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# Understanding the TB Cohort Review Process: Instruction Guide (2006)

#### Appendix A: Answers to Exercises

##### Answers to Exercise 6Calculation of Indices/Rates for Treatment of TB Disease

1. Index of treatment completion:

 a x 100 = 26 = 26 = .65 x 100 = 65% Total cases – (c + d + e) 43 – (1+2+0) 40

2. Index of possible treatment completion:

 a x 100 = 26 = 26 = .703 x 100 = 70.3% Total cases – (c + d + e + f + g + h) 43 – (1+2+0+1+0+2) 37

3. Index of likely to complete treatment:

 a + b x 100 = 26+ 8 = 34 = .919 x 100 = 91.9% Total cases – (c + d + e + f + g + h) 43 – (1+2+0+1+0+2) 37

4. Death rate:

 d + h x 100 = 2 +2 = 4 = .095 x 100 = 9.5% Total cases – (c + e) 43 – (1+0) 42

5. Default rate:

 k x 100 = 1 = 1 = .024 x 100 = 2.4% Total cases – (c + e) 43 – (1+0) 42

6. Cohort failure rate:

 i + k x 100 = 1+ 1 = 2 = .048 x 100 = 4.8% Total cases – (c + e) 43 – (1+0) 42

##### Answers to Exercise 7Calculation of Indices for Contact Investigation

1. Cohort failure rate:

 # of contacts identified = 294 = 7 # of pulmonary cases 42

2. Percent smear positive cases with >0 contacts identified:

 # smear positive cases with # identified >0 = 19 = .95 x 100 = 95% # smear positive cases 20

3. Percent contacts of smear positive cases evaluated:

 # contacts of smear positive cases evaluated = 182 = .90 x 100 = 90.1% # contacts of smear positive cases 202

4. Percent contacts of smear positive cases completing treatment for LTBI:

 # contacts of smear positive cases comp. trtmt for LTBI = 10 = .217 x 100 = 21.7% # contacts of smear positive cases started trtmt for LTBI 46

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