Quality of medicines per API in the included prevalence surveys and equivalence studiesBecause of the limited number of samples tested for quality in the studies included in this review, the numbers should not be interpreted as representative of the prevalence of specific SF antidiabetics (please refer to the discussion section of the current paper for more details)
| API | Prevalence survey failure rate (n/N, %) | Equivalence study failure rate (n/N, %) | Total failure rate (n/N, %) |
| Glimepiride | 0/15 (0.0) | 13/23 (56.5) | 13/38 (34.2) |
| Sitagliptin | N/A | 2/5 (40.0) | 2/5 (40.0) |
| Voglibose | N/A | 1/5 (20.0) | 1/5 (20.0) |
| Metformin | 14/258 (5.4) | 18/89 (20.2) | 32/345 (9.3) |
| Glibenclamide | 22/239 (9.2) | 3/27 (11.1) | 25/266 (9.4) |
| Gliclazide | 0/15 (0.0) | N/A | 0/15 (0.0) |
| Total | 36/527 (6.8) | 37/147 (25.2) | 73/674 (10.8) |
No studies found for: meglitinide, chlorpropamide, tolbutamide, glipizide, repaglinide, vildagliptin, saxagliptin, pramlintide, empagliflozin, canagliflozin, dapagliflozin, dulaglutide, alogliptin, nateglinide, colesevelam, bromocriptine, albiglutide, lixisenatide, buformin, glibornuride, gliquidone, mitiglinide, miglitol, tolazamide.
API, active pharmaceutical ingredient; N/A, not applicable; SF, substandard and falsified.