| Data file | Cases | Variables | 
|---|---|---|
| INT_COG12_DEC03 Cognitive item response data file. | 386729 | 264 | 
| INT_COG12_S_DEC03 Scored cognitive item response data file. | 485490 | 216 | 
| INT_PAQ12_DEC03 Parent questionnaire data file. | 102032 | 143 | 
| INT_SCQ12_DEC03 School questionnaire data file. | 18139 | 291 | 
| INT_STU12_DEC03 Student questionnaire data file. | 485490 | 634 |