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Research Methodology, Exposure Assessment, and Biomarkers Publications

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2023

  • Trace and Major Element Concentrations in Cadaveric Lung Tissues from World Trade Center Health Registry Decedents and Community Controls
    • A WTC Health Registry study suggests that major and trace elements from the WTC disaster remained in human lung tissues 6–10 years after the event. Continued work is needed to explore these elements as survivors' exposure biomarkers. 
    • Marmor, M., Burcham, J. L., Chen, L.-C., Chillrud, S. N., Graham, J. K., Jordan, H. T., Zhong, M., Halzack, E., Cone, J. E., & Shao, Y. (2023). Trace and Major Element Concentrations in Cadaveric Lung Tissues from World Trade Center Health Registry Decedents and Community Controls. International Journal of Environmental Research and Public Health, 20(20), 6923. https://doi.org/10.3390/ijerph23010010

2022

  • Trajectories of posttraumatic stress symptoms following the September 11, 2001, terrorist attacks: A comparison of two modeling approaches
    • This study measured the relationships among asthma, mental health, and quality of life. Changes in mental health caused changes in asthma control and change in asthma control affected a change in quality of life.
    • Huber, K. A., Frazier, P. A., Alper, H. E., & Brackbill, R. R. (2022). Trajectories of posttraumatic stress symptoms following the September 11, 2001, terrorist attacks: A comparison of two modeling approaches. Journal of Traumatic Stress, 35(2), 508–520. https://doi.org/10.1002/jts.22763 
  • The World Trade Center Health Program: an introduction to best practices
    • The papers in this issue of the Archives talk about how doctors should take care of people who were affected by the World Trade Center (WTC) disaster. The goal of this update is to make sure that the medical care given to people in the WTC Health Program is adequate. A group of doctors who work with the WTC Health Program started working on this update in April 2021. They know that doctors are very busy, so they made these papers short and easy to understand. Each paper talks about a specific health issue and includes a short summary of research of people at the WTC, and what doctors should do to diagnose and treat it. The papers also tell where to find more information about the WTC Health Program's coverage for diagnosing and treating these conditions. 
    • Calvert, G. M., Anderson, K., Cochran, J., Cone, J. E., Harrison, D. J., Haugen, P. T., Lilly, G., Lowe, S. M., Luft, B. J., Moline, J. M., Reibman, J., Rosen, R., Udasin, I. G., & Werth, A. S. (2023). The World Trade Center Health Program: An introduction to best practices. Archives of Environmental & Occupational Health, 78(4), 199–205. https://doi.org/10.1080/19338244.2022.2156975 

2021

  • 9/11 Health Update
    • A review examined research on the long-term health effects of the September 11 attacks. The studies found links between 9/11 exposure and problems with memory, mental health, cancer, breathing, and death. PTSD and depression were also linked to memory problems and other health concerns. The review highlights the need for continued research, health monitoring, and better treatments for people affected by 9/11. It also identifies areas where more research is needed to improve care.
    • Cone, J. E., Santiago-Colón, A., & Lucchini, R. (2021). 9/11 Health Update. International Journal of Environmental Research and Public Health, 18(12), 6383. https://doi.org/10.3390/ijerph18126383
  • Web and paper survey mode patterns and preferences, Health & Employment Survey, World Trade Center Health Registry
    • In this study, we looked at patterns of enrollee responses to the 2017–2018 Health & Employment Survey (HES). The overall completion rate was 65%. The likelihood of responding to HES was more than doubled when the web survey was an option compared to paper survey only (when enrollees did not have a valid email address on record). Most web surveys were received during the first two months of data collection compared with less than one-third of paper surveys. Multiple email reminders resulted in increased responses. To offer both mode options to all enrollees, more efforts should be made on collecting valid email addresses.
    • Seil, Mph, K., Yu, PhD, Ma, S., Brackbill, PhD, Mph, R., & Turner, Mph, L. (2021). Web and paper survey mode patterns and preferences, Health & Employment Survey, World Trade Center Health Registry. Survey Practice, 14(1), 1–12. https://doi.org/10.29115/SP-2021-0006 
  • Comparison of Prevalence and Exposure-Disease Associations Using Self-Report and Hospitalization Data Among Enrollees of the World Trade Center Health Registry
    • This research looked at how people's responses compared to what people say about their health and what hospitals reported about their health regarding long-term diseases after the 9/11 attacks. The study found a disagreement between the two sources. So, when deciding which source to use for research, it's important to consider factors like what's available and the goals of the study.
    • Alper, H. E., Brite, J., Cone, J. E., & Brackbill, R. M. (2021). Comparison of prevalence and exposure-disease associations using self-report and hospitalization data among enrollees of the world trade center health registry. BMC Medical Research Methodology, 21(1), 162. https://doi.org/10.1186/s12874-021-01358-y 
  • Cognitive impairment, and World Trade Centre-related exposures Trade Centre-related exposures
    • The article shows the ways those exposed to 9/11 might have cognitive impairment and that there are treatments. Physical activity and treatment of PTSD symptoms can help. The research will continue because 9/11 survivors may have a greater risk for this condition than others. 
    • Clouston, S. A. P., Hall, C. B., Kritikos, M., Bennett, D. A., DeKosky, S., Edwards, J., Finch, C., Kreisl, W. C., Mielke, M., Peskind, E. R., Raskind, M., Richards, M., Sloan, R. P., Spiro, A., Vasdev, N., Brackbill, R., Farfel, M., Horton, M., Lowe, S., … Luft, B. J. (2022). Cognitive impairment and World Trade Centre-related exposures. Nature Reviews Neurology, 18(2), 103–116. https://doi.org/10.1038/s41582-021-00576-8

2020

  • Post-traumatic stress disorder among survivors of the September 11, 2001 World Trade Center attacks: a review of the literature
    • This paper is based on a review of studies published between 2002 and 2019 on post-traumatic stress disorder (PTSD) among adult civilian survivors of 9/11 who were directly exposed. The review considered a number of aspects of each published study. These included the study design, timeframe, reported prevalence and persistence of PTSD and conditions that co-occurred with PTSD. several. This review paper further emphasizes that PTSD continues to be a critical area for understanding survivors’ emotional and physical development after 9/11 and makes recommendation for future research.
    • Hamwey, M. K., Gargano, L. M., Friedman, L. G., Leon, L. F., Petrsoric, L. J., & Brackbill, R. M. (2020). Post-Traumatic Stress Disorder among Survivors of the September 11, 2001 World Trade Center Attacks: A Review of the Literature. International Journal of Environmental Research and Public Health, 17(12), 4344. https://doi.org/10.3390/ijerph17124344
  • An introduction to probabilistic record linkage with a focus on linkage processing for WTC Registries
    • This paper is about record linkage which is combining records from different sources. This is done to increase the amount of information available for studies. There are different types of record linkage. The main type uses the likelihood that the same persons is in each source. This is called probabilistic record linkage. Three types of probabilistic record linkage are described. Other problems such as making sure information is useful and that the information is protected are discussed. Using record linkage for studying long-term complications of disasters, such as 9/11 are also discussed.
    • Asher, J., Resnick, D., Brite, J., Brackbill, R., & Cone, J. (2020). An Introduction to Probabilistic Record Linkage with a Focus on Linkage Processing for WTC Registries. International Journal of Environmental Research and Public Health, 17(18), 6937. https://doi.org/10.3390/ijerph17186937 

2019

  • Persistent mental and physical health impact of exposure to the September 11, 2001 World Trade Center terrorist attacks
    • This study found nearly half of enrollees of 9/11-exposed reported having developed one or more of the health conditions. Participants with PTSD or depression reported the worst health-related quality of life. They also had the highest levels of unmet need for mental health care. This suggests increased efforts to reach this group are needed.
    • Jordan, H. T., Osahan, S., Li, J., Stein, C. R., Friedman, S. M., Brackbill, R. M., Cone, J. E., Gwynn, C., Mok, H. K., & Farfel, M. R. (2019). Persistent mental and physical health impact of exposure to the September 11, 2001 World Trade Center terrorist attacks. Environmental Health, 18(1), 12. https://doi.org/10.1186/s12940-019-0449-7 
  • Conducting a study to assess the long-term impacts of injury after 9/11: Participation, recall, and description
    • The disaster of 9/11 resulted in over 2700 deaths and thousands injured. Being injured on 9/11 has been identified as a factor for physical and mental health conditions. However, the reasons for this are not well understood. An in-depth study on the impacts of injury on 9/11 was conducted to see what contributed to long-term health issues.
    • Jacobson, M. H., Brackbill, R. M., Frazier, P., & Gargano, L. M. (2019). Conducting a study to assess the long-term impacts of injury after 9/11: Participation, recall, and description. Injury Epidemiology, 6(1), 8. https://doi.org/10.1186/s40621-019-0186-y 

2018

  • Review of Non-Respiratory, Non-Cancer Physical Health Conditions from Exposure to the World Trade Center Disaster
    • A review of 30 studies examined physical health problems linked to exposure to the September 11 attacks, beyond breathing problems and cancer. Most studies focused on rescue and recovery workers and used data from three major health groups. Many findings were supported by health records and other clear measures. However, some less-studied conditions need more research. The review shows that long-term health studies are important for understanding the effects of 9/11 and improving treatment over time.
    • Gargano, L., Mantilla, K., Fairclough, M., Yu, S., & Brackbill, R. (2018). Review of Non-Respiratory, Non-Cancer Physical Health Conditions from Exposure to the World Trade Center Disaster. International Journal of Environmental Research and Public Health, 15(2), 253. https://doi.org/10.3390/ijerph15020253
  • Sampling Strategies in Overlapping Eligibility Groups of WTCHR Enrollees
    • Studies addressing specific research questions may necessitate selecting a random sample from different eligibility groups of the 9/11-exposed enrollees for estimating the population parameters. Sampling strategies are proposed and compared using overlapping eligibility groups of enrollees, in terms of their bias and efficiency.
    • Osahan, S. S. (2018). Sampling strategies for overlapping eligibility groups in the World Trade Center Health Registry. Model Assisted Statistics and Applications, 13(2), 133–140. https://doi.org/10.3233/MAS-180425

2017

  • The effectiveness of a monetary incentive offer on survey response rates and response completeness in a longitudinal study
    • Using the World Trade Center Health Registry’s Wave 4 survey data, this study evaluated the effectiveness of a monetary incentive in improving the response rate five months after survey launch, and assessed whether or not response completeness was compromised due to incentive use. We found that the likelihood of returning a survey increased by 30% for those who received an incentive offer (AOR=1.3, 95% CI: 1.1, 1.4), and the incentive increased the number of returned surveys by 18%. Moreover, our results did not reveal any significant differences on response completeness between those who received an incentive offer and those who did not. This study showed the value of offering a monetary incentive as an additional refusal conversion strategy.
    • Yu, S., Alper, H. E., Nguyen, A.-M., Brackbill, R. M., Turner, L., Walker, D. J., Maslow, C. B., & Zweig, K. C. (2017). The effectiveness of a monetary incentive offer on survey response rates and response completeness in a longitudinal study. BMC Medical Research Methodology, 17(1), 77. https://doi.org/10.1186/s12874-017-0353-1

2016

  • Gridlocked: The impact of adapting survey grids for smartphones
    • Paper and web surveys often include grid-style questions formatted to save space and avoid repetition. However, this format is often discouraged by methodologists because of data quality concerns, particularly when respondents are using small screens (e.g., smartphones). In the World Trade Center Health Registry’s Wave 4 survey, we used grids to maintain comparability with prior waves. However, due to the rising number of respondents using smartphones to complete web surveys, we used responsive web design programming to automatically reformat grids into a series of individual items when a small screen device was detected. This method allowed us to retain grids used in previous years, yet address the issue of grids displaying poorly on mobile devices. We compared indicators of data quality (e.g., missing data, straight-lining) across grid formats to see whether the smartphone-optimized version suggests poorer, equal, or better data quality than the traditional grid. We also compared consistency with data collected in previous waves of the survey. We found some evidence that the optimized grid format improved data quality, and the benefits we observed may even suggest that some variant of the mobile-optimized format should be considered for all devices, regardless of screen size.
    • Richards, A., Powell, R., Murphy, J., Nguyen, M., & Yu, S. (2016). Gridlocked: The impact of adapting survey grids for smartphones. Survey Practice, 9(3), 1–14. https://doi.org/10.29115/SP-2016-0016 

2015

  • Evaluation of Non-response Bias in a Cohort Study of World Trade Center Terrorist Attack Survivors
    • A study evaluating non-response bias found that, despite a downward bias in prevalence estimates of health outcomes, attrition from the World Trade Center Health Registry follow-up studies does not lead to serious bias in associations between 9/11 disaster exposures and key health outcomes. These findings provide insight into the impact of non-response on associations between disaster exposures and health outcomes reported in longitudinal studies.
    • Yu, S., Brackbill, R. M., Stellman, S. D., Ghuman, S., & Farfel, M. R. (2015). Evaluation of non-response bias in a cohort study of World Trade Center terrorist attack survivors. BMC Research Notes, 8(1), 42. https://doi.org/10.1186/s13104-015-0994-2
  • Relationship between persistent post-traumatic stress disorder and human remains exposure for Staten Island Barge and Landfill recovery and clean-up workers after 9/11
    • A study of 1,592 workers who helped with cleanup at the Fresh Kills landfill and nearby barges after 9/11 examined PTSD years later. Workers who had more frequent contact with human remains were more likely to have lasting PTSD 10–11 years later. Sanitation workers also had a higher risk than firefighters and police. People with less social support had a higher risk as well. The findings show the need for better support and protection during future disaster cleanup efforts.
    • Fairclough, M. A., Miller-Archie, S. A., & Tenzin Dechen, J. E. C. (2015). Relationship between Persistent Post-traumatic Stress Disorder and Human Remains Exposure for Staten Island Barge and Landfill Recovery and Clean-up Workers After 9/11. International Journal of Emergency Mental Health and Human Resilience, 17(3). https://doi.org/10.4172/1522-4821.1000261

2011

  • 9/11-Related experiences and tasks of landfill and barge workers: qualitative analysis from the World Trade Center Health Registry
    • This study looked at the experiences of people who helped clean up after 9/11. Twenty workers and volunteers shared their stories about moving and sorting debris, finding human remains, searching for evidence, and helping others with food and support. They were exposed to dust, fumes, and strong odors. Years later, many were frustrated that they had not been given enough information about the dangers. Some were also worried about their long-term health.
    • Ekenga, C. C., Scheu, K. E., Cone, J. E., Stellman, S. D., & Farfel, M. R. (2011). 9/11-Related Experiences and Tasks of Landfill and Barge Workers: Qualitative Analysis from the World Trade Center Health Registry. BMC Public Health, 11(1), 321. https://doi.org/10.1186/1471-2458-11-321 
  • Short-term and medium-term health effects of 9/11
    • A review of health studies after the September 11 attacks found strong links between 9/11 exposure and PTSD and breathing problems. People who had longer or more intense exposure had higher rates of illness and disability. Rescue and recovery workers who arrived early or worked longer were more likely to develop breathing problems. PTSD risk was also higher among people close to the site, those living or working in lower Manhattan, and those who lost loved ones or had little social support.
    • Perlman, S. E., Friedman, S., Galea, S., Nair, H. P., Erős-Sarnyai, M., Stellman, S. D., Hon, J., & Greene, C. M. (2011). Short-term and medium-term health effects of 9/11. The Lancet, 378(9794), 925–934. https://doi.org/10.1016/S0140-6736(11)60967-7
  • Health consequences of the World Trade Center disaster: a 10th anniversary perspective
    • Ten years after the September 11 attacks, researchers reviewed what was known about the health effects on survivors and responders. The attacks exposed hundreds of thousands of people to traumatic events and harmful conditions. Early efforts to study and treat these health problems faced many challenges. Over time, researchers found clear evidence of lasting health effects and developed better care for those affected. These findings also helped improve disaster planning and prepare for future emergencies.
    • Thorpe, L. E., & Friedman, S. (2011). Health Consequences of the World Trade Center Disaster: A 10th Anniversary Perspective. JAMA, 306(10), 1133. https://doi.org/10.1001/jama.2011.1289
  • The public health response to the World Trade Center attack and its aftermath by the New York City Department of Health and Mental Hygiene
    • A review of New York City’s response to the September 11 attacks examined the short- and long-term health challenges caused by the World Trade Center disaster. It looked at emergency response, changes to disaster planning, and long-term programs such as Project Liberty and the World Trade Center Health Registry. The experience improved how city health agencies prepare for and respond to emergencies. The findings also showed the value of cooperation between public health agencies during major disasters.
    • Weisfuse, I. B., Marsik, T., & Brackbill, R. M. (2011). The public health response to the World Trade Center attack and its aftermath by the New York City Department of Health and Mental Hygiene. In Terrorism and Public Health (pp. 43–66). Oxford University Press. https://stacks.cdc.gov/view/cdc/202533

2008

  • An Overview of 9/11 experiences and respiratory and mental health conditions among World Trade Center Health Registry enrollees
    • A report from the World Trade Center Health Registry followed 71,437 people who were exposed to the September 11 attacks to study the disaster’s long-term health effects. Two to three years later, 67% reported new or worsening breathing problems, 3% had developed asthma, and 16% showed signs of PTSD. The findings show that many people experienced lasting physical and mental health effects after the attacks, far beyond the immediate impact of the disaster.
    • Farfel, M., DiGrande, L., Brackbill, R., Prann, A., Cone, J., Friedman, S., Walker, D. J., Pezeshki, G., Thomas, P., Galea, S., Williamson, D., Frieden, T. R., & Thorpe, L. (2008). An Overview of 9/11 Experiences and Respiratory and Mental Health Conditions among World Trade Center Health Registry Enrollees. Journal of Urban Health, 85(6), 880–909. https://doi.org/10.1007/s11524-008-9317-4 

2007

  • Measuring and maximizing coverage in the World Trade Center Health Registry
    • A long-term health study was created to follow more than 71,000 people affected by the September 11 attacks. The study tracks the health of first responders, residents, workers, students, and others who were exposed to the disaster. By following these individuals over many years, the registry has helped experts understand the long-term health effects of 9/11. It has also improved public health research and helped strengthen disaster response efforts.
    • Murphy, J., Brackbill, R. M., Thalji, L., Dolan, M., Pulliam, P., & Walker, D. J. (2007). Measuring and maximizing coverage in the World Trade Center Health Registry. Statistics in Medicine, 26(8), 1688–1701. https://doi.org/10.1002/sim.2806