why not using something like this based on a surveymeans (adapted to NHANES)? Here also, you can code as 1/0 or 100/0 your categories to have the prevalence and keep the original metric for continuous (to have age adjusted estimates for continuous)
proc surveymeans data=/*dataset name*/;
STRATA sdmvstra;
CLUSTER sdmvpsu;
CLASS age_c; /*your age class variable (10 years age class)*/
WEIGHT WTINT2YR;
var X; /*the variable you want to have (continuous or 1/0 or 1/100 for prevalence)*/
run;
I add a little piece. I feel awkward with the regression procedure because you should have something like...
here the numbers 0.0696 0.0747 0.1329 0.2408 0.2855 0.1965 are the coefficients of my estimate statement (here I have my relative frequencies) ok if I use this reg I obtain 38.3% but using the observed frequencies is not very rigorous
if I use age classes frequencies estimated using a survey freq then I have other coefficients and my procedure became