Fixed length ASCII data format. The data looks like this:
0013456
0023456
0033456
0043456
where 001, 002, 003, 004 are IDs, and 3,4,5,6 are item responses.
If you use SAS to prepare the data set, you can use,
data _NULL_;
set Have; * read the data to SAS;
file ' want.dat'; * the data you want;
put @1 ID @4 item1 @5 item2 @6 item3 @7item4;
run;
If you use SPSS to prepare the data, you can save data as fixed ASCII format. Let me know if you have further questions.