TY - JOUR
T1 - Accuracy of computer-aided chest X-ray in community-based tuberculosis screening: Lessons from the 2016 Kenya National Tuberculosis Prevalence Survey
AU - Mungai, Brenda
AU - Ong‘angò, Jane
AU - Ku, Chu Chang
AU - Henrion, Marc
AU - Morton, Benjamin
AU - Joekes, Elizabeth
AU - Onyango, Elizabeth
AU - Kiplimo, Richard
AU - Kirathe, Dickson
AU - Masini, Enos
AU - Sitienei, Joseph
AU - Manduku, Veronica
AU - Mugi, Beatrice
AU - Squire, Bertie
AU - MacPherson, Peter
AU - Addo-Yobo, Emmanuel
AU - Allwood, Brian
AU - Banda, Hastings
AU - Bates, Imelda
AU - Binegdie, Amsalu
AU - Chakaya, Muhwa Jeremiah
AU - El Sony, Asma
AU - Falade, Adegoke
AU - Khan, Jahangir
AU - Lesosky, Maia
AU - Mbatchou, Bertrand
AU - Meme, Hellen
AU - Mortimer, Kevin
AU - Mutayoba, Beatrice
AU - Niessen, Louis
AU - Ntinginya, Nyanda Elias
AU - Obasi, Angela
AU - Rylance, Jamie
AU - Taegtmeyer, Miriam
AU - Tolhurst, Rachel
AU - Worodria, William
AU - Zar, Heather
AU - Zulu, Eliya
AU - Zurba, Lindsay
PY - 2022/11/23
Y1 - 2022/11/23
N2 - Community-based screening for tuberculosis (TB) could improve detection but is resource intensive. We set out to evaluate the accuracy of computer-aided TB screening using digital chest X-ray (CXR) to determine if this approach met target product profiles (TPP) for community-based screening. CXR images from participants in the 2016 Kenya National TB Prevalence Survey were evaluated using CAD4TBv6 (Delft Imaging), giving a probabilistic score for pulmonary TB ranging from 0 (low probability) to 99 (high probability). We constructed a Bayesian latent class model to estimate the accuracy of CAD4TBv6 screening compared to bacteriologically-confirmed TB across CAD4TBv6 threshold cut-offs, incorporating data on Clinical Officer CXR interpretation, participant demographics (age, sex, TB symptoms, previous TB history), and sputum results. We compared model-estimated sensitivity and specificity of CAD4TBv6 to optimum and minimum TPPs. Of 63,050 prevalence survey participants, 61,848 (98%) had analysable CXR images, and 8,966 (14.5%) underwent sputum bacteriological testing; 298 had bacteriologically-confirmed pulmonary TB. Median CAD4TBv6 scores for participants with bacteriologically-confirmed TB were significantly higher (72, IQR: 58–82.75) compared to participants with bacteriologically-negative sputum results (49, IQR: 44–57, p<0.0001). CAD4TBv6 met the optimum TPP; with the threshold set to achieve a mean sensitivity of 95% (optimum TPP), specificity was 83.3%, (95% credible interval [CrI]: 83.0%—83.7%, CAD4TBv6 threshold: 55). There was considerable variation in accuracy by participant characteristics, with older individuals and those with previous TB having lowest specificity. CAD4TBv6 met the optimal TPP for TB community screening. To optimise screening accuracy and efficiency of confirmatory sputum testing, we recommend that an adaptive approach to threshold setting is adopted based on participant characteristics.
AB - Community-based screening for tuberculosis (TB) could improve detection but is resource intensive. We set out to evaluate the accuracy of computer-aided TB screening using digital chest X-ray (CXR) to determine if this approach met target product profiles (TPP) for community-based screening. CXR images from participants in the 2016 Kenya National TB Prevalence Survey were evaluated using CAD4TBv6 (Delft Imaging), giving a probabilistic score for pulmonary TB ranging from 0 (low probability) to 99 (high probability). We constructed a Bayesian latent class model to estimate the accuracy of CAD4TBv6 screening compared to bacteriologically-confirmed TB across CAD4TBv6 threshold cut-offs, incorporating data on Clinical Officer CXR interpretation, participant demographics (age, sex, TB symptoms, previous TB history), and sputum results. We compared model-estimated sensitivity and specificity of CAD4TBv6 to optimum and minimum TPPs. Of 63,050 prevalence survey participants, 61,848 (98%) had analysable CXR images, and 8,966 (14.5%) underwent sputum bacteriological testing; 298 had bacteriologically-confirmed pulmonary TB. Median CAD4TBv6 scores for participants with bacteriologically-confirmed TB were significantly higher (72, IQR: 58–82.75) compared to participants with bacteriologically-negative sputum results (49, IQR: 44–57, p<0.0001). CAD4TBv6 met the optimum TPP; with the threshold set to achieve a mean sensitivity of 95% (optimum TPP), specificity was 83.3%, (95% credible interval [CrI]: 83.0%—83.7%, CAD4TBv6 threshold: 55). There was considerable variation in accuracy by participant characteristics, with older individuals and those with previous TB having lowest specificity. CAD4TBv6 met the optimal TPP for TB community screening. To optimise screening accuracy and efficiency of confirmatory sputum testing, we recommend that an adaptive approach to threshold setting is adopted based on participant characteristics.
U2 - 10.1371/journal.pgph.0001272
DO - 10.1371/journal.pgph.0001272
M3 - Article
SN - 2767-3375
VL - 2
SP - e0001272
JO - PLOS Global Public Health
JF - PLOS Global Public Health
IS - 11
M1 - e0001272
ER -
