Table 4. Differences in LTBI diagnosis among referrals to BCHD between study periods and by QFT-GIT test status.
| Group | QFT-GIT category | Referral N | Evaluated by BCHD N (%) | Diagnosed LTBI N (%) | Initiation of treatment N (%)** | Completion of treatment† |
| Pre-QFT-GIT | Total | 607 | 452 (75%) | 445 (98%)° | 341 (77%) | 251 (74%) |
| QFT-GIT performed | 3 (1%)* | 3 (100%)°° | 2 (66%) | 2(100%) | ||
| • QFT-GIT negative | • – | • – | • – | • – | ||
| • QFT-GIT positive | • 3 (100%) | • 3 (100%) | • 2 (66%) | • 2 (100%) | ||
| No QFT-GIT performed | 449 (99%) | 442 (98%)°° | 339 (77%) | 249(78%) | ||
| Post-QFT-GIT | Total | 750 | 567 (76%) | 397(70%)° | 307 (77%) | 174/244 (75%) |
| QFT-GIT performed | 399 (70%)* | 230 (58%)°° | 174 (76%) | 105/137(77%) | ||
| • QFT-GIT negative | • 178 (45%) | • 10 (6%) | • 10(100%) | • 4/7(57%) | ||
| • QFT-GIT positive | • 209 (52%) | • 209 (100%) | • 157(75%) | • 97/120(81%) | ||
| No QFT-GIT performed | 168 (30%) | 167 (99%)°° | 133 (80%) | 69/107(65%) |
includes individuals that had QFT-GIT performed by referral source. 11/399 individuals in the post-QFT-GIT period had QFT-GIT drawn but no results available; there was 1 indeterminate result in the post-QFT-GIT-period.
°p<.001 comparing final diagnosis of LTBI between pre-QFT-GIT and post-QFT-GIT periods.
°°p = .827 for pre-QFT-GIT period comparing LTBI diagnosis between those with and without a QFT-GIT result; p<.001 in post-QFT-GIT period comparing LTBI diagnosis between those with and without QFT-GIT performed.
p = .81 comparing treatment initiation among those diagnosed with LTBI between pre-QFT-GIT and post-QFT-GIT periods; p = 0.690 comparing treatment initiation between those with and without QFT-GIT performed in the pre-QFT-GIT period; p = .349 comparing treatment intiation between those with and without QFT-GIT performed in the post-QFT-GIT period.
Analysis restricted to those who started an INH X 9 months regimen prior to Nov 30, 2010 or Rifampin X 4 months prior to March 30, 2011 to allow time for completion. p = .606 comparing overall treatment completion between pre-QFT-GIT period and post-QFT-GIT period. p = 0.101 comparing those with and without QFT-GIT performed in the post-QFT-GIT period; p = 0.70 comparing those with and without QFT-GIT in the pre-QFT-GIT period.