A study by AIIMS, Gorakhpur, published in the International Journal of Mycobacteriology, indicates that smear microscopy, a common TB diagnostic test in India, misses a significant number of cases. The test detected TB in only 4.3% of samples, while the TrueNat test identified it in 13.7%. Researchers highlight that smear microscopy is less effective for patients with low bacterial load, early-stage disease, extra-pulmonary TB, or co-morbidities like HIV and diabetes, potentially delaying treatment and transmission.