d STB-45 sg90. Akaike's information criterion and Schwarz's criterion. d STB insert by d Aurelio Tobias, Institut Municipal d'Investigacio Medica, d (IMIM), Barcelona; d Michael J. Campbell, University of Sheffield, UK. d Support: atobias@@imim.es and m.j.campbell@@sheffield.ac.uk d After installation, see help ^mlfit^. f sg90/mlfit.ado f sg90/mlfit.hlp f sg90/birthwt.dta