Hi, I'm helping a friend's daughter on a high school research project that aims to examine academic performance (i.e., mean test scores and overall class % attendance rate) across different school start times, adjusting for socioeconomic status (SES).  The data is grouped by grade level and school, so I do not have individual level data.  I do, however, have a breakdown of scores & % attendance broken down by SES (disadvantaged vs. not disadvantaged), as well as the number of students in each group/subgroup. My dependent (outcome) variables that I wish to compare are:  --mean reading test scores for a grade level & school  (and # of students in that grade level & school) --mean reading test scores for a grade level, school and SES  (and # of students in that grade level, school and SES stratum) --mean math test scores for a grade level & school  (and # of students in that grade level & school) --mean math test scores for a grade level, school and SES  (and # of students in that grade level, school and SES stratum) --% attendance rate for a grade level & school (and # of students in that grade level & school) --% attendance rate for a grade level, school, and SES (and # of students in that grade level, school and SES stratum) I cannot adjust by race/ethnicity or gender, since I don't have individual level data.   Would this be analyzed using ANOVA or a linear (or Poisson for the attendance rate?) regression analysis?  Or neither of these? If ANOVA or regression, how would I write the SAS code to take into account the grouping of data and number of students in each group?   Thanks for any help you can provide, --Laura ... View more