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Biostatistician 3, Stanford-Surgery Policy Improvement Research & Education Ctr, Stanford-Surgery Policy Improvement Research and Education Center


Amber W. Trickey, PhD, MS, CPH, is Senior Biostatistician of the S-SPIRE Center. She supports multidisciplinary teams in research design, implementation, and analysis. In over 15 years of health services research, with 10 years focused in surgery and emergency medicine, Dr. Trickey has collaborated with diverse investigators, including attending physicians, residents, nurses, psychologists, and engineers. Dr. Trickey obtained degrees in epidemiology and biostatistics, and certifications in public health and SAS data analysis. She has evaluated data quality in surgical and trauma care, supported multiple clinical trials, and led data validation studies using the ACS-NSQIP surgical registry and administrative claims. Dr. Trickey has contributed to public and private grants on surgical safety, healthcare quality metrics, simulation-based training, team communication, error disclosure, and emergency services.


  • Racial disparities in the utilization of parathyroidectomy among patients with primary hyperparathyroidism: Evidence from a nationwide analysis of Medicare claims. Surgery Alobuia, W. M., Meng, T., Cisco, R. M., Lin, D. T., Suh, I., Tamura, M. K., Trickey, A. W., Kebebew, E., Seib, C. D. 2021


    BACKGROUND: Among patients with primary hyperparathyroidism, parathyroidectomy offers a chance of cure and mitigation of disease-related complications. The impact of race/ethnicity on referral and utilization of parathyroidectomy has not been fully explored.METHODS: Population-based, retrospective cohort study using 100% Medicare claims from beneficiaries with primary hyperparathyroidism from 2006 to 2016. Associations of race/ethnicity with disease severity, surgeon evaluation, and subsequent parathyroidectomy were analyzed using adjusted multivariable logistic regression models.RESULTS: Among 210,206 beneficiaries with primary hyperparathyroidism, 63,136 (30.0%) underwent parathyroidectomy within 1 year of diagnosis. Black patients were more likely than other races/ethnicities to have stage 3 chronic kidney disease (10.8%) but had lower prevalence of osteoporosis and nephrolithiasis compared to White patients, Black and Hispanic patients were more likely to have been hospitalized for primaryhyperparathyroidism-associated conditions (White 4.8%, Black 8.1%, Hispanic 5.8%; P < .001). Patients who were White and met operative criteria were more likely to undergo parathyroidectomy than Black, Hispanic, or Asian patients (White 30.5%, Black 23.0%, Hispanic 21.4%, Asian 18.7%; P < .001). Black and Hispanicpatients had lower adjusted odds of being evaluated by a surgeon (odds ratios 0.71 [95% confidenceinterval 0.69-0.74], 0.68 [95% confidence interval 0.61-0.74], respectively) and undergoing parathyroidectomy if evaluated by a surgeon (odds ratios 0.72 [95% confidence interval 0.68-0.77], 0.82 [95%confidence interval 0.67-0.99]). Asian race was associated with lower adjusted odds of being evaluated by a surgeon (odds ratio 0.64 [95% confidence interval 0.57-0.71]), but no difference in odds of parathyroidectomy.CONCLUSION: Racial/ethnic disparities exist in the management of primary hyperparathyroidism among older adults. Determining the factors that account for this disparity require urgent attention to achieve parity in the management of primary hyperparathyroidism.

    View details for DOI 10.1016/j.surg.2021.05.037

    View details for PubMedID 34229901

  • Association of parathyroidectomy with 5-year clinically significant kidney stone events in patients with primary hyperparathyroidism. Endocrine practice : official journal of the American College of Endocrinology and the American Association of Clinical Endocrinologists Seib, C. D., Ganesan, C., Arnow, K. D., Suh, I., Pao, A. C., Leppert, J. T., Tamura, M. K., Trickey, A. W., Kebebew, E. 2021


    OBJECTIVE: Patients with primary hyperparathyroidism (PHPT) are at increased risk of kidney stones. Guidelines recommend parathyroidectomy in PHPT patients with a history of stone disease. This study aimed to compare the 5-year incidence of clinically significant kidney stone events in patients with PHPT treated with parathyroidectomy vs. non-operative management.METHODS: We performed a longitudinal cohort study of patients with PHPT in a national commercial insurance claims database (2006-2019). Propensity score inverse probability weighting-adjusted multivariable regression models were calculated.RESULTS: We identified 7,623 patients ≥35 years-old with continuous enrollment >1 year before and >5 years after PHPT diagnosis. 2,933 patients (38.5%) were treated with parathyroidectomy. The cohort had a mean age of 66.5 years, 78.1% were female, 72.4% were White. Over 5 years, the unadjusted incidence of ≥1 kidney stone event was higher in patients managed with parathyroidectomy compared to those managed non-operatively overall (5.4% vs. 4.1%) and among those with a history of kidney stones at PHPT diagnosis (17.9% vs. 16.4%). On multivariable analysis, parathyroidectomy was associated with no statistically significant difference in the odds of 5-year kidney stone event among patients with a history of kidney stones (OR 1.03, 95%CI 0.71-1.50) or those without history of kidney stones (OR 1.16, 95%CI 0.84-1.60).CONCLUSION: Based on this claims analysis, there was no difference in the odds of 5-year kidney stone events in PHPT patients treated with parathyroidectomy vs. non-operative management. Time-horizon for benefit should be considered when making treatment decisions for PHPT based on risk of kidney stone events.

    View details for DOI 10.1016/j.eprac.2021.06.004

    View details for PubMedID 34126246

  • Association of Cumulative Social Risk and Social Support With Receipt of Chemotherapy Among Patients With Advanced Colorectal Cancer. JAMA network open Davis, R. E., Trickey, A. W., Abrahamse, P., Kato, I., Ward, K., Morris, A. M. 2021; 4 (6): e2113533


    Importance: Approximately 38% of patients with advanced colorectal cancer do not receive chemotherapy.Objective: To determine whether cumulative social risk (ie, multiple co-occurring sociodemographic risk factors) is associated with lower receipt of chemotherapy among patients with advanced colorectal cancer and whether social support would moderate this association.Design, Setting, and Participants: This cross-sectional, population-based, mailed survey study was conducted from 2012 to 2014. Participants were recruited between 2011 and 2014 from all adults within 1 year after diagnosis of stage III colorectal cancer in the Detroit, Michigan, and State of Georgia Surveillance, Epidemiology, End-Results cancer registries. Patients were eligible if they were aged 18 years or older, had undergone surgery 4 or more months ago, did not have stage IV cancer, and resided in the registry catchment areas. Data analyses were conducted from March 2017 to April 2021.Main Outcomes and Measures: The primary outcome was receipt of chemotherapy. Cumulative social risk represented a sum of 8 risk factors with the potential to drain resources from participants' cancer treatment (marital status, employment, annual income, health insurance, comorbidities, health literacy, adult caregiving, and perceived discrimination). Social support was operationalized as emotional support related to colorectal cancer diagnosis.Results: Surveys were mailed to 1909 eligible patients; 1301 completed the survey (response rate, 68%). A total of 1087 participants with complete data for key variables were included in the sample (503 women [46%]; mean [SD] age, 64 [13] years). Participants with 3 or more risk factors were less likely to receive chemotherapy than participants with 0 risk factors (3 factors, odds ratio [OR], 0.48 [95% CI, 0.26-0.87]; 4 factors, OR, 0.41 [95% CI, 0.21-0.78]; 5 factors, OR, 0.42 [95% CI, 0.20-0.87]; ≥6 factors, OR, 0.22 [95% CI, 0.09-0.55]). Participants with 2 or more support sources had higher odds of undergoing chemotherapy than those without social support (2 sources, OR, 3.05 [95% CI, 1.36-6.85]; 3 sources, OR, 3.24 [95% CI, 1.48-7.08]; 4 sources, OR, 3.69 [95% CI, 1.71-7.97]; 5 sources, OR, 4.40 [95% CI, 1.98-9.75]; ≥6 sources, OR 5.95 [95% CI, 2.58-13.74]). Within each social support level, participants were less likely to receive chemotherapy as cumulative social risk increased.Conclusions and Relevance: Cumulative social risk was associated with reduced receipt of chemotherapy. These associations were mitigated by social support. Assessing cumulative social risk may identify patients with colorectal cancer who are at higher risk for omitting chemotherapy who can be targeted for support programs to address social disadvantage and increase social support.

    View details for DOI 10.1001/jamanetworkopen.2021.13533

    View details for PubMedID 34106262

  • Gender Disparity in Surgical Society Leadership and Annual Meeting Programs. The Journal of surgical research Tirumalai, A. A., George, E. L., Kashikar, A., Langston, A. H., Rothenberg, K. A., Barreto, N. B., Trickey, A. W., Arya, S. 2021; 266: 69-76


    INTRODUCTION: Prior work suggests women surgical role models attract more female medical students into surgical training. We investigate recent trends of women in surgical society leadership and national conference moderator and plenary speaker roles.METHODS: Gender distribution was surveyed at 15 major surgical societies and 14 conferences from 2014 to 2018 using publicly reported data. Roles were categorized as leadership (executive council), moderator, or plenary speaker. Data were cross-checked from online profiles and by contacting societies. Logistic regression with Huber-White clustering by society was utilized to evaluate proportions of women in each role over time and determine associations between the proportion of women in executive leadership, and scientific session moderators and plenary speakers.RESULTS: The proportion of leadership positions held by women increased slightly from 2014 to 2018 (20.6%-26.6%, P = 0.23), as did the proportion of moderators (26.2%-30.6%, P = 0.027) and plenary speakers (26.2%-30.9%, P = 0.058). The proportion of women in each role varied significantly across societies (all P < 0.001): leaders (range 0.0%-52.0%), moderators (12.5%-58.8%), and plenary speakers (11.3%-60.0%). Three patterns of change were observed: eight societies (53.3%) demonstrated increases in representation of women over time, four societies (26.6%) showed stable moderate-to-good gender balance, and three societies (20.0%) had consistent underrepresentation of women.CONCLUSION: There is significant variability in the representation of women at the leadership level of national surgical societies and participating at national surgical conferences as moderators and plenary speakers. Over the past 5 years some societies have achieved advances in gender equity, but many societies still have substantial room for improvement.

    View details for DOI 10.1016/j.jss.2021.02.023

    View details for PubMedID 33984733

  • Patient-reported distress and age-related stress biomarkers among colorectal cancer patients. Cancer medicine Eddington, H. S., McLeod, M., Trickey, A. W., Barreto, N., Maturen, K., Morris, A. M. 2021


    OBJECTIVE: Distress among cancer patients has been broadly accepted as an important indicator of well-being but has not been well studied. We investigated patient characteristics associated with high distress levels as well as correlations among measures of patient-reported distress and "objective" stress-related biomarkers among colorectal cancer patients.METHODS: In total, 238 patients with colon or rectal cancer completed surveys including the Distress Thermometer, Problem List, and the Hospital Anxiety and Depression Scale. We abstracted demographic and clinical information from patient charts and determined salivary cortisol level and imaging-based sarcopenia. We evaluated associations between patient characteristics (demographics, clinical factors, and psychosocial and physical measures) and three outcomes (patient-reported distress, cortisol, and sarcopenia) with Spearman's rank correlations and multivariable linear regression. The potential moderating effect of age was separately investigated by including an interaction term in the regression models.RESULTS: Patient-reported distress was associated with gender (median: women 5.0, men 3.0, p<0.001), partnered status (single 5.0, partnered 4.0, p=0.018), and cancer type (rectal 5.0, colon 4.0, p=0.026); these effects varied with patient age. Cortisol level was associated with "emotional problems" (rho=0.34, p=0.030), anxiety (rho=0.046, p=0.006), and depression (rho=0.54, p=0.001) among younger patients. We found no significant associations between patient-reported distress, salivary cortisol, and sarcopenia.CONCLUSIONS: We found that young, single patients reported high levels of distress compared to other patient groups. Salivary cortisol may have limited value as a cancer-related stress biomarker among younger patients, based on association with some psychosocial measures. Stress biomarkers may not be more clinically useful than patient-reported measures in assessing distress among colorectal cancer patients.

    View details for DOI 10.1002/cam4.3914

    View details for PubMedID 33932256


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