They found a total of 59 patients. Fill in the attack rate per million[SL1] and the RR by characteristic – use the category of that characteristic marked with a * as the reference group (may differ from original paper) 

Characteristic #cases(%) NYC population attack rate** RR by per million pop. characteristic

Age(yr)

0–19 * 2 (3) 2,324,081 0.9 1.0

20–29 1 (2) 1,553,981 0.6 ____

30–39 3 (5) 1,549,111 1.9 ____

40–49 1 (2) 1,177,190 1.7 ____

50–59 9 (15) 867,331 10.4 ____

60–69 13 (22) 814,838 16.0 ____

70–79 18 (31) 534,785 33.7 ____

»80 12 (20) 281,054 42.7 49.615

Age category (yr)

»50 * 52 (88) 2,498,008 20.8 ____

<50 7 (12) 6,604,363 1.06 1.0

Sex

Male* 31 (53) 4,289,988 7.2 ____

Female 28 (47) 4,812,383 5.8 1.0

Race

White* 41 (69) 5,983,901 6.9 ____

Nonwhite 9 (15) 3,118,470 2.9 1.0

Unknown 9 (15) ------ n/a n/a

Borough or county of residence

New York City

Brooklyn (Kings) * 3 (5) 2,300,664 1.3 ___

Bronx 9 (15) 1,203,789 7.5 ____

Manhattan 1 (2) 1,487,536 0.7 ____

Queens 32 (54)§ 1,951,599 16.4 ____

Staten Island 0 379,999 0 ____

New York State

(just outside the city) 14 2,162,214 we will ignore this risk group for this exercise

*Population figures are from the 1990 U.S. Census. †CI denotes confidence interval. . §This group includes a Canadian tourist who became ill after visiting relatives in Queens

Actually, the authors called it “rate of infection” in this column but still attack rates in the heading. That is somewhat misleading since the data has no unit of time (not a rate) and this only counts cases- not actual infections. These are accepted limitations of what is generally called “attack rate” in an investigation

Calculate the overall attack rate [SL2] (1 pt.) 

Describe 2 of the patterns you can see from this data. (2pts)