WP op-ed: Service in Iraq: Just How Risky?

[DeepModem Mom]

Service in Iraq: Just How Risky?
By Samuel H. Preston and Emily Buzzell
Saturday, August 26, 2006; Page A21

The consequences of Operation Iraqi Freedom for U.S. forces are being documented by the Defense Department with an exceptional degree of openness and transparency. Its daily and cumulative counts of deaths receive a great deal of publicity. But deaths alone don't indicate the risk for an individual. For this purpose, the number of deaths must be compared with the number of individuals exposed to the risk of death. The Defense Department has supplied us with appropriate data on exposure, and we take advantage of it to provide the first profile of military mortality in Iraq.

Between March 21, 2003, when the first military death was recorded in Iraq, and March 31, 2006, there were 2,321 deaths among American troops in Iraq. Seventy-nine percent were a result of action by hostile forces. Troops spent a total of 592,002 "person-years" in Iraq during this period. The ratio of deaths to person-years, .00392, or 3.92 deaths per 1,000 person-years, is the death rate of military personnel in Iraq....

***

The death rate of American troops in Vietnam was 5.6 times that observed in Iraq. Part of the reduction in the death rate is attributable to improvements in military medicine and such things as the use of body armor. These have reduced the ratio of deaths to wounds from 24 percent in Vietnam to 13 percent in Iraq....Marines are paying the highest toll in Iraq. Their death rate is more than double that of the Army, 10 times higher than that of the Navy and 20 times higher than for the Air Force.... In both the Army and the Marines, enlisted personnel have 40 percent higher mortality than officers. The excess mortality of enlisted soldiers is diminished by the high mortality of the lowest-ranking officers, lieutenants, who are typically the leaders of combat patrols. Lieutenants have the highest mortality of any rank in the Army, 19 percent higher than all Army troops combined. Marine Corps lieutenants have 11 percent higher mortality than all Marines. But the single highest-mortality group in any service consists of lance corporals in the Marines, whose death risk is 3.3 times that of all troops in Iraq....

***

In contrast to the civilian population, mortality rates decline precipitously with age. Troops ages 17 to 19 have a death risk 4.6 times that of those 50 and older. Differences in rank by age undoubtedly contribute to this pattern, and so do differences in branch of service....The number of wounded in Iraq through March 31, 2006, was 7.5 times the number of dead; the rate at which wounds are incurred was one per 33 troops per year. We do not have the same information about the characteristics of those wounded as we have about those killed....

(Samuel H. Preston is the Frederick J. Warren professor of demography at the University of Pennsylvania. Emily Buzzell is a student in the Health and Societies Program at Penn.)

http://www.washingtonpost.com/wp-dyn/content/article/2006/08/25/AR2006082500940.html?nav%3Dmost_emailed&sub=AR

[lostnfound]

1. So death rate is 156% higher than same age group in US, and 669% for lance

corporals..

"The death rate for U.S. men ages 18 to 39 in 2003 was 1.53 per 1,000 -- 39 percent of that of troops in Iraq." 1/.39 = 2.56; 2.56 - 1 = 156%

And for lance corporals, death rate is 3 x higher than all troops.. 3.92 x 3 = 11.76.. 11.76 / 1.53 = 7.69 => 669% higher.

[HereSince1628]

2. But then in Vietnam most people only did one tour.

There are soldiers in Iraq on their 3rd tours. Isn't their overall risk calculated as 3X the risk during one tour?

[Bucky]

3. Not if the demographer knows what he's doing.

That's not risk of death on a per-day basis. That wouldn't make much sense from an analytical point of view. mortality stats need to be based on annual death rates, since daily death counts can fluctuate so much.

[HereSince1628]

4. I don't understand why you are bringing up daily risk

The figures seem to be for a period of one year.

If you consider a batter a baseball. They have a batting average that can be expressed as a probability based on the historic lieklihood they will get a hit during any at bat. Assuming the batting average is constant, if a player batting .200 average gets to bat 100 times we expect about 20 hits.