Table 3. Additional Yield of new cases of Diabetes Mellitus and Number Needed to Screen to diagnose a new case of DM among tuberculosis patients in the state of Kerala, India, June–July 2011.
| Characteristic | Number of TB patients whose DM status was ascertained [a] | Number with previously known DM [b] | Number of DM newly diagnosed [c] | Additional Yield [c/(b+c)*100] | Number needed to screen (NNS) [(a−b)/c] |
| Total | 552 | 128 | 115 | 47% | 3.7 |
| Sex | |||||
| Male | 420 | 108 | 100 | 48% | 3.1 |
| Female | 132 | 20 | 15 | 43% | 7.5 |
| Age (years) | |||||
| 15–24 | 57 | 3 | 1 | 25% | 52.6 |
| 25–34 | 70 | 4 | 11 | 73% | 6.0 |
| 35–44 | 114 | 19 | 25 | 57% | 3.8 |
| 45–54 | 134 | 44 | 30 | 41% | 3.0 |
| 55–64 | 106 | 38 | 29 | 43% | 2.3 |
| ≥65 | 71 | 20 | 19 | 49% | 2.6 |
| Residence | |||||
| Urban | 107 | 37 | 14 | 27% | 5.0 |
| Rural | 445 | 91 | 101 | 53% | 3.5 |
| Type of TB | |||||
| New Smear Positive Pulmonary TB | 307 | 87 | 70 | 45% | 3.1 |
| New Smear Negative Pulmonary TB | 37 | 4 | 7 | 64% | 4.7 |
| New Extra-pulmonary TB | 128 | 15 | 21 | 58% | 5.3 |
| Relapse | 35 | 12 | 8 | 40% | 3.3 |
| Treatment after Failure | 19 | 7 | 2 | 22% | 6.0 |
| Treatment after Default | 26 | 3 | 7 | 70% | 3.3 |
TB-Tuberculosis; DM- Diabetes Mellitus; NNS-Number needed to screen is defined as the reciprocal of the prevalence of newly diagnosed DM after excluding self-reported previously known cases of DM.