LIBNAME lib 'path to your libary'; DATA one; SET lib.gababies; RUN; DATA one; SET one; IF INITAGE le 20 then agebin = 1; ELSE IF INITAGE gt 20 then agebin = 0; RUN; ODS PDF; TITLE 'Clustered Data Analysis using Mixed Model'; PROC MIXED DATA=one; CLASS momid agebin; MODEL BWEIGHT = agebin/ S ; RANDOM INT / SUBJECT=momid VCORR; LSMEANS agebin; RUN; ODS PDF CLOSE;