Jimmy T Efird
Biographic Data
| ID | 194431 |
|---|---|
| NAME | Jimmy T Efird |
| GIVEN NAMES | Jimmy T |
| FAMILY NAME | Efird |
| SIGNATURE | EFIRD J T |
| AFFILIATIONS | East Carolina University |
| ORCID | 0000-0002-4890-5111 |
| VERIFIED | Yes |
| TOTAL WORKS | 26 |
| TOTAL CITATIONS | 7 |
| AUTHOR COUNT | 26 |
| EDITOR COUNT | 0 |
| FIRST PUBLICATION YEAR | 2007 |
| LATEST PUBLICATION YEAR | 2025 |
| H-INDEX | 2 |
An Epidemiologic Approach for Estimating Risk Reduction and Asymptotic Power on the Log-Difference Scale
When comparing the efficacy or harmfulness of two groups (e.g., drugs, devices, assays, interventions, environmental toxins), it is important to minimize bias by making this comparison with respect to a common referent-control group, assuming random allocation. Under such a scenario, one can estimate risk reduction for a new therapy on a log-difference, relative effect scale. The current manuscript reviews the large-sample framework for this cond…
The Inverse Log-Rank Test: A Versatile Procedure for Late Separating Survival Curves
Often in the planning phase of a clinical trial, a researcher will need to choose between a standard versus weighted log-rank test (LRT) for investigating right-censored survival data. While a standard LRT is optimal for analyzing evenly distributed but distinct survival events (proportional hazards), an appropriately weighted LRT test may be better suited for handling non-proportional, delayed treatment effects. The "a priori" misspecification o…
Health-Related Quality of Life by Gulf War Illness Case Status
This study examines how health-related quality of life (HRQOL) and related indices vary by Gulf War illness (GWI) case status. The study population included veterans from the Gulf War Era Cohort and Biorepository (n = 1116). Outcomes were physical and mental health from the Veterans RAND 12 and depression, post-traumatic stress (PTSD), sleep disturbance, and pain. Kansas (KS) and Centers for Disease Control and Prevention (CDC) GWI definitions we…
Breast Cancer Disparities in Asian Women: The Need for Disaggregated Research
Asian (AZN) women are a heterogeneous group, comprising a wide array of cultural beliefs, languages, and healthcare needs. Yet, studies of breast cancer (BCa) risks and outcomes predominately consider AZNs in aggregate, assuming that the distinct ethnicities have similar disease profiles and homogeneous responses to treatment. This stereotypical portrayal of AZNs as a homogenous group tends to mask disparities. For example, healthcare-seeking beh…
A Pilot Study Examining the Prognostic Utility of Tumor Shrinkage on Cone-Beam Computed Tomography (CBCT) for Stage III Locally Advanced Non-Small Cell Lung Cancer Patients Treated with Definitive Che…
There has been growing interest in utilizing information from cone-beam computed tomography (CBCT) to help guide both treatment delivery and prognosis. In this assessment of locally advanced unresectable stage III non-small cell lung cancer (NSCLC) treated with definitive chemoradiation, we aimed to determine the survival advantage associated with using CBCT to measure tumor regression. Patient, tumor, and treatment characteristics were collected…
Covid-19-Associated Mortality in US Veterans with and without Sars-CoV-2 Infection
Age, BMI, smoking, and alcohol use disorder affect 30-day mortality in SARS-CoV-2-infected subjects differently from uninfected referents. Advanced age and overweight/obesity were associated with increased mortality risk among infected men, while current smoking and alcohol use disorder were associated with lower mortality risk among infected men, when compared with those uninfected
The Interaction of Vitamin D and Corticosteroids: A Mortality Analysis of 26,508 Veterans Who Tested Positive for Sars-CoV-2
This data-based cohort consisted of 26,508 (7%) United States veterans out of the 399,290 who tested positive for SARS-CoV-2 from 1 March to 10 September 2020. We aimed to assess the interaction of post-index vitamin D (Vit D) and corticosteroid (CRT) use on 30-day mortality among hospitalized and non-hospitalized patients with coronavirus disease 2019 (COVID-19). Combination Vit D and CRT drug use was assessed according to four multinomial pairs…
Using the Systemic Immune-Inflammation Index (SII) as a Mid-Treatment Marker for Survival among Patients with Stage-III Locally Advanced Non-Small Cell Lung Cancer (NSCLC)
The Systemic Immune-Inflammation Index (SII) is an important marker of immune function, defined as the product of neutrophil-to-lymphocyte ratio (NLR) and platelet count (P). Higher baseline SII levels have been associated with improved survival in various types of cancers, including lung cancer. Data were obtained from PROCLAIM, a randomized phase III trial comparing two different chemotherapy regimens pemetrexed + cisplatin (PEM) vs. etoposide …
A Pilot Study of Airborne Hazards and Other Toxic Exposures in Iraq War Veterans
During their deployment to Iraq in support of Operation Iraqi Freedom (OIF) , many Veterans were exposed to a wide array of toxic substances and psychologic stressors, most notably airborne/environmental pollutants from open burn pits. Service members do not deploy whilst unhealthy, but often they return with a multitude of acute and chronic symptoms, some of which only begin to manifest years after their deployment. Our findings, while prelimina…
Pathologic Complete Response (pCR) and Survival of Women with Inflammatory Breast Cancer (IBC): An Analysis Based on Biologic Subtypes and Demographic Characteristics
In this US-based study of the National Cancer Database (NCDB), we examined 8550 patients diagnosed with non-metastatic, invasive inflammatory breast cancer (IBC) who received surgery from 2004−2013. Patients were grouped into four biologic subtypes (HR+/HER 2 - , HR+/HER 2+ , HR - /HER 2+ , HR - /HER 2 - ). On average, women were 56 years of age at diagnosis and were followed for a median of 3.7 years. The majority were white (80%), had private h…
Using a Counting Process Method to Impute Censored Follow-Up Time Data
Censoring occurs when complete follow-up time information is unavailable for patients enrolled in a clinical study. The process is considered to be informative (non-ignorable) if the likelihood function for the model cannot be partitioned into a set of response parameters that are independent of the censoring parameters. In such cases, estimated survival time probabilities may be biased, prompting the need for special statistical methods to remed…
Factors Associated with Discharge to a Skilled Nursing Facility after Transcatheter Aortic Valve Replacement Surgery
An assumption regarding transcatheter aortic valve replacement (TAVR), a minimally invasive procedure for treating aortic stenosis, is that patients remain at, or near baseline and soon return to their presurgical home to resume activities of daily living. However, this does not consistently occur. The purpose of this study was to identify preoperative factors that optimally predict discharge to a skilled nursing facility (SNF) after TAVR. Deline…
Knowledge Management for Fostering Biostatistical Collaboration within a Research Network: The RTRN Case Study
Purpose : While the intellectual and scientific rationale for research collaboration has been articulated, a paucity of information is available on a strategic approach to facilitate the collaboration within a research network designed to reduce health disparities. This study aimed to (1) develop a conceptual model to facilitate collaboration among biostatisticians in a research network; (2) describe collaborative engagement performed by the Netw…
Residential Segregation and Racial Cancer Disparities: A Systematic Review
Trauma Affecting Asian-Pacific Islanders in the San Francisco Bay Area
Trauma is a transgenerational process that overwhelms the community and the ability of family members to cope with life stressors. An anthropologist trained in ethnographic methods observed three focus groups from a non-profit agency providing trauma and mental health services to Asian Americans living in the San Francisco Bay Area of United States. Supplemental information also was collected from staff interviews and notes. Many of the clients w…
Rural Shop-Based Health Program Planning: A Formative Research Approach Among Owners
Self-rated health, objective health, and racial discrimination among African-Americans: Explaining inconsistent findings and testing health pessimism
African-Americans sometimes rate their health as Poor/Fair in the absence of chronic diseases. Theoretically, this lack of correspondence between self-rated health and objective health is due to racial discrimination that results in rating one's health negatively and in terms of social rather than health variables. We tested this Health Pessimism model with 2118 African-Americans. Results revealed that Poor/Fair self-rated health was predicted mo…
Increased Long-Term Mortality among Black Cabg Patients Receiving Preoperative Inotropic Agents
The aim of this study was to examine racial differences in long-term mortality after coronary artery bypass grafting (CABG), stratified by preoperative use of inotropic agents. Black and white patients who required preoperative inotropic support prior to undergoing CABG procedures between 1992 and 2011 were compared. Mortality probabilities were computed using the Kaplan-Meier product-limit method. Hazard ratios (HR) and 95% confidence intervals …
Risk-Adjusted Survival after Coronary Artery Bypass Grafting: Implications for Quality Improvement
Mortality represents an important outcome measure following coronary artery bypass grafting. Shorter survival times may reflect poor surgical quality and an increased number of costly postoperative complications. Quality control efforts aimed at increasing survival times may be misleading if not properly adjusted for case-mix severity. This paper demonstrates how to construct and cross-validate efficiency-outcome plots for a specified time (e.g.,…
Racial Differences in Survival among Hemodialysis Patients after Coronary Artery Bypass Grafting
The aim of this study was to examine racial differences in long-term survival among hemodialysis patients after coronary artery bypass grafting (CABG). To our knowledge this has not been previously addressed in the literature. Black and white hemodialysis patients undergoing first-time, isolated CABG procedures between 1992 and 2011 were compared. Survival probabilities were computed using the Kaplan-Meier product-limit method and stratified by r…
Computing Power and Sample Size for Informational Odds Ratio
The informational odds ratio (IOR) measures the post-exposure odds divided by the pre-exposure odds (i.e., information gained after knowing exposure status). A desirable property of an adjusted ratio estimate is collapsibility, wherein the combined crude ratio will not change after adjusting for a variable that is not a confounder. Adjusted traditional odds ratios (TORs) are not collapsible. In contrast, Mantel-Haenszel adjusted IORs, analogous t…
Potential Risk Factors for Cutaneous Squamous Cell Carcinoma include Oral Contraceptives: Results of a Nested Case-Control Study
Recently, a population-based case-control study observed a 60% increased odds ratio (OR) for cutaneous squamous cell carcinoma (SCC) among women who had ever used oral contraceptives (OCs) compared with non users (95% confidence interval (CI) = 1.0-2.5). To further characterize the putative association between OC use and SCC risk, we conducted a nested case-control study using a large retrospective cohort of 111,521 Kaiser Permanente Northern Cal…
Blocked Randomization with Randomly Selected Block Sizes
When planning a randomized clinical trial, careful consideration must be given to how participants are selected for various arms of a study. Selection and accidental bias may occur when participants are not assigned to study groups with equal probability. A simple random allocation scheme is a process by which each participant has equal likelihood of being assigned to treatment versus referent groups. However, by chance an unequal number of indiv…
A Method to Model Season of Birth as a Surrogate Environmental Risk Factor for Disease
Environmental exposures, including some that vary seasonally, may play a role in the development of many types of childhood diseases such as cancer. Those observed in children are unique in that the relevant period of exposure is inherently limited or perhaps even specific to a very short window during prenatal development or early infancy. As such, researchers have investigated whether specific childhood cancers are associated with season of bir…
A Method to Compute Multiplicity Corrected Confidence Intervals for Odds Ratios and Other Relative Effect Estimates
Epidemiological studies commonly test multiple null hypotheses. In some situations it may be appropriate to account for multiplicity using statistical methodology rather than simply interpreting results with greater caution as the number of comparisons increases. Given the one-to-one relationship that exists between confidence intervals and hypothesis tests, we derive a method based upon the Hochberg step-up procedure to obtain multiplicity corre…
Self-rated health, objective health, and racial discrimination among African-Americans: Explaining inconsistent findings and testing health pessimism
African-Americans sometimes rate their health as Poor/Fair in the absence of chronic diseases. Theoretically, this lack of correspondence between self-rated health and objective health is due to racial discrimination that results in rating one's health negatively and in terms of social rather than health variables. We tested this Health Pessimism model with 2118 African-Americans. Results revealed that Poor/Fair self-rated health was predicted mo…
Epidemiologic and clinical factors associated with Chronic Kidney Disease among Asian Americans and Native Hawaiians
The occurrence of chronic kidney disease in the Hawai'i KEEP-2 study was nearly fourfold greater compared with the general US population. The clustering of susceptibility factors for chronic kidney disease occurrence was found to differ for all five ethnic groups
Rural Shop-Based Health Program Planning: A Formative Research Approach Among Owners
Epidemiologic and clinical factors associated with Chronic Kidney Disease among Asian Americans and Native Hawaiians
The occurrence of chronic kidney disease in the Hawai'i KEEP-2 study was nearly fourfold greater compared with the general US population. The clustering of susceptibility factors for chronic kidney disease occurrence was found to differ for all five ethnic groups
A Method to Model Season of Birth as a Surrogate Environmental Risk Factor for Disease
Environmental exposures, including some that vary seasonally, may play a role in the development of many types of childhood diseases such as cancer. Those observed in children are unique in that the relevant period of exposure is inherently limited or perhaps even specific to a very short window during prenatal development or early infancy. As such, researchers have investigated whether specific childhood cancers are associated with season of bir…
A Method to Compute Multiplicity Corrected Confidence Intervals for Odds Ratios and Other Relative Effect Estimates
Epidemiological studies commonly test multiple null hypotheses. In some situations it may be appropriate to account for multiplicity using statistical methodology rather than simply interpreting results with greater caution as the number of comparisons increases. Given the one-to-one relationship that exists between confidence intervals and hypothesis tests, we derive a method based upon the Hochberg step-up procedure to obtain multiplicity corre…
Potential Risk Factors for Cutaneous Squamous Cell Carcinoma include Oral Contraceptives: Results of a Nested Case-Control Study
Recently, a population-based case-control study observed a 60% increased odds ratio (OR) for cutaneous squamous cell carcinoma (SCC) among women who had ever used oral contraceptives (OCs) compared with non users (95% confidence interval (CI) = 1.0-2.5). To further characterize the putative association between OC use and SCC risk, we conducted a nested case-control study using a large retrospective cohort of 111,521 Kaiser Permanente Northern Cal…
Blocked Randomization with Randomly Selected Block Sizes
When planning a randomized clinical trial, careful consideration must be given to how participants are selected for various arms of a study. Selection and accidental bias may occur when participants are not assigned to study groups with equal probability. A simple random allocation scheme is a process by which each participant has equal likelihood of being assigned to treatment versus referent groups. However, by chance an unequal number of indiv…
Racial Differences in Survival among Hemodialysis Patients after Coronary Artery Bypass Grafting
The aim of this study was to examine racial differences in long-term survival among hemodialysis patients after coronary artery bypass grafting (CABG). To our knowledge this has not been previously addressed in the literature. Black and white hemodialysis patients undergoing first-time, isolated CABG procedures between 1992 and 2011 were compared. Survival probabilities were computed using the Kaplan-Meier product-limit method and stratified by r…
Computing Power and Sample Size for Informational Odds Ratio
The informational odds ratio (IOR) measures the post-exposure odds divided by the pre-exposure odds (i.e., information gained after knowing exposure status). A desirable property of an adjusted ratio estimate is collapsibility, wherein the combined crude ratio will not change after adjusting for a variable that is not a confounder. Adjusted traditional odds ratios (TORs) are not collapsible. In contrast, Mantel-Haenszel adjusted IORs, analogous t…
Risk-Adjusted Survival after Coronary Artery Bypass Grafting: Implications for Quality Improvement
Mortality represents an important outcome measure following coronary artery bypass grafting. Shorter survival times may reflect poor surgical quality and an increased number of costly postoperative complications. Quality control efforts aimed at increasing survival times may be misleading if not properly adjusted for case-mix severity. This paper demonstrates how to construct and cross-validate efficiency-outcome plots for a specified time (e.g.,…
Increased Long-Term Mortality among Black Cabg Patients Receiving Preoperative Inotropic Agents
The aim of this study was to examine racial differences in long-term mortality after coronary artery bypass grafting (CABG), stratified by preoperative use of inotropic agents. Black and white patients who required preoperative inotropic support prior to undergoing CABG procedures between 1992 and 2011 were compared. Mortality probabilities were computed using the Kaplan-Meier product-limit method. Hazard ratios (HR) and 95% confidence intervals …
Self-rated health, objective health, and racial discrimination among African-Americans: Explaining inconsistent findings and testing health pessimism
African-Americans sometimes rate their health as Poor/Fair in the absence of chronic diseases. Theoretically, this lack of correspondence between self-rated health and objective health is due to racial discrimination that results in rating one's health negatively and in terms of social rather than health variables. We tested this Health Pessimism model with 2118 African-Americans. Results revealed that Poor/Fair self-rated health was predicted mo…
Residential Segregation and Racial Cancer Disparities: A Systematic Review
Trauma Affecting Asian-Pacific Islanders in the San Francisco Bay Area
Trauma is a transgenerational process that overwhelms the community and the ability of family members to cope with life stressors. An anthropologist trained in ethnographic methods observed three focus groups from a non-profit agency providing trauma and mental health services to Asian Americans living in the San Francisco Bay Area of United States. Supplemental information also was collected from staff interviews and notes. Many of the clients w…
Rural Shop-Based Health Program Planning: A Formative Research Approach Among Owners
Using a Counting Process Method to Impute Censored Follow-Up Time Data
Censoring occurs when complete follow-up time information is unavailable for patients enrolled in a clinical study. The process is considered to be informative (non-ignorable) if the likelihood function for the model cannot be partitioned into a set of response parameters that are independent of the censoring parameters. In such cases, estimated survival time probabilities may be biased, prompting the need for special statistical methods to remed…
Factors Associated with Discharge to a Skilled Nursing Facility after Transcatheter Aortic Valve Replacement Surgery
An assumption regarding transcatheter aortic valve replacement (TAVR), a minimally invasive procedure for treating aortic stenosis, is that patients remain at, or near baseline and soon return to their presurgical home to resume activities of daily living. However, this does not consistently occur. The purpose of this study was to identify preoperative factors that optimally predict discharge to a skilled nursing facility (SNF) after TAVR. Deline…
Knowledge Management for Fostering Biostatistical Collaboration within a Research Network: The RTRN Case Study
Purpose : While the intellectual and scientific rationale for research collaboration has been articulated, a paucity of information is available on a strategic approach to facilitate the collaboration within a research network designed to reduce health disparities. This study aimed to (1) develop a conceptual model to facilitate collaboration among biostatisticians in a research network; (2) describe collaborative engagement performed by the Netw…
Pathologic Complete Response (pCR) and Survival of Women with Inflammatory Breast Cancer (IBC): An Analysis Based on Biologic Subtypes and Demographic Characteristics
In this US-based study of the National Cancer Database (NCDB), we examined 8550 patients diagnosed with non-metastatic, invasive inflammatory breast cancer (IBC) who received surgery from 2004−2013. Patients were grouped into four biologic subtypes (HR+/HER 2 - , HR+/HER 2+ , HR - /HER 2+ , HR - /HER 2 - ). On average, women were 56 years of age at diagnosis and were followed for a median of 3.7 years. The majority were white (80%), had private h…
Using the Systemic Immune-Inflammation Index (SII) as a Mid-Treatment Marker for Survival among Patients with Stage-III Locally Advanced Non-Small Cell Lung Cancer (NSCLC)
The Systemic Immune-Inflammation Index (SII) is an important marker of immune function, defined as the product of neutrophil-to-lymphocyte ratio (NLR) and platelet count (P). Higher baseline SII levels have been associated with improved survival in various types of cancers, including lung cancer. Data were obtained from PROCLAIM, a randomized phase III trial comparing two different chemotherapy regimens pemetrexed + cisplatin (PEM) vs. etoposide …
A Pilot Study of Airborne Hazards and Other Toxic Exposures in Iraq War Veterans
During their deployment to Iraq in support of Operation Iraqi Freedom (OIF) , many Veterans were exposed to a wide array of toxic substances and psychologic stressors, most notably airborne/environmental pollutants from open burn pits. Service members do not deploy whilst unhealthy, but often they return with a multitude of acute and chronic symptoms, some of which only begin to manifest years after their deployment. Our findings, while prelimina…
A Pilot Study Examining the Prognostic Utility of Tumor Shrinkage on Cone-Beam Computed Tomography (CBCT) for Stage III Locally Advanced Non-Small Cell Lung Cancer Patients Treated with Definitive Che…
There has been growing interest in utilizing information from cone-beam computed tomography (CBCT) to help guide both treatment delivery and prognosis. In this assessment of locally advanced unresectable stage III non-small cell lung cancer (NSCLC) treated with definitive chemoradiation, we aimed to determine the survival advantage associated with using CBCT to measure tumor regression. Patient, tumor, and treatment characteristics were collected…
Covid-19-Associated Mortality in US Veterans with and without Sars-CoV-2 Infection
Age, BMI, smoking, and alcohol use disorder affect 30-day mortality in SARS-CoV-2-infected subjects differently from uninfected referents. Advanced age and overweight/obesity were associated with increased mortality risk among infected men, while current smoking and alcohol use disorder were associated with lower mortality risk among infected men, when compared with those uninfected
The Interaction of Vitamin D and Corticosteroids: A Mortality Analysis of 26,508 Veterans Who Tested Positive for Sars-CoV-2
This data-based cohort consisted of 26,508 (7%) United States veterans out of the 399,290 who tested positive for SARS-CoV-2 from 1 March to 10 September 2020. We aimed to assess the interaction of post-index vitamin D (Vit D) and corticosteroid (CRT) use on 30-day mortality among hospitalized and non-hospitalized patients with coronavirus disease 2019 (COVID-19). Combination Vit D and CRT drug use was assessed according to four multinomial pairs…
Health-Related Quality of Life by Gulf War Illness Case Status
This study examines how health-related quality of life (HRQOL) and related indices vary by Gulf War illness (GWI) case status. The study population included veterans from the Gulf War Era Cohort and Biorepository (n = 1116). Outcomes were physical and mental health from the Veterans RAND 12 and depression, post-traumatic stress (PTSD), sleep disturbance, and pain. Kansas (KS) and Centers for Disease Control and Prevention (CDC) GWI definitions we…
Breast Cancer Disparities in Asian Women: The Need for Disaggregated Research
Asian (AZN) women are a heterogeneous group, comprising a wide array of cultural beliefs, languages, and healthcare needs. Yet, studies of breast cancer (BCa) risks and outcomes predominately consider AZNs in aggregate, assuming that the distinct ethnicities have similar disease profiles and homogeneous responses to treatment. This stereotypical portrayal of AZNs as a homogenous group tends to mask disparities. For example, healthcare-seeking beh…
The Inverse Log-Rank Test: A Versatile Procedure for Late Separating Survival Curves
Often in the planning phase of a clinical trial, a researcher will need to choose between a standard versus weighted log-rank test (LRT) for investigating right-censored survival data. While a standard LRT is optimal for analyzing evenly distributed but distinct survival events (proportional hazards), an appropriately weighted LRT test may be better suited for handling non-proportional, delayed treatment effects. The "a priori" misspecification o…
Medicine (21 works) · Internal Medicine (14 works) · Confidence interval (9 works) · Mathematics (7 works) · Statistics (7 works) · Computer Science (6 works) · Demography (6 works) · Environmental health (6 works) · Statistical Methods in Clinical Trials (6 works) · Advanced Causal Inference Techniques (5 works)