Rod Walker, MS, has developed a diverse research portfolio in his 10+ years working as a biostatistician at KPWHRI. His varied interests have led to collaborations in women's health, cancer, aging and geriatrics, pharmacoepidemiology, opioids research, and mental health. During his tenure he has served as an analyst for the Statistical Coordinating Center for the National Cancer Institute's Breast Cancer Surveillance Consortium, evaluated the impact of health system initiatives to reduce risk associated with chronic opioid therapy prescribing, and investigated potential associations between different medications classes and a wide range of outcomes such as pneumonia, fall-related injury, and dementia.
One of Mr. Walker’s longest-running collaborations is with the Adult Changes in Thought (ACT) study, an ongoing longitudinal cohort study seeking to bolster knowledge of risk factors related to dementia, Alzheimer's disease, and healthy aging. As this project and related studies have grown, he has contributed to analyses of associations between medication use and laboratory values and cognitive outcomes within this cohort of older adults, extended this research to associations with neuropathology measures among autopsied individuals, and helped process and analyze activity monitoring data generated from devices worn by ACT participants. Continued collaboration with ACT-related investigators is a highlight of his research at KPWHRI, as the ACT study provides many avenues for increasing public health knowledge of issues relevant for older adults.
A relatively new area of collaboration for Mr. Walker is with researchers from the Mental Health Research Network seeking to use information captured in electronic health records to predict risk of suicide attempt and suicide death. He has appreciated learning from other investigators and biostatisticians on this project, expanding his knowledge in machine learning and risk prediction, as well as in potential issues surrounding health informatics and implementation of tools into clinical workflows. He looks forward to continued opportunities within this research area to address important public health issues in mental and behavioral health.
Survival and longitudinal data analysis; epidemiology; machine learning; two-phase sampling
Biostatistics; cognitive health and dementia; neuropathologic correlates of dementia; factors associated with healthy aging
Biostatistics; suicide risk prediction; interventions for risk reduction; machine learning and health informatics
Biostatistics; pharmacoepidemiology; medication safety in older adults; opioids and chronic pain
Greenwood-Hickman MA, Walker R, Bellettiere J, LaCroix AZ, Kim B, Wing D, Richmire K, Crane PK, Larson EB, Rosenberg DE. Associations between perceived neighborhood walkability and device-based physical activity and sedentary behavior patterns in older adults. J Aging Phys Act. 2021 Aug 13:1-9. doi: 10.1123/japa.2020-0387. [Epub ahead of print]. PubMed
Coley RY, Walker RL, Cruz M, Simon GE, Shortreed SM. Clinical risk prediction models and informative cluster size: assessing the performance of a suicide risk prediction algorithm. Biom J. 2021 Oct;63(7):1375-1388. doi: 10.1002/bimj.202000199. Epub 2021 May 24. PubMed
Zaslavsky O, Yu O, Walker RL, Crane PK, Gray SL, Sadak T, Borson S, Larson EB. Incident dementia, glycated hemoglobin (HbA1c) levels and potentially preventable hospitalizations in people age 65 and older with diabetes. J Gerontol A Biol Sci Med Sci. 2021 Apr 29:glab119. doi: 10.1093/gerona/glab119. [Epub ahead of print]. PubMed
Walker RL, Greenwood-Hickman MA, Bellettiere J, LaCroix AZ, Wing D, Higgins M, Richmire K, Larson EB, Crane PK, Rosenberg DE. Associations between physical function and device-based measures of physical activity and sedentary behavior patterns in older adults: moving beyond moderate-to-vigorous intensity physical activity. BMC Geriatr. 2021 Mar 31;21(1):216. doi: 10.1186/s12877-021-02163-4. PubMed
Bellettiere J, Tuz-Zahra F, Carlson J, Ridgers ND, Liles S, Greenwood-Hickman MA, Walker RL, LaCroix AZ, Jankowska MM, Rosenberg DE, Natarajan L. Agreement of sedentary behaviour metrics derived from hip-worn and thigh-worn accelerometers among older adults: with implications for studying physical and cognitive health. J Meas Phys Behav. 4(1), 79-88. https://doi.org/10.1123/jmpb.2020-0036.
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