Another hint for copy paste from spreadsheet as indicated by Hans and Jamie is that sometimes one has a spreadsheet like this (simplified):
visit exposed sex problems surgery 01-01-1990 1 1 1 10-01-2000 01-11-1991 0 1 1 10-01-2000 01-11-1992 0 1 0 01-12-1993 1 1 1 10-01-2000
to read this with copy paste you just add one column on the right to get a "full" square
visit exposed sex problems surgery x 01-01-1990 1 1 1 10-01-2000 x 01-11-1991 0 1 1 10-01-2000 x 01-11-1992 0 1 0 x 01-12-1993 1 1 1 10-01-2000 x
after reading into analysis with "read /cb" you just drop the variable x
Jens Lauritsen EpiData Association