Table 3.
Study time period and study procedures.
| Visit | Time interval | Study procedures | Cumulative time period |
| 1 | Study start | Patients referred from peripheral sites Patients interviewed and informed consent obtained Tests to determine if subjects fulfil inclusion criteria Drug history and anthropometric measures Patients informed to attend next visit after one week for results and appropriate counselling |
0 |
| 2 | 2 weeks | Subjects fulfilling inclusion criteria will be invited to partake in the study Subjects not fulfilling the inclusion criteria will be counselled and directed back to initial referral center All subjects will be given dietary advice and a standard exercise protocol, and will be allowed access to the university gym Randomized to either metformin (500 mg daily) and placebo (daily) or metformin 500 mg daily and sitagliptin (25 mg daily) for one month |
2 weeks |
| 3 | 2 weeks | Efficacy and safety measures Dose escalation to metformin 1000 mg and sitagliptin 50 mg daily Subjects that have progressed to type 2 DM will be referred for management Lifestyle modification advice reenforced |
1 month |
| 4 | 1 month | Glycemic measures repeated Tests for safety (biochemical and clinical), anthropometric measures, lipid profiles, quality of life forms, safety data, FBI levels |
2 months |
| 5 | 2 months | Repeat | 4 months |
| 6 | 2 months | Repeat | 6 months |
| 7 | 2 months | Repeat | 8 months |
| 8 | 2 months | Repeat | 10 months |
| 9 | 2 months | Repeat | 1 year |
| 10 | 3 months | Repeat | 1 years and 3 months |
| 11 | 3 months | Repeat | 1 years and 6 months |
| 12 | 3 months | Repeat | 1 years and 9 months |
| 13 | 3 months | Repeat | 2 years |
| 14 | 3 months | Repeat | 2 years and 3 months |
| 15 | 3 months | Repeat | 2 years and 6 months |
| 16 | 3 months | Repeat | 2 years and 9 months |
| 17 | 3 months | Repeat | 3 years |
| 18 | 3 months | Repeat | 3 years and 3 months |
| 19 | 3 months | Repeat | 3 years and 6 months |
| 20 | 3 months | Repeat | 3 years and 9 months |
| 21 | 3 months | Repeat | 4 years |
| 22 | 3 months | Repeat | 4 years and 3 months |
| 23 | 3 months | Repeat | 4 years and 6 months |
| 24 | 3 months | Repeat and medication stopped | 4 years and 9 months |
| 25 | 3 months | Glycemic measures and safety tests Patients referred to appropriate clinics |
5 years |