Effectiveness and Implementation of A Clinical Risk Score for Early Diagnosis of Tuberculosis in Uganda: A Pragmatic, Clustered Randomization Clinical Trial.

Background Undertreatment of tuberculosis (TB) is common in resource-limited settings where same-day microbiological diagnosis is unavailable. We evaluated if a simple clinical risk score for predicting active TB could facilitate treatment initiation among individuals at high risk for TB. Methods We conducted a pragmatic, implementation-effectiveness study in peri-urban primary health clinics in Uganda. Four intervention clinics were paired with standard-of-care comparison clinics. Providers in intervention clinics were trained to use the score and set a threshold score for considering same-day treatment initiation; treatment decisions were at the providers' discretion. Our primary effectiveness outcome was the change in the proportion of individuals with confirmed TB who started on treatment within seven days of presentation, comparing pre-intervention and post-intervention periods. Results Among intervention clinics, 594/720 (83%) people diagnosed with TB started treatment within seven days during the pre-intervention period, versus 264/316 (84%) after implementation (pre-post difference 1%; 95% confidence interval [95%CI]: -6, 8%). In comparison clinics, seven-day treatment initiation changed from 312/363 (86%) pre-intervention to 153/211 (73%) post-intervention (pre-post difference -13%; 95%CI: -22, -5%). A difference-in-differences estimate was 14% (95%CI: 10, 19%). In intervention clinics, 1,206 of 1,826 (66%) people presenting with TB symptoms were administered the risk score. 229 (19%) had a score above the treatment threshold and 105 (46%) initiated treatment on the same day. Conclusions An easy-to-use clinical risk score did not increase seven-day empiric treatment initiation in intervention clinics. However, it improved rapid treatment initiation relative to clinics using the prevailing standard-of-care. The score was also highly acceptable to clinical providers. Clinical trial registration available at www.clinicaltrials.gov, ID: __NCT05122624 __________.