LETTERS LOSING THE FOREST FOR THE TREES Huguet et al.1 examined the impact of netting out aggregated suicide counts among current military personnel on estimates of veteran suicide rates derived from National Violent Death Reporting System (NVDRS) data. They found that recent suicide rates among younger, but not older veterans were markedly higher than rates among age- and gender-matched nonveterans, even after crude adjustment for (aggregate counts of) current military decedents. The extent of the adjustment (and possibility of overadjustment) is unclear because the authors do not indicate whether they netted out only active duty military suicides that occurred in the United States, as should be the case since active duty suicides occurring outside the United States would not be picked up in NVDRS. These findings, like those by Gibbons et al.,2 are sobering and of interest. What is surprising, however, is that the article’s title, abstract, and Discussion section entirely ignore the empirical finding of strong effect modification by age, in favor of asserting that (1) policymakers should be “reassured” that suicide estimates “derived from the NVDRS are reliable,”
Letters to the editor referring to a recent Journal article are encouraged up to 3 months after the article's appearance. By submitting a letter to the editor, the author gives permission for its publication in the Journal. Letters should not duplicate material being published or submitted elsewhere. The editors reserve the right to edit and abridge letters and to publish responses. Text is limited to 400 words and 10 references. Submit online at www. editorialmanager.com/ajph for immediate Web posting, or at ajph.edmgr.com for later print publication. Online responses are automatically considered for print publication. Queries should be addressed to the Editor-in-Chief, Mary E. Northridge, PhD, MPH, at [email protected].
and “minimally affected by the adjustment,” and (2) NVDRS constitutes “a valid surveillance system for veteran suicide.” These assertions are, respectively, contradicted by the data presented (e.g., suicide rates among young veterans fell by more than 50% after netting out decedents presumed to be current military) and more sweeping than the current study warrants absent a comparison at the individual level with a gold standard for veteran status (i.e., regarding whether a given suicide was, at the time of death, current or former military). More importantly for suicide prevention efforts, the approach by Huguet et al. nets out an aggregate number of decedents, rather than particular suicides, because the authors are unable to determine which decedents ever served and which were currently serving when they died. This failure renders NVDRS a mere aggregator of death certificate data. What is lost is precisely what makes NVDRS so useful: information about the circumstances pertinent to different categories of suicides. To seriously attend to the current high burden of suicide apparent among soldiers and young veterans it is important to not only measure the extent of burden accurately, but also to understand whether, and if so, how this burden is explained by cohort effects affecting soldiers and younger veterans, factors related to selection into the armed forces, experiences during service, access to lethal means, and—in the case of veterans—circumstances related to recent discharge from service. A linked data set that matched all known US service members, data related to their selection into and separation from military service, and the National Death Index (NDI) would free researchers and policy makers from the assumption-laden best guesses of researchers, who like Huguet et al., try to make the best of a limited data set. The standard for studies of this kind remains those by Kang and Bullman,3---5 who linked Department of Defense records to the NDI, allowing them to unequivocally identify current and former military and describe the circumstances pertinent to both. If and when such linked data
May 2014, Vol 104, No. 5 | American Journal of Public Health
become readily available to researchers—a technically trivial but perhaps politically nontrivial if and when—better policy and clinical care will follow. j Matthew Miller, MD, ScD Deborah Azrael, PhD Catherine Barber, MPA Robert Bossarte, PhD
About the Authors Matthew Miller, Deborah Azrael, and Catherine Barber are with the Harvard Injury Control Research Center, Boston, MA. Matthew Miller is also with the Department of Health Policy and Management, Harvard School of Public Health, Boston. Robert Bossarte is with the Center of Excellence for Suicide Prevention, Veterans Affairs Medical Center, Canandaigua, NY. Correspondence should be sent to Matthew Miller, MD, ScD, Co-Director, Harvard Injury Control Research Center, Associate Professor of Health Policy and Management, Department of Health Policy and Management, Harvard School of Public Health, 677 Huntigton Ave, Boston, MA 02115 (e-mail: [email protected]). Reprints can be ordered at http://www.ajph.org by clicking on the “Reprints” link. This letter was accepted December 10, 2013. doi:10.2105/AJPH.2013.301843
References 1. Huguet N, Kaplan M, McFarland B. The effects of misclassification biases on veteran suicide rate estimates. Am J Public Health. 2014;104(1):151---155. 2. Gibbons RD, Brown CH, Hur K. Is the rate of suicide among veterans elevated? Am J Public Health. 2012;102 (suppl 1):S17---S19. 3. Kang HK, Bullman TA. Risk of suicide among US veterans after returning from the Iraq or Afghanistan war zones. JAMA. 2008;300(6):652---653. 4. Kang HK, Bullman TA. Mortality among US veterans of the Persian Gulf War. N Engl J Med. 1996;335: 1498---1504. 5. Kang HK, Bullman TA. Mortality among US veterans of the Gulf War: seven year follow-up. Am J Epidemiol. 2001;154:399---405.
HUGUET ET AL. RESPOND We thank Miller et al. for their comments. Unfortunately, Miller et al. seem to have missed the essence of our study, which examined the potential effect that misclassification of current military personnel (active duty, National
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LETTERS
Guard, Reserves) and undetermined deaths could have on veteran suicide rate estimates derived from death certificates. Aggregate suicide data are the basis of violent death surveillance and are essential to evaluate changes in suicide trends and inform suicide prevention efforts.1 Unfortunately, death certificates do not clearly define veteran status. Consequently, much has been written about potential limitations of this data element in estimating suicide rates.2 To use the language of Miller et al., our work shows that these possible limitations are minor “trees” that might obscure the “forest.” As clearly indicated in our study, younger current military suicide decedents may be at greater risk of being misclassified as veterans on death certificates. But even after adjustment for misclassification, this group remained at higher risk than their nonveteran counterparts. In fact, our study points out that, “[d]espite the reduction in the number of younger veteran suicides, the results revealed that male and female veterans of all ages had higher suicide rates than nonveterans.” While ideally we want to know whether the decedent was currently versus formerly in the military at the time of death, we think that the more pertinent information to ascertain is whether the individual died by suicide. In our view, the “gold standard” should be living people. We fear that policymakers may be distracted by minutia rather than focus on veterans health. Consequently, our study aimed at determining whether these biases affecting the designation of veteran status on the death certificate would render suicide estimates useless to policymakers. We found veterans to be at elevated risk of suicide. Thus, the “forest” is the provision of services needed to help veterans avoid suicide. With the aim of improving veterans health, we endorse the call by Miller et al. for greater access to linked data. However, the issue is not simply to link data with the National Death Index. Rather, as a national imperative, we need to improve the quality of data derived from the death investigation system so as to provide useful mortality statistics. But, more than 20 veterans die by suicide every day.3 Can we afford to wait for more precise data or should we rely on the best available information to try to save lives now? j
e2 | Letters
Nathalie Huguet, PhD Mark S. Kaplan, DrPH Bentson H. McFarland, MD, PhD
About the Authors Nathalie Huguet is with the Center for Public Health Studies, Portland State University, Portland, OR. Mark S. Kaplan is with the Department of Social Welfare, UCLA Luskin School of Public Affairs, University of California, Los Angeles. Bentson H. McFarland is with the Department of Psychiatry, Oregon Health & Science University, Portland. Correspondence should be sent to Nathalie Huguet, PhD, Center for Public Health Studies, Portland State University, PO Box 751, Portland, OR 97207 (e-mail: [email protected]). Reprints can be ordered at http://www.ajph.org by clicking the “Reprints” link. This letter was accepted December 19, 2013. doi:10.2105/AJPH.2013.301856
Contributors The authors contributed equally to the writing of this letter.
References 1. Campbell R, Weis Ma, Millet L, et al. From surveillance to action: early gains from the National Violent Death Reporting System. Inj Prev. 2006;12(suppl 2):ii6---ii9. 2. US Department of Veterans Affairs. Report of the Blue Ribbon Work Group Report on suicide prevention in the veteran population. 2008. Available at: http://www. mentalhealth.va.gov/suicide_prevention/Blue_Ribbon_ Report-FINAL_June-30-08.pdf. Accessed December 17, 2013. 3. Kemp J, Bossarte RM. Suicide data report, 2012. US Department of Veterans Affairs. 2012. Available at: http://www.va.gov/opa/docs/Suicide-Data-Report-2012final.pdf. Accessed December 16, 2013.
American Journal of Public Health | May 2014, Vol 104, No. 5
Letters to the editor referring to a recent Journal article are encouraged up to 3 months after the article's appearance. By submitting a letter to the editor, the author gives permission for its publication in the Journal. Letters should not duplicate material being published or submitted elsewhere. The editors reserve the right to edit and abridge letters and to publish responses. Text is limited to 400 words and 10 references. Submit online at www. editorialmanager.com/ajph for immediate Web posting, or at ajph.edmgr.com for later print publication. Online responses are automatically considered for print publication. Queries should be addressed to the Editor-in-Chief, Mary E. Northridge, PhD, MPH, at [email protected].
and “minimally affected by the adjustment,” and (2) NVDRS constitutes “a valid surveillance system for veteran suicide.” These assertions are, respectively, contradicted by the data presented (e.g., suicide rates among young veterans fell by more than 50% after netting out decedents presumed to be current military) and more sweeping than the current study warrants absent a comparison at the individual level with a gold standard for veteran status (i.e., regarding whether a given suicide was, at the time of death, current or former military). More importantly for suicide prevention efforts, the approach by Huguet et al. nets out an aggregate number of decedents, rather than particular suicides, because the authors are unable to determine which decedents ever served and which were currently serving when they died. This failure renders NVDRS a mere aggregator of death certificate data. What is lost is precisely what makes NVDRS so useful: information about the circumstances pertinent to different categories of suicides. To seriously attend to the current high burden of suicide apparent among soldiers and young veterans it is important to not only measure the extent of burden accurately, but also to understand whether, and if so, how this burden is explained by cohort effects affecting soldiers and younger veterans, factors related to selection into the armed forces, experiences during service, access to lethal means, and—in the case of veterans—circumstances related to recent discharge from service. A linked data set that matched all known US service members, data related to their selection into and separation from military service, and the National Death Index (NDI) would free researchers and policy makers from the assumption-laden best guesses of researchers, who like Huguet et al., try to make the best of a limited data set. The standard for studies of this kind remains those by Kang and Bullman,3---5 who linked Department of Defense records to the NDI, allowing them to unequivocally identify current and former military and describe the circumstances pertinent to both. If and when such linked data
May 2014, Vol 104, No. 5 | American Journal of Public Health
become readily available to researchers—a technically trivial but perhaps politically nontrivial if and when—better policy and clinical care will follow. j Matthew Miller, MD, ScD Deborah Azrael, PhD Catherine Barber, MPA Robert Bossarte, PhD
About the Authors Matthew Miller, Deborah Azrael, and Catherine Barber are with the Harvard Injury Control Research Center, Boston, MA. Matthew Miller is also with the Department of Health Policy and Management, Harvard School of Public Health, Boston. Robert Bossarte is with the Center of Excellence for Suicide Prevention, Veterans Affairs Medical Center, Canandaigua, NY. Correspondence should be sent to Matthew Miller, MD, ScD, Co-Director, Harvard Injury Control Research Center, Associate Professor of Health Policy and Management, Department of Health Policy and Management, Harvard School of Public Health, 677 Huntigton Ave, Boston, MA 02115 (e-mail: [email protected]). Reprints can be ordered at http://www.ajph.org by clicking on the “Reprints” link. This letter was accepted December 10, 2013. doi:10.2105/AJPH.2013.301843
References 1. Huguet N, Kaplan M, McFarland B. The effects of misclassification biases on veteran suicide rate estimates. Am J Public Health. 2014;104(1):151---155. 2. Gibbons RD, Brown CH, Hur K. Is the rate of suicide among veterans elevated? Am J Public Health. 2012;102 (suppl 1):S17---S19. 3. Kang HK, Bullman TA. Risk of suicide among US veterans after returning from the Iraq or Afghanistan war zones. JAMA. 2008;300(6):652---653. 4. Kang HK, Bullman TA. Mortality among US veterans of the Persian Gulf War. N Engl J Med. 1996;335: 1498---1504. 5. Kang HK, Bullman TA. Mortality among US veterans of the Gulf War: seven year follow-up. Am J Epidemiol. 2001;154:399---405.
HUGUET ET AL. RESPOND We thank Miller et al. for their comments. Unfortunately, Miller et al. seem to have missed the essence of our study, which examined the potential effect that misclassification of current military personnel (active duty, National
Letters | e1
LETTERS
Guard, Reserves) and undetermined deaths could have on veteran suicide rate estimates derived from death certificates. Aggregate suicide data are the basis of violent death surveillance and are essential to evaluate changes in suicide trends and inform suicide prevention efforts.1 Unfortunately, death certificates do not clearly define veteran status. Consequently, much has been written about potential limitations of this data element in estimating suicide rates.2 To use the language of Miller et al., our work shows that these possible limitations are minor “trees” that might obscure the “forest.” As clearly indicated in our study, younger current military suicide decedents may be at greater risk of being misclassified as veterans on death certificates. But even after adjustment for misclassification, this group remained at higher risk than their nonveteran counterparts. In fact, our study points out that, “[d]espite the reduction in the number of younger veteran suicides, the results revealed that male and female veterans of all ages had higher suicide rates than nonveterans.” While ideally we want to know whether the decedent was currently versus formerly in the military at the time of death, we think that the more pertinent information to ascertain is whether the individual died by suicide. In our view, the “gold standard” should be living people. We fear that policymakers may be distracted by minutia rather than focus on veterans health. Consequently, our study aimed at determining whether these biases affecting the designation of veteran status on the death certificate would render suicide estimates useless to policymakers. We found veterans to be at elevated risk of suicide. Thus, the “forest” is the provision of services needed to help veterans avoid suicide. With the aim of improving veterans health, we endorse the call by Miller et al. for greater access to linked data. However, the issue is not simply to link data with the National Death Index. Rather, as a national imperative, we need to improve the quality of data derived from the death investigation system so as to provide useful mortality statistics. But, more than 20 veterans die by suicide every day.3 Can we afford to wait for more precise data or should we rely on the best available information to try to save lives now? j
e2 | Letters
Nathalie Huguet, PhD Mark S. Kaplan, DrPH Bentson H. McFarland, MD, PhD
About the Authors Nathalie Huguet is with the Center for Public Health Studies, Portland State University, Portland, OR. Mark S. Kaplan is with the Department of Social Welfare, UCLA Luskin School of Public Affairs, University of California, Los Angeles. Bentson H. McFarland is with the Department of Psychiatry, Oregon Health & Science University, Portland. Correspondence should be sent to Nathalie Huguet, PhD, Center for Public Health Studies, Portland State University, PO Box 751, Portland, OR 97207 (e-mail: [email protected]). Reprints can be ordered at http://www.ajph.org by clicking the “Reprints” link. This letter was accepted December 19, 2013. doi:10.2105/AJPH.2013.301856
Contributors The authors contributed equally to the writing of this letter.
References 1. Campbell R, Weis Ma, Millet L, et al. From surveillance to action: early gains from the National Violent Death Reporting System. Inj Prev. 2006;12(suppl 2):ii6---ii9. 2. US Department of Veterans Affairs. Report of the Blue Ribbon Work Group Report on suicide prevention in the veteran population. 2008. Available at: http://www. mentalhealth.va.gov/suicide_prevention/Blue_Ribbon_ Report-FINAL_June-30-08.pdf. Accessed December 17, 2013. 3. Kemp J, Bossarte RM. Suicide data report, 2012. US Department of Veterans Affairs. 2012. Available at: http://www.va.gov/opa/docs/Suicide-Data-Report-2012final.pdf. Accessed December 16, 2013.
American Journal of Public Health | May 2014, Vol 104, No. 5
