comparison

[Amal Khanolkar <Amal.Khanolkar@ki.se>]

Hi all,

- I've run some very basic and simple linear regression models to analyse associations between standardized birth weight and blood pressure, adjusting for confounders like birth year, current age, BMI, height etc. 

- The associations between birth weight and blood pressure are stratified by ethnicity (12 ethnic goups - thus 12 separate linear regression models). I see that the association between birth weight and blood pressure does differ in the various ethnic goups.

- I would now like to plot the above associations in a single graph using different colours for the various ethnic groups for comparison.

Any ideas how this can be done appropriately?  

I have previously used the kdensity and twoway commands to plot BW distributions by ethnic groups as follows:

kdensity bw if motherland==1 , generate(x_sweden y_sweden)
kdensity bw if motherland==5 , generate(x_poland y_poland)
kdensity bw if motherland==7 , generate(x_arab y_arab)
kdensity bw if motherland==8 , generate(x_iraq y_iraq)

twoway (line y_sweden x_sweden, sort) ///
       (line y_poland x_poland, sort) ///
       (line y_arab x_arab, sort) ///
	   (line y_iraq x_iraq, sort) ///

legend(order(1 "Sweden" 5 "Poland" 7 "Arab" 8 "Iraq")) 


Can the above twoway command be manipulated for my current need? Or any other suggestions? 

Thanks & regards,


Amal Khanolkar.


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