National Academies Press: OpenBook
« Previous: 5 Morbidity Results
Suggested Citation:"6 Discussion." National Academies of Sciences, Engineering, and Medicine. 2016. Assessing Health Outcomes Among Veterans of Project SHAD (Shipboard Hazard and Defense). Washington, DC: The National Academies Press. doi: 10.17226/21846.
×

6

Discussion

During the 1960s, nearly 5,900 members of the armed forces were present during the Shipboard Hazard and Defense tests—Project SHAD—that were conducted to assess vulnerabilities to and defenses against chemical and biological warfare at sea. The analysis described in this report was carried out to assess whether these men have been at increased risk for adverse health outcomes because of their participation in Project SHAD. This chapter provides a summary and interpretation of the findings of the analysis of the second Institute of Medicine (IOM) review of health outcomes among SHAD veterans, and describes its strengths and weaknesses for answering the questions posed.

FINDINGS ON MORTALITY

The committee examined the mortality data for the study population using three approaches: (1) The entire Project SHAD participant population was compared to the total population that served on comparison vessels and in comparison air and ground units. (2) Exposure-specific comparisons were made between SHAD participants and comparison groups to test hypotheses suggested by the scientific literature regarding health risks. (3) Additional exploratory analyses were carried out for groups established based upon the substance(s) used in the tests in which they participated, or the particular combination of substances to which they were exposed. The rationale for these groupings is described in Chapter 3.

The committee carried out multiple statistical tests in its examination of mortality differences in the groups described. Testing a large number of exposure-outcome associations increases the chance of reporting spurious associations. As a final step in the interpretation of its results, the committee applied statistical adjustments to account for the multiple comparisons in its analysis.

Overall Mortality

The Project SHAD participants and the comparison group were similar in terms of age, race where known, and proportions who were officers or enlisted personnel (see Table 4-1). Their survival experience was also similar, with no statistically significant difference in all-cause

Suggested Citation:"6 Discussion." National Academies of Sciences, Engineering, and Medicine. 2016. Assessing Health Outcomes Among Veterans of Project SHAD (Shipboard Hazard and Defense). Washington, DC: The National Academies Press. doi: 10.17226/21846.
×

mortality (see Table 4-3). No statistically significant increases in hazard for Project SHAD participants were seen when cause-specific mortality was examined.

Hypotheses Regarding Specific Exposures and Causes of Death

The committee paid particular attention to those Project SHAD test veterans who had been in tests that included the use of Coxiella burnetii, betapropiolactone (BPL), Escherichia coli (E. coli), sarin, or zinc cadmium sulfide because its review of the scientific literature (described in Appendix C) suggested the possibility that people exposed to these substances might be at increased risk for specific adverse health effects.1 The analysis of these hypotheses examined both all-cause mortality in the groups exposed to these substances and mortality from specific causes.

There were no significant differences between the exposed and comparison groups for all-cause mortality, either for the groups as a whole, or when officers and enlisted personnel were examined separately. In examining cause-specific mortality, the committee found no deaths attributed to most of the hypothesized health effects among either the participant or comparison groups (see Table 4-7). Deaths from cancer in general and lung cancer in particular could be analyzed in more detail. The hazard ratio for mortality from cancer was not statistically different in those exposed to BPL compared to the appropriate comparison units. The SHAD veterans who were exposed to zinc cadmium sulfide had a slight excess in lung cancer deaths that did not reach statistical significance (see Table 4-8). For both BPL and zinc cadmium sulfide exposure groups, no difference was found between the SHAD veterans and the comparison groups when the enlisted group was examined separately.

The committee also examined the effect of the number of opportunities for exposure to these substances. No association with increasing mortality from cancer was observed in those with more potential exposure to BPL or zinc cadmium sulfide (see Table 4-9).

Exploratory Analyses of Mortality

The committee sought to be particularly thorough in its analyses and open to the potential for findings that were not suggested by its review of the literature. The SHAD tests involved multiple experiences which could for some participants have included aspects not captured by the reports from the Department of Defense (DoD) of substances used in the tests. The committee therefore also examined mortality in six additional groups. These groupings were defined as (1) exposure to any biological test substance; (2) exposure to any chemical test substance (except trioctyl phosphate [TOF]); (3) exposure to any decontaminant; (4) exposure to TOF, which was used only in Test 69-10; (5) service on the light tugs or as Project SHAD staff on the USS Granville S. Hall, and (6) service on the USS George Eastman.

There were no overall differences in survival when the six groups were compared with their respective comparison groups, or when stratified by rank (officer or enlisted) (see Table 4-11). No association with increasing mortality was seen with increasing exposure to “any biological substance,” “any chemical substance,” or “any decontaminant” in the groups for

______________

1 The committee’s review of the literature also generated hypotheses of long-term effects from exposure to Staphylococcal enterotoxin type B, but a roster of individuals participating in this test was not available to test the hypotheses.

Suggested Citation:"6 Discussion." National Academies of Sciences, Engineering, and Medicine. 2016. Assessing Health Outcomes Among Veterans of Project SHAD (Shipboard Hazard and Defense). Washington, DC: The National Academies Press. doi: 10.17226/21846.
×

which there was sufficient sample size and variability in number of exposures to evaluate (see Table 4-12).2

Analysis of cause-specific mortality for the groups of participants exposed to “any biological substance,” “any chemical substance,” “any decontaminant,” and the tugs and Project SHAD technical staff found that the groups did not show significantly increased mortality from that of their comparison groups. The only statistically significant result suggesting increased risk for a Project SHAD participant group was an increase in the hazard ratio for heart disease among the crew of the USS George Eastman. Ischemic heart disease mortality contributed the greater portion to this increased hazard ratio, but was not itself statistically different in between SHAD participants and the comparison group. When the committee applied a statistical adjustment to take into account the multiple comparisons in the analysis of cause-specific mortality within the crew of the George Eastman, the result no longer attained statistical significance.

Interpretation of the Mortality Results

The previous IOM (2007) study of SHAD veterans (referred to as SHAD I) did not observe statistically significant differences in all-cause mortality between participants and the comparison group for the total study population. The results of the present study, with an additional 7 years of mortality follow-up, are similar. The SHAD I study found an elevation in heart disease mortality for SHAD veterans overall, and supplementary analyses following the SHAD I study (IOM, 2008) observed an elevated all-cause mortality risk for the crew of the USS George Eastman. The USS George Eastman was a ship specially outfitted for participation in SHAD testing and was involved in multiple tests. In the current study, an increase in heart disease risk was seen only for the crew of the USS George Eastman. However, it is important not to over-interpret the elevated heart disease risk seen in the current study, as an adjustment for the multiple testing carried out indicates the likelihood that this could have resulted from chance alone.

FINDINGS ON MORBIDITY

Morbidity in the study population was evaluated using records from automated databases from Medicare and the Veterans Health Administration (VHA). The Medicare data reflect claims for fee-for-service hospital or outpatient care during the period 1999-2011. Overall, 55 percent of the SHAD participants and 52 percent of the comparison population were enrolled in Medicare (Parts A or B) for some of this time. For most years, the SHAD test participants had slightly higher Medicare enrollment than the comparison population (see Table 5-1), which may reflect that the SHAD veterans were slightly older than the comparison population (see Table 4-1).

VHA records covered inpatient and outpatient care during the period 1997-2011. Up to 40 percent of Project SHAD participants and a third of the comparison population had diagnoses recorded; use of VHA services was consistently higher among SHAD veterans than the comparison population during the time examined (see Table 5-2). The committee noted that the proportionally greater use of VHA by Project SHAD participants became more marked starting in 2002 when the Department of Veterans Affairs (VA) sent letters to SHAD veterans informing them of their participation in SHAD tests and making available health evaluations at VA (see

______________

2 See Box 3-1 for a list of the test substances covered by each of these groups.

Suggested Citation:"6 Discussion." National Academies of Sciences, Engineering, and Medicine. 2016. Assessing Health Outcomes Among Veterans of Project SHAD (Shipboard Hazard and Defense). Washington, DC: The National Academies Press. doi: 10.17226/21846.
×

Figure 5-1). It seems plausible that this notification contributed to an increased use of VHA services by SHAD veterans. Other factors, including the possibility that the SHAD veteran population was consistently less healthy and sought care preferentially through VHA, may also have contributed but are harder to isolate.

The committee used two approaches to assessing morbidity. Consistent with the analysis of mortality, the entire Project SHAD participant population was compared to the total population that served on vessels and in airborne and ground units that were selected for the comparison population. In addition, exposure-specific comparisons were made between SHAD participants and the corresponding comparison groups to test hypotheses suggested by the scientific literature regarding health risks. Time and resources did not permit analysis of morbidity for the special exposure groups for which further exploratory mortality analyses were conducted. As with mortality, statistical adjustments for the multiple testing carried out were applied to the findings.

Overall, or all-cause, morbidity was evaluated using median hospital days per person-year of enrollment among Medicare enrollees hospitalized during the study period. Hospital days provide a measure of relatively significant illness of all kinds. Cause-specific morbidity was evaluating by looking at numbers of people with diagnoses in Medicare or VHA records. Broad categories from the ninth revision of the International Classification of Diseases (ICD-9) (WHO, 2015) were used for analyses of the population as a whole, and specific diagnoses were used in the analyses that focused on the health outcomes hypothesized for the substances of interest (see Table 3-1).

Overall Morbidity

Roughly 42 percent of both Project SHAD participant and comparison groups who had been enrolled in Medicare during the study period had a hospitalization during that time. Median hospital days per person-year of enrollment among those hospitalized was slightly lower among Project SHAD participants than the comparison group, but the difference was not statistically significant (see Table 5-3).

Cause-specific morbidity was examined using diagnoses from both Medicare and VHA records. The analysis of Medicare data considered broad ICD-9 categories of disease (see Table 5-4) as well as chronic conditions flagged by Medicare’s Chronic Condition Warehouse (CCW) (see Table 5-5). The CCW files indicate whether “treatment for the condition appears to have taken place” using claims-based algorithms (CMS, 2015).

For both broad categories of illness and specific chronic conditions, no statistically significant differences were seen between the Project SHAD participant and comparison groups.

Similarly, the percentages of those with diagnoses within major categories of illness in VA records were largely the same in the overall SHAD participant and comparison populations. The VA data provide different information than the Medicare data because a “true” number of people in the study who might have been able to use the VA system (for administrative, geographic, or other reasons) is not known. Instead, the denominator used in Table 5-6 is that of people who have sought care in VA in any of the years noted. The percentages of those with diagnoses are higher than in Medicare, probably because these are percentages of those seeking health care rather than of a general veteran population.

Suggested Citation:"6 Discussion." National Academies of Sciences, Engineering, and Medicine. 2016. Assessing Health Outcomes Among Veterans of Project SHAD (Shipboard Hazard and Defense). Washington, DC: The National Academies Press. doi: 10.17226/21846.
×

Hypotheses Regarding Specific Exposures and Morbidity

As noted above, the committee’s review of the scientific literature suggested the possibility that people exposed to C. burnetii, BPL, E. coli, sarin, or zinc cadmium sulfide might be at increased risk for certain adverse health effects. The hypotheses were tested by examining both overall morbidity and morbidity from the specific adverse health effects in the groups exposed to these substances.

Fifty-five to 65 percent of participants in the exposure and comparison groups were enrolled in Medicare during the period in question. From the VHA data it was seen that 40 percent to 47 percent of the SHAD veterans in these exposure groups had a diagnosis recorded in the VHA data and thus were known to have used the VHA system. Only 30 to 34 percent of those in the comparison groups were known to use the VHA system (see Table 5-7). The differences in use of VHA health care for most of these exposure groups was statistically significantly higher among the SHAD participants than for the comparison groups, even after correction for multiple testing. This result was consistent with heavier use of VHA health care seen for the Project SHAD participant group as a whole. As noted earlier, this higher level of use may have resulted from the letters of notification sent to Project SHAD participants that invited them to have a health assessment at VA. Of those enrolled in Medicare, 41 to 53 percent were hospitalized during the study period. Among those hospitalized, median hospital days per person-year of enrollment among the SHAD veterans in the exposure groups were not statistically greater than their comparison groups (see Table 5-8).

Finally, the committee used both Medicare and VHA data to assess whether the specific health outcomes hypothesized were observed more frequently in the SHAD veterans in these exposure groups than in the comparison groups. On the basis of the percentages of those enrolled in Medicare or who had used the VHA system who had a diagnosis of interest, the SHAD veterans and their comparison groups had similar results (see Table 5-9). Odds ratios for the counts showed no statistically significant differences.

Interpretation of Morbidity Results

The current study did not identify consistent differences in morbidity between Project SHAD participants and the comparison group for the study population as a whole or for specific exposure groups. The committee notes that the SHAD I study analyzed responses to a 2004 health survey that indicated worse health among the surviving SHAD veterans than the comparison group. However, the SHAD I health survey also collected reports of hospitalizations and found no significant differences, which is consistent with the finding of the current study.

THE STUDY’S STRENGTHS AND WEAKNESSES

Strengths of the Study

The current study benefited from a considerable investment of effort during the first IOM study (IOM, 2007) to establish and validate the cohort of Project SHAD test participants from ship logs and diaries. Except for the few cases where ship logs or rosters were not available,3 the

______________

3 Rosters were not available for the tug boats that participated in tests other than Shady Grove.

Suggested Citation:"6 Discussion." National Academies of Sciences, Engineering, and Medicine. 2016. Assessing Health Outcomes Among Veterans of Project SHAD (Shipboard Hazard and Defense). Washington, DC: The National Academies Press. doi: 10.17226/21846.
×

researchers were largely able to identify personnel sufficiently for follow-up. The SHAD I report (IOM, 2007) noted that, except for the personnel from Test 69-10, less than 6 percent of the study population lacked social security numbers, permitting fairly complete follow up.

The study also benefited from the input of SHAD veterans. At the start of this second SHAD study, the committee held two public meetings at which veterans were invited to share their experiences. At the second meeting, panels of men who had been part of the Project SHAD Technical Staff, the Copper Head test, and Test 69-10 recounted some of their memories of the testing and answered committee member questions (see Appendix B). These interactions with SHAD veterans helped the committee to better understand the context of the tests and the experience of those who had been present.

The study’s cohort design was strengthened by the use of a comparison group selected to be as similar as possible to the group with the exposure under study. In contrast to studies in which military personnel are compared to civilians, or deployed service members to the non-deployed, this study had the advantage of comparing groups who were deployed at the same time and in similar areas.

Another strength of this study is the length of follow up. By the end of the study followup period, December 31, 2011, nearly 50 years had elapsed since the earliest SHAD tests in 1963, and 42 years since the final tests in 1969. Because of this lengthy follow-up period, the study had an opportunity to assess the mortality experience of the study population across a broad range of causes of death, including those that appear later in life. Similarly, the long follow-up period made it feasible to turn to Medicare data to examine morbidity.

The availability of information on cause of death from the National Death Index for deaths from 1979 forward was another factor in making it possible to conduct a range of mortality analyses. The current study added to the mortality information available in SHAD I by also seeking death certificates for members of the study population who died before 1979. As described in Chapter 3 and Appendix D, nearly 200 additional death certificates were obtained through requests to individual states.

As previously noted, the SHAD I study relied on a survey to solicit reports from the surviving members of the study population on their health. Although such surveys make it possible to assess a broad range of indicators of health status, they depend for their validity on the accuracy and completeness of reporting by the respondents and on the response rate. They also require direct contact with each surviving member of the study population. Using Medicare and VHA databases made it possible to obtain highly detailed information on diagnoses made by medical professionals over multiple years for veterans who received care during the period for which records were obtained. Using these sources increases the quality of information for all included in this study and protects against the effects of differential mortality, recall bias, confusion about medical terminology, and health-related causes of non-response (e.g., persons who are sicker typically have lower response rates than those who are healthier, but they are more likely to appear in Medicare claims data because they receive more care).

Given the broad range of potential health outcomes, the study also benefited from the committee’s review of the literature concerning the agents, simulants, decontaminants and tracers used in the tests to formulate hypotheses to test in the study.

Weaknesses of the Study

Exposure misclassification has been referred to as “the Achilles’ heel” of environmental epidemiology. In this study the committee felt it was able to refine the representations of

Suggested Citation:"6 Discussion." National Academies of Sciences, Engineering, and Medicine. 2016. Assessing Health Outcomes Among Veterans of Project SHAD (Shipboard Hazard and Defense). Washington, DC: The National Academies Press. doi: 10.17226/21846.
×

exposure by taking into account the numbers of trials in which SHAD veterans had the opportunity to be exposed to a given test substance. However, this remains an indirect form of exposure assessment. Data were not available to determine the dose of a substance received by individual participants or, for most tests, the environmental concentrations of the test substances to which service members were exposed. Requests from the committee for declassification of such information from these tests were not approved by DoD.

Knowledge of one’s exposure status has the potential to bias the detection of the outcomes of interest because a person who considers himself exposed may be more likely to seek health care or recall health conditions than a person who does not consider himself exposed. In 2002, VA (2002) began notifying SHAD veterans that they had been part of the SHAD test program and that they could seek health assessments from VA. Since then, the SHAD participants have had time to seek health care and receive diagnoses that veterans in the comparison population may not have sought.

The SHAD tests took place during the Vietnam era; therefore both SHAD participants and the members of the comparison population may also have had service that makes them eligible for disability claims for certain conditions that VA has declared are presumptively related to Agent Orange exposure (VA, 2015). Since the early 1990s, growing numbers of Vietnam veterans have been deemed to have service-related conditions related to Agent Orange exposure. As of January 2015, more than a dozen medical conditions are included (e.g., diabetes, ischemic heart disease, lung cancer, prostate cancer, and Parkinson’s disease). Eligibility has also been expanded to include not only personnel who served as ground troops in Vietnam, but also (on a case-by-case basis) the “blue-water” Navy service members as well as some veterans with service in Korea or Thailand (VA, 2015).

A potential weakness of the study is an inability to tell whether participant and control populations had similar levels of exposure to service in Vietnam. In addition to potential exposure to Agent Orange, traumatic experience increases risks to mental and physical health (e.g., Boscarino, 2008). The extent to which the two groups differ on Vietnam-related service is not known, but VA records indicate similar percentages of Vietnam service among the SHAD participants (17.4 percent) and the comparison population (18.4 percent) that had filed a disability claim (see Table 4-1).

Another aspect of the analysis is that while mortality data were available for the entire period since the time of the testing, morbidity data were available only for the period beginning in the late 1990s. Thus, health effects arising soon after exposure could be detected in these analyses only if they led to higher mortality or highly persistent morbidity.

Finally, the committee’s use of hypotheses generated from the literature provided some focus for the analyses, but in assessing the health status of SHAD participants and the comparison groups for various categories of exposures the committee carried out many statistical tests, increasing the likelihood that statistically significant associations could arise by chance. In some cases the exposure groups were of modest size, which could make it difficult to ascertain any true subtle differences in either mortality or morbidity.

ANALYTICAL CHALLENGES

This analysis proved to be challenging for several reasons. First, the Medicare and VHA data can be broadly interpreted as indications of health by their reflection of diagnoses that lead to health care use. The Medicare data for enrollees over age 65 can be interpreted as providing

Suggested Citation:"6 Discussion." National Academies of Sciences, Engineering, and Medicine. 2016. Assessing Health Outcomes Among Veterans of Project SHAD (Shipboard Hazard and Defense). Washington, DC: The National Academies Press. doi: 10.17226/21846.
×

population-based measures; however, the VHA data generally cannot be because of the variable criteria associated with eligibility for these services and the decision-making process associated with their use. Second, at no time was the entire Project SHAD participant cohort eligible for Medicare. Thus, the committee’s analysis had to focus on the morbidity of the oldest veterans, who were also the oldest at the time of the testing. Finally, the data themselves are quite complex. Once enrolled in Medicare, each person will have one annual enrollment record but will have variable numbers of physician, hospital, and medication records that contain information about diagnoses. These records need to be combined into specific yes/no variables such as “diagnosis of neurological disorder.” With Medicare enrollment beginning at age 65, the identified cases reflect a combination of existing (prevalent) disease at age 65 and new (incident) disease diagnosed after age 65. These features of the data on the timing of health outcomes, combined with the challenges associated with assessing exposure, resulted in a study with many analytical complexities.

OTHER CONCERNS

Continued Classification of the Test Documents

As noted in Chapter 1, the committee requested declassification of additional data pertaining to the tests and exposures. Ultimately, no additional materials were declassified and made available to the committee, out of concern that vulnerabilities that might have been identified by the SHAD testing could still be relevant despite turnover in the naval fleet. The committee notes that the information that remains classified might have informed understanding of the range of concentrations of test substances to which participants might have been exposed, but information about the location of personnel on the vessels during the tests and the doses they may have received would still have been absent. The statistical analyses would still be based on comparing exposure groups. As a result, the committee does not expect that access to the classified information would have altered the findings of the analysis.

Human Health and Ethics

In the decades that have passed since the SHAD testing, views on both workplace safety and the inclusion of humans (intentionally or not) in experimental testing have undergone a major evolution and emphasize the importance of informing workers (including military service personnel) of the chemicals (and potential health risk) they may be exposed to. The approximately 5,900 military personnel reported to have been included in the Project SHAD testing were not unknowingly participating in human-subjects research, but because of the security around the testing, service personnel were not necessarily aware of the purposes of the testing and the agents being used. Review of the test plans and descriptions of the tests show that the intent of the program was to evaluate operational characteristics of ships and protective and dissemination equipment as well as the behavior of test agents in marine environments.

While it is evident that the intent of SHAD was not to evaluate the health impact of exposure to the substances used in the tests, animals were used in some of the tests and reportedly exposed to deadly or dangerous agents. In a few tests to evaluate personal protective equipment (e.g., Autumn Gold, DTC 69-10, Copper Head), samples such as gargle samples or chemical dosimeters on clothing were collected from service members. The secrecy surrounding

Suggested Citation:"6 Discussion." National Academies of Sciences, Engineering, and Medicine. 2016. Assessing Health Outcomes Among Veterans of Project SHAD (Shipboard Hazard and Defense). Washington, DC: The National Academies Press. doi: 10.17226/21846.
×

the tests, the use of animal testing, and the human biological samples obtained could have led to a perception that the personnel on the tests were either purposefully or inadvertently exposed to agents with the potential for human health risk.

Although the committee was cognizant of the questions raised by veterans and others about the ethics and legality of the SHAD testing, it was not charged with reviewing the merits of the program. Its focus had to be on the scientific question of whether test participation is associated with adverse long-term health effects.

CONCLUSIONS

Epidemiological studies such as this investigation of health outcomes among veterans of the SHAD tests are complex undertakings requiring substantial time and resources. The committee invested considerable effort in learning about the SHAD tests and in formulating its approaches to data analysis. In the numerous analyses of both the full study population and of several subgroups, the only finding of a seemingly higher risk—of heart disease mortality among the 356 men who served on the USS George Eastman—did not attain statistical significance after adjustments for the multiple tests carried out on this group. The vast majority of the analyses showed no evidence of different health outcomes among SHAD veterans relative to the comparison group. The committee recognizes that with the limitations of epidemiological studies these negative findings cannot unequivocally rule out some potential effect from the SHAD testing. However, within the limits of the data available to the committee, the results of the analyses provide no evidence that the health of SHAD veterans overall or those in the exposure groups is significantly different from that of similar veterans who did not participate in these tests.

REFERENCES

Boscarino, J. A. 2008. A prospective study of PTSD and early-age heart disease mortality among Vietnam veterans: Implications for surveillance and prevention. Psychosomatic Medicine 70:668-676.

CMS (Centers for Medicare & Medicaid Services). 2015. Chronic conditions data warehouse. https://www.ccwdata.org/web/guest/condition-categories (accessed October 23, 2015).

IOM (Institute of Medicine). 2007. Long-term health effects of participation in Project SHAD (Shipboard Hazard and Defense). Washington, DC: The National Academies Press.

IOM. 2008. Response to 15 February 2008 letter from Congressmen Mike Thompson and Dennis Rehberg. http://iom.nationalacademies.org/~/media/Files/Report%20Files/2007/Long-Term-Health-Effects-of-Participation-in-Project-SHAD-Shipboard-Hazard-and-Defense/SHAD%20Response%20Letter.pdf (accessed October 7, 2015).

VA (Department of Veterans Affairs). 2002. VA contacts “Project SHAD” veterans. http://www.va.gov/opa/pressrel/pressrelease.cfm?id=457 (accessed October 27, 2015).

VA. 2015. Public health: Agent Orange Registry health exam for veterans. http://www.publichealth.va.gov/exposures/agentorange/benefits/registry-exam.asp (accessed October 26, 2015).

WHO (World Health Organization). 2015. International Classification of Diseases (ICD). http://www.who.int/classifications/icd/en (accessed August 4, 2015).

Suggested Citation:"6 Discussion." National Academies of Sciences, Engineering, and Medicine. 2016. Assessing Health Outcomes Among Veterans of Project SHAD (Shipboard Hazard and Defense). Washington, DC: The National Academies Press. doi: 10.17226/21846.
×

This page intentionally left blank.

Suggested Citation:"6 Discussion." National Academies of Sciences, Engineering, and Medicine. 2016. Assessing Health Outcomes Among Veterans of Project SHAD (Shipboard Hazard and Defense). Washington, DC: The National Academies Press. doi: 10.17226/21846.
×
Page 105
Suggested Citation:"6 Discussion." National Academies of Sciences, Engineering, and Medicine. 2016. Assessing Health Outcomes Among Veterans of Project SHAD (Shipboard Hazard and Defense). Washington, DC: The National Academies Press. doi: 10.17226/21846.
×
Page 106
Suggested Citation:"6 Discussion." National Academies of Sciences, Engineering, and Medicine. 2016. Assessing Health Outcomes Among Veterans of Project SHAD (Shipboard Hazard and Defense). Washington, DC: The National Academies Press. doi: 10.17226/21846.
×
Page 107
Suggested Citation:"6 Discussion." National Academies of Sciences, Engineering, and Medicine. 2016. Assessing Health Outcomes Among Veterans of Project SHAD (Shipboard Hazard and Defense). Washington, DC: The National Academies Press. doi: 10.17226/21846.
×
Page 108
Suggested Citation:"6 Discussion." National Academies of Sciences, Engineering, and Medicine. 2016. Assessing Health Outcomes Among Veterans of Project SHAD (Shipboard Hazard and Defense). Washington, DC: The National Academies Press. doi: 10.17226/21846.
×
Page 109
Suggested Citation:"6 Discussion." National Academies of Sciences, Engineering, and Medicine. 2016. Assessing Health Outcomes Among Veterans of Project SHAD (Shipboard Hazard and Defense). Washington, DC: The National Academies Press. doi: 10.17226/21846.
×
Page 110
Suggested Citation:"6 Discussion." National Academies of Sciences, Engineering, and Medicine. 2016. Assessing Health Outcomes Among Veterans of Project SHAD (Shipboard Hazard and Defense). Washington, DC: The National Academies Press. doi: 10.17226/21846.
×
Page 111
Suggested Citation:"6 Discussion." National Academies of Sciences, Engineering, and Medicine. 2016. Assessing Health Outcomes Among Veterans of Project SHAD (Shipboard Hazard and Defense). Washington, DC: The National Academies Press. doi: 10.17226/21846.
×
Page 112
Suggested Citation:"6 Discussion." National Academies of Sciences, Engineering, and Medicine. 2016. Assessing Health Outcomes Among Veterans of Project SHAD (Shipboard Hazard and Defense). Washington, DC: The National Academies Press. doi: 10.17226/21846.
×
Page 113
Suggested Citation:"6 Discussion." National Academies of Sciences, Engineering, and Medicine. 2016. Assessing Health Outcomes Among Veterans of Project SHAD (Shipboard Hazard and Defense). Washington, DC: The National Academies Press. doi: 10.17226/21846.
×
Page 114
Next: Appendix A: Committee and Consultant Biographies »
Assessing Health Outcomes Among Veterans of Project SHAD (Shipboard Hazard and Defense) Get This Book
×
Buy Paperback | $50.00 Buy Ebook | $39.99
MyNAP members save 10% online.
Login or Register to save!
Download Free PDF

Between 1963 and 1969, the U.S. military carried out a series of tests, termed Project SHAD (Shipboard Hazard and Defense), to evaluate the vulnerabilities of U.S. Navy ships to chemical and biological warfare agents. These tests involved use of active chemical and biological agents, stimulants, tracers, and decontaminants. Approximately 5,900 military personnel, primarily from the Navy and Marine Corps, are reported to have been included in Project SHAD testing.

In the 1990s some veterans who participated in the SHAD tests expressed concerns to the Department of Veterans Affairs (VA) that they were experiencing health problems that might be the result of exposures in the testing. These concerns led to a 2002 request from VA to the Institute of Medicine (IOM) to carry out an epidemiological study of the health of SHAD veterans and a comparison population of veterans who had served on similar ships or in similar units during the same time period. In response to continuing concerns, Congress in 2010 requested an additional IOM study. This second study expands on the previous IOM work by making use of additional years of follow up and some analysis of diagnostic data from Medicare and the VA health care system.

  1. ×

    Welcome to OpenBook!

    You're looking at OpenBook, NAP.edu's online reading room since 1999. Based on feedback from you, our users, we've made some improvements that make it easier than ever to read thousands of publications on our website.

    Do you want to take a quick tour of the OpenBook's features?

    No Thanks Take a Tour »
  2. ×

    Show this book's table of contents, where you can jump to any chapter by name.

    « Back Next »
  3. ×

    ...or use these buttons to go back to the previous chapter or skip to the next one.

    « Back Next »
  4. ×

    Jump up to the previous page or down to the next one. Also, you can type in a page number and press Enter to go directly to that page in the book.

    « Back Next »
  5. ×

    Switch between the Original Pages, where you can read the report as it appeared in print, and Text Pages for the web version, where you can highlight and search the text.

    « Back Next »
  6. ×

    To search the entire text of this book, type in your search term here and press Enter.

    « Back Next »
  7. ×

    Share a link to this book page on your preferred social network or via email.

    « Back Next »
  8. ×

    View our suggested citation for this chapter.

    « Back Next »
  9. ×

    Ready to take your reading offline? Click here to buy this book in print or download it as a free PDF, if available.

    « Back Next »
Stay Connected!