Table 1

Observed and expected tuberculosis case counts by select demographic and risk factor characteristics for January-December 2009, United States

Observed Case Count

Expected Case Count

(95% Prediction Interval)

Case Count Difference*

Percentage of

Expected

P value


Total

11545

12539 (12233 - 12853)

-994

-7.9

<.001


Country of origin


Foreign-born

6854

7709 (7318 - 8120)

-855

-11.1

<.001


U.S.-born

4571

4918 (4661 - 5190)

-347

-7.1

.005


Unknown

120

21 (10 - 48)

99

471.4

.020


For foreign-born, length of stay in United States


< 2 years

1432

1872 (1590 - 2204)

-440

-23.5

<.001


> = 2 years

4712

5197 (4865 - 5551)

-485

-9.3

.001


Unknown

710

684 (599 - 781)

26

3.8

.587


For foreign-born, country of origin

according to implementation of 2007

immigration technical instructions (TI)


TI countries

2993

3384 (3095 - 3699)

-391

-11.6

.002


Non-TI countries

3861

4325 (4044 - 4625)

-464

-10.7

<.001


Race/ethnicity


Hispanic

3380

3953 (3563 - 4385)

-573

-14.5

<.001


Non-Hispanic

American Indian

102

121 (100 - 148)

-19

-15.7

.151


Non-Hispanic

Asian

3192

3355 (3093 - 3639)

-163

-4.9

.186


Non-Hispanic

Black

2868

3135 (2963 - 3317)

-267

-8.5

.002


Non-Hispanic

Native Hawaiian

75

75 (43 - 130)

0

0.0

1.00


Non-Hispanic

White

1829

1954 (1812 - 2108)

-125

-6.4

.085


Non-Hispanic

Multiple/Unknown

99

55 (32 - 95)

44

80.0

.080


Age at TB diagnosis in years


0-4

401

464 (405 - 532)

-63

-13.6

.040


5-14

245

292 (241 - 352)

-47

-16.1

.061


15-24

1274

1494 (1360 - 1641)

-220

-14.7

<.001


25-44

3893

4098 (3897 - 4309)

-205

-5.0

.048


45-64

3434

3846 (3624 - 4082)

-412

-10.7

<.001


65+

2292

2358 (2240 - 2482)

-66

-2.8

.339


Unknown

6

1 (1 - 1)

5

500.0

.041


Disease location


Pulmonary only

7976

8751 (8436 - 9078)

-775

-8.9

<.001


Extrapulmonary only

2383

2594 (2465 - 2730)

-211

-8.1

.003


Both

1028

1169 (1031 - 1326)

-141

-12.1

.026


Unknown

158

27 (3 - 211)

131

485.2

.344


Case verification


Positive culture

8876

9706 (9423 - 9997)

-830

-8.6

<.001


Positive NAA†

57

--

--

--


Positive smear

91

63 (45 - 89)

28

44.4

.084


Clinical case

1630

1426 (1243 - 1637)

204

14.3

.048


Provider diagnosis

891

1364 (1246 - 1492)

-473

-34.7

<.001


Homeless in the year

prior to TB diagnosis


Yes

571

695 (623 - 774)

-124

-17.8

<.001


No

10797

11833 (11540 - 12133)

-1036

-8.8

<.001


Unknown

177

57 (22 - 147)

120

210.5

.094


Resident of a correctional facility at time of TB diagnosis


Yes

461

480 (389 - 593)

-19

-4.0

.682


No

11041

12055 (11796 - 12319)

-1014

-8.4

<.001


Unknown

43

7 (2 - 29)

36

514.3

.189


Excess alcohol use in the year prior to TB diagnosis


Yes

1382

1528 (1414 - 1652)

-146

-9.6

.013


No

9877

10889 (10641 - 11144)

-1012

-9.3

<.001


Unknown

286

180 (129 - 251)

106

58.9

.016


Injecting drug use in the year prior to TB diagnosis


Yes

152

216 (182 - 256)

-64

-29.6

<.001


No

11087

12165 (11831 - 12510)

-1078

-8.9

<.001


Unknown

306

203 (129 - 320)

103

50.7

.093


Non-injecting drug use in the year prior to TB diagnosis


Yes

828

922 (829 - 1026)

-94

-10.2

.046


No

10391

11438 (11178 - 11703)

-1047

-9.2

<.001


Unknown

326

221 (137 - 355)

105

47.5

.122


HIV status at time of TB diagnosis


Positive

706

797 (748 - 849)

-91

-11.4

.005


Negative

6337

7621 (7171 - 8100)

-1284

-16.8

<.001


Unknown

4502

4347 (4134 - 4572)

155

3.6

.185


Software for TB reporting


TIMS

4455

4775 (4552 - 5009)

-320

-6.7

.004


Other

7090

7771 (7470 - 8084)

-681

-8.8

<.001


*Expected case counts are derived from ratios (i.e., regression slopes on log-transformed observed counts). Because the sum of ratios is not the ratio of the sums, expected case counts stratified on case characteristics do not sum to overall case counts. All stratified count differences sum to within the 95% prediction interval (-688 to -1308) for the overall case count difference (-994).

† NAA = nucleic acid amplification test, which was not recorded as a TB case verification criteria until 2009, thus there are no comparable data from which to calculate expected values. In 2009, clinical cases include TB verified by positive interferon gamma release assay (IGRA) in lieu of tuberculin skin test, or by abnormal chest computerized tomography (CT) scan in lieu of chest radiograph; previously, such cases were verified by provider diagnosis because the National Tuberculosis Surveillance System did not collect IGRA or CT scan results prior to 2009.

‡TIMS = Tuberculosis Information Management System in operation since 1998. Other = National Electronic Disease Surveillance System-compliant software newly introduced in 2009.

Winston et al. BMC Public Health 2011 11:846   doi:10.1186/1471-2458-11-846

Open Data