Patients included in the stratified analyses by medication
| Stratified analysis | Studies included | Cases | Controls | Total |
|---|---|---|---|---|
| Sulfasalazine vs non-IBD controls | 12 | 702 | 1966 | 2668 |
| Mesalazine vs non-IBD controls | 8 | 557 | 1044 | 1601 |
| Corticosteroids vs non-IBD controls | 5 | 268 | 1177 | 1445 |
| Antibiotics vs non-IBD controls | 5 | 117 | 886 | 1003 |
| NOSASP patients with IBD vs non-IBD controls | 10 | 487 | 2774 | 3261 |
| NOSASP patients with IBD vs SASP patients with IBD | 7 | 408 | 190* | 598 |
| NOMED patients with IBD vs non-IBD controls | 4 | 103 | 215 | 318 |
NOMED, patients with IBD not using medications at all;. NOSASP, patients with IBD not using sulfasalazine but with unclear previous or current use of other medications; SASP, patients with IBD using sulfasalazine.
*Corresponds to SASP patients with IBD.