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Table 2 Base case scenario parameters. Selected parameters for cost-effectiveness of California tuberculosis B-notifications. Full details and additional parameters are given in the Appendix [see Additional file 1]. Note 1: California TB surveillance for individuals from major countries of origin, 2002. Note 2: one minus the relative risk of disease given completion of LTBI therapy relative to no therapy, assuming isoniazid-sensitive infection. Note 3: assuming no false positives due to prior BCG vaccination. Note 4: rate per 100 000 person-years. See Appendix [Additional file 1] for further details and complete references.

From: Cost-effectiveness of tuberculosis evaluation and treatment of newly-arrived immigrants

Description Values
Mean age (Note 1) 53.3
INH resistance 0.129
Drug-induced hepatitis rates 0.0008 to 0.0028
Efficacy of completed regimen (Note 2) 70%
Mean time to passive diagnosis 74 days
TST sensitivity 93%
TST specificity (Note 3) 99%
Probability of fast progression to TB after infection 0.05
Probability of finding a TB contact 80%
Fraction of individuals with B-notification  
   with active disease 3%
   in class TB4 60%
   in class TB2 22%
Fraction of  
   baseline active cases smear positive 7.5%
   TB4s eligible for LTBI therapy 63%
Hospitalization probability  
   actively detected smear-positive 0.35
   actively detected smear-negative 0.081
   passively detected smear-positive 0.66
   passively detected smear-negative 0.51
Transmission (new infections per year)  
   smear-positive source case 8
   smear-negative source case 0.8
Attrition cascade for domestic follow-up after B-notification  
   Evaluation rate 60%
   Starting rate, LTBI therapy 80%
   Completion rate, LTBI therapy 75%
Reactivation rate at baseline, Note 4  
   class TB4 600
   class TB2 217