Scholarships

Economic and social reforms in Vietnam had huge impact on its previously completely subsidized health care system by introducing user fees, privatizing medical practices and liberalizing pharmaceutical policies. The most significant result were higher health expenditure paid out-of-pocket by users and lower consumption of essential services among high need groups.

To deal with these problems, the government introduced a health insurance system in 1992, consisting of mandatory and voluntary schemes for different target population. By mid 2002, the system has enrolled a total of 12.6 million individuals, roughly 16% of the total population.

It was expected that the system would lower private health expenditure and thus improve equity and social welfare. If this was indeed the case, insurance coverage that resulted in a reduction in health care expenditure should have also resulted in a proportionally larger increase in utilization among the lower-income individuals. The current research project is set to test such expectations by answering the following three questions about health insurance affiliation and health care utilization: 1) Were insured patients more likely to seek medical care vs. self-treatment than the uninsured when fell ill? 2) Among individuals that experienced illness and used medical services, were insured patients more likely to use services from public providers vs. private providers than uninsured patients? 3) Were insured individuals more likely to use preventive service than the uninsured?

Methods

The proposed project will use data from the Vietnam National Health Survey (VNHS, 2001 ~ 2002), which included 36,000 households (158019 individuals) with household information as well as individual health status, health insurance affiliation and health utilization information.

Health care utilization will be set as a binary depend variable for each research question with health insurance affiliation set as a primary independent variable, adjusting for other individual, household and community variables such as age, gender, household wealth quintile and rural/urban status. Interaction between health insurance affiliation and household wealth quintile will be investigated as it pertains to the research aims.

Two special methodological issues arise when modeling the outcome of health care utilization against health insurance affiliation. The first and most important one is selection bias. There could have been immeasurable factors affecting both individual’s self-selection of health insurance affiliation and his/her choice of health care utilization when ill. Such bias is also known as “endogeneity” in econometrics terms. To correct for the selection bias issue, instrumental variables will be identified and used in the modeling process. For each research question, a bivariate probit estimation will be fitted simultaneously on a primary equation using utilization as an outcome and a secondary equation using health insurance affiliation as an outcome, incorporating some instrumental variables in the secondary equation. If the bivariate probit regression does identify correlation between the error terms of the primary and secondary equations, selection bias is then confirmed and, by virtue of the bivariate probit process, corrected at the same time. The second issue is the clustering of observations. Individuals within the same household were clustered and correlated in some way, instead of independent, as assumed by ordinary regression methods. The same is true for households within the same community. This gives rise to correlation among the error terms of the regression equations, which will result in incorrect estimation of the variances of regression coefficients. To correct for such correlation, the Huber-White “sandwich” variance estimator will be used. The estimator estimates coefficient variances by maximum likelihood and allows for unspecified correlation structure within clusters and sub-clusters and therefore works in the settings of the current study.

All statistical procedures will be carried out using STATA 8.0 package.

Significance

The proposed research project should be able to confirm (or disprove) the expected effects of health insurance programs, especially in the perspective of social welfare and equity. Lower-income individuals often had larger unmet needs for health care services, therefore a larger positive impact from enrolling into a health insurance program on this group would improve social welfare and equity in health care services and resource allocation. The study would also generate policy implications such as indications for insurance program modification in terms of public/private provider access and preventive care incentives.

Moreover, there is very limited information on the impact of public health insurance programs on health care utilization in Vietnam and other developing countries in south-east Asia. This study develops and uses methodologies for evaluating program effectiveness using household survey data and therefore serves as a basis for future researches in the field.

Allocation of expenses by category

Category	Item	Amount
Data collection	Purchase of raw data	$100
Equipment and environment	STATA 8.0 package upgrade	$100
	Computer hardware upgrade	$550

Additional funding

There is no additional funding for this project.

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Judith Easterbook, PhD candidate in Molec. Microbio. & Imm. - Regulatory T Cells Mediating Seoul Virus Persistence in Norway Rats

The Role of Regulatory T Cells in Mediating Seoul Virus Persistence in Norway Rats

Rationale

Hantaviruses are noncytopathic and cause two diseases in humans, hantavirus pulmonary syndrome (HPS) and hemorrhagic fever with renal syndrome (HFRS). Human pathology is hypothesized to be caused by sustained, elevated levels of proinflammatory cytokines (5). Hantaviruses are transmitted by rodents and each hantavirus has coevolved with a specific rodent host. In contrast to humans, hantaviruses infect their rodent hosts and cause persistent infection in the absence of pathology. The mechanisms mediating hantavirus persistence in rodents are unknown, but may involve suppression of host proinflammatory immune responses. My data illustrate that production of IL-1β in the spleen is suppressed during persistent Seoul virus infection in Norway rats (Rattus norvegicus), the natural rodent host for this species of hantavirus (3). Mechanisms mediating suppression of IL-1β remain unknown.
Regulatory T cells can suppress proinflammatory responses to infection as well as contribute to persistence of a number of pathogens (7). Regulatory T cells are currently characterized by the surface markers CD4 and CD25 and the intracellular marker forkhead box p3 (foxp3). These cells constitute approximately 5-10% of peripheral CD4+ T cells (9) and activity is primarily through local production of anti-inflammatory mediators, including IL-10 and TGF-β (2). During Leishmania infection in mice, regulatory T cells are recruited to suppress proinflammatory T cell responses, which prevents the host from eliminating the parasite. The host, however, displays minimal pathology and remains immune to reinfection due to the regulatory T cells remaining at the site of infection (1). Following administration of anti-CD25 antibodies, Leishmania parasites are cleared, but the host suffers immune-mediated pathology and is susceptible to subsequent reinfection (1). The balance between effector and regulatory T cells seems to reflect an evolutionary compromise between survival of the host and survival of the pathogen. The ultimate goal of my proposed experiments is to assess the role of regulatory T cells in mediating Seoul virus persistence and preventing pathology in Norway rats.

Methods: Experiment 1

Mouse anti-rat CD25 IgG monoclonal antibody (mAb) will be produced by the cell line NDS-63 (Dr. Kathryn Wood, Oxford, UK) in supplemented medium using the hollow fiber system at the JHU Core Cell Center. The antibody will be purified using a Protein G column and adjusted to a 4 mg/ml solution.
An appropriate dose of anti-CD25 antibody and time course for administration will be determined in Experiment 1. Recent data has revealed that administration of anti-CD25 mAb results in shedding of CD25 from the cell surface, not depletion of the regulatory T cell population, which was the current dogma (6). Because regulatory T cell activity is dependent on CD25, administration of anti-CD25 mAb causes functional suppression (11). Efficiency of regulatory T cell depletion of CD25 from CD4+foxp3+ regulatory T cells following administration of anti-CD25 mAb has not been determined in rats. One study used what is considered to be a less effective antibody against rat CD25 as compared with NDS-63 (i.e. OX-39) (10) and achieved a 33% depletion of CD25 on the surface of CD4+ T cells measured one week after a single intraperitoneal (i.p.) injection of 1 mg/rat anti-CD25 mAb; measurements, however, were not made at earlier time points (4). Studies in mice report almost complete CD25 depletion from CD4+ T cells (>80%) up to 10 days following administration of a single i.p. injection of 400 μg/mouse of anti-CD25 mAb (8). The doses of anti-rat CD25 mAb that I propose to test are based on available data from rats and mice, as well as personal communication with Dr. Yasmine Belkaid, an expert in regulatory T cells.
In Experiment 1, rats will not be inoculated with Seoul virus, but the days for sample collection will correspond with the days for sample collection during an infection experiment (i.e. 0 days post inoculation (p.i.) as uninfected, 7 days p.i. during the acute phase of infection, and 30 days p.i. during the persistent phase of infection). Adult male Long Evans rats (Rattus norvegicus) rats will be housed individually in polypropylene cages covered with polyester filter bonnets in a pathogen-free animal facility with food and water available ad libitum. Animals will be maintained on a constant 14:10 light:dark cycle with lights on at 0600 hours Eastern Standard Time, constant temperature (21±2ºC), and constant humidity (50±5%). All procedures have been approved by the JH ACUC (protocol #RA04H338).
Rats will be anaesthetized with isofluorane vapors and injected i.p. with 1 or 2 mg/rat of anti-CD25 mAb (N = 10/dose) or vehicle alone (N = 10) at Experimental Day -1 and at Experimental Day 1. On Experimental Days 10 and 20, the Experimental Day 30 rats will be injected i.p. with the same dose of anti-rat CD25 mAb to maintain CD25+ T cell depletion. On Experimental Days 7 and 30, rats administered the anti-CD25 antibody (N = 5/dose/time point) and rats administered vehicle alone (N = 5/time point) will be euthanized by using CO2 (Figure 1).

Figure 1. Time line for the administration of anti-CD25 mAb and sample collection

Because regulatory T cells act locally at the site of infection, I will not only collect the spleen, which is a secondary lymphoid organ with low Seoul virus replication, but also the lung, which is a primary site of Seoul virus replication. Following lymphocyte separation using a Lympholyte density gradient, CD4+ cells will be enriched by MACS. Regulatory T cells will be fluorescently labeled using antibodies against CD4, CD25, and intracellular foxp3 and fluorescent staining will be measured by FACS and analyzed using FlowJo software. Because administration of anti-CD25 mAb has been reported to induce shedding of CD25 from the cell surface, not only will conventional markers (CD4+CD25+foxp3+) be used to characterize the functional regulatory T cell populations, but also CD4+CD25-foxp3+ staining will be included to characterize the functionally inactive regulatory T cell population that has shed CD25 in response to anti-CD25 mAb administration.
After an appropriate dose and time course for administration have been determined to effectively deplete functional regulatory T cells, I will begin Experiment 2. In Experiment 2, I will monitor pathology and immune responses in rats that are uninfected or infected with Seoul virus and subsequently administered anti-CD25 mAb or vehicle alone. If regulatory T cells suppress antiviral effector responses to mediate Seoul virus persistence, I hypothesize that the CD4+CD25+ regulatory T cell population will be greater in persistently infected rats (i.e. at Day 30 p.i.) in tissues that support high virus replication (i.e. lungs) as compared with uninfected rats (i.e. at Day 0 p.i.) or during the acute phase of infection (i.e. Day 7 p.i.). Additionally, production of anti-inflammatory cytokines, including IL-10 and TGF-β, should be elevated and production of pro-inflammatory cytokines, including IL-1β and IFN-γ, should be reduced or at baseline in persistently infected as compared with uninfected or acutely infected rats. To further test the hypothesis that regulatory T cells mediate Seoul virus persistence, if the CD4+CD25+ population is depleted, rats should display proinflammatory cytokine-mediated pathology in target tissues following Seoul virus inoculation.

References

1. Belkaid, Y., C. A. Piccirillo, S. Mendez, E. M. Shevach, and D. L. Sacks. 2002. CD4(+)CD25(+) regulatory T cells control Leishmania major persistence and immunity. Nature 420:502-507.
2. Belkaid, Y., and B. T. Rouse. 2005. Natural regulatory T cells in infectious disease. Nature Immunology 6:353-360.
3. Easterbrook, J. D., and S. L. Klein. submitted. Proinflammatory and anti-inflammatory responses are suppressed during elevated Seoul virus replication in male Norway rats. Journal of Virology.
4. Ghiringhelli, F., N. Larmonier, E. Schmitt, A. Parcellier, D. Cathelin, C. Garrido, B. Chauffert, E. Solary, B. Bonnotte, and F. Martin. 2004. CD4(+)CD25(+) regulatory T cells suppress tumor immunity but are sensitive to cyclophosphamide which allows immunotherapy of established tumors to be curative. European Journal of Immunology 34:336-344.
5. Khaiboullina, S. F., and S. C. St Jeor. 2002. Hantavirus immunology. Viral Immunology 15:609-625.
6. Kohm, A. P., McMahon JS, Podojil JR, Begolka WS, DeGutes M, Kasprowicz, Ziegler SF, Miller SD. 2006. Cutting edge: Anti-CD25 monoclonal antibody injection results in the functional inactivation, not depletion, of CD4+CD25+ T regulatory cells. Journal of Immunology:3301-3305.
7. Mills, K. H. G. 2004. Regulatory T cells: Friend or foe in immunity to infection? Nature Reviews Immunology 4:841-855.
8. Morgan, M. E., R. P. M. Sutmuller, H. J. Witteveen, L. M. van Duivenvoorde, E. Zanelli, C. J. M. Melief, A. Snijders, R. Offringa, R. R. P. de Vries, and R. E. M. Toes. 2003. CD25+cell depletion hastens the onset of severe disease in collagen-induced arthritis. Arthritis and Rheumatism 48:1452-1460.
9. Sakaguchi, S. 2003. Regulatory T cells: mediating compromises between host and parasite. Nature Immunology 4:10-11.
10. Tellides, G., M. J. Dallman, and P. J. Morris. 1989. Mechanism of action of Interleukin-2 receptor monoclonal antibody therapy: target cell depletion or inhibition of function? Transplantation Proceedings 21:997-998.
11. Thornton, A. M., E. E. Donovan, C. A. Piccirillo, and E. M. Shevach. 2004. Cutting edge: IL-2 is critically required for the in vitro activation of CD4(+)CD25(+) T cell suppressor function. Journal of Immunology 172:6519-6523.

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Gabrielle Hunter, MHS candidate in International Health - Effects of Water Availability and Education on the Hygiene Behavior of Residents in a Peri-Urban Community in Lima, Peru

The Effects of Water Availability and Education on the Hygiene Behavior of Residents in a Peri-Urban Community in Lima, Peru

Introduction: Importance & Goals

The scarcity of water in conjunction with a lack of proper hygiene practices continues to result in infection and the spread of diarrheal diseases, a major cause of infant mortality in developing countries. As a result, developing countries face the challenge of creating feasible, multi-faceted solutions to reduce the prevalence of these diseases.

A recently published study conducted in Las Pampas de San Juan de Miraflores, a shantytown approximately 15 kilometers south of Central Lima, revealed that inadequate water and sanitation conditions increased the risk of diarrhea. Lima is located in a desert, and as such water is a particularly scarce resource in the shantytowns, known as pueblo jovenes, surrounding the city. The results of an earlier study in these communities revealed that providing information about hygiene without increasing the availability of water will not result in better sanitation practices, and that, in water-scarce communities, hygiene practices could be improved with the provision of convenient, cheap, in-house water. Hygiene promotion can also improve behaviors, and accordingly hygiene promotion is now recognized as an essential component of water and sanitation programs if maximum health benefits are to be achieved.

In 2004, an open, longitudinal research project was begun in Las Pampas de San Juan de Miraflores to determine if and how the quantity of water available, before and after the installation of at-home water connections, affects water usage and personal hygiene behaviors. Such an understanding of the elements that control water handling practices could increase the benefits of infrastructural installation, as well as the implementation of educational programs that aim to better existing conditions and perceptions of water usage. The results of the study at this point have revealed for example that, prior to the installation of at-home water connections, only 11% of defecation events of mothers were followed by handwashing with soap and that more than half of their defecation events were not followed by any form of handwashing. Further information on hygiene behavior, subsequent to the installation of water connections, is currently being collected.

Proposed here is the design, implementation and evaluation of the final stage of the project: a participatory hygiene education intervention. The proposed research project is an attempt to determine if personal hygiene behaviors can be improved through a hygiene promotion intervention, once an at-home water connection is made available. These results will help to interpret and evaluate future interventions relating to water and its usage.

The specific goals of the proposed project are t
1) Determine if a participatory educational intervention following an increase in affordable, convenient water supply can improve personal hygiene behaviors in a peri-urban community in Lima, Peru.
2) Develop, through community participation, a hygiene education and promotion program
3) Improve personal hygiene behaviors of residents in the community.
4) Foster community empowerment, cohesion and collective action in this disenfranchised setting.

Methods

The primary population for this research project are the residents of Manuel Scorza, a community located in the outskirts of Las Pampas de San Juan de Miraflores. This community has just recently received water and sanitation systems, and residents participated in the installation of these systems.

In earlier stages, baseline information was collected through three days of 12-hour continuous monitoring of hygiene behaviors and water usage in residents’ homes before the installation of at-home water and sewage connections. Observations were repeated again the following year, several months after the connections had been activated. This project will begin by employing formative qualitative and quantitative research techniques to understand and interpret findings from these earlier stages of the project; these results will then be shared with community residents in order to facilitate a collaborative effort to develop the form and message of the hygiene-behavior educational intervention. The impact of this hygiene intervention will then be evaluated through continuous monitoring structured observations in order to gather information on the actual change in personal behaviors due to the hygiene promotion intervention.

As such, the proposed project will be comprised of four stages:

Stage 1 – Description of Existing Community Hygiene Behaviors

In order to provide an in-depth and complete understanding of existing hygiene practices, the project will begin with formative qualitative and quantitative research techniques in order to interpret and augment the findings from the earlier stages of the project.

A Knowledge, Attitudes, and Practices (KAP) questionnaire will be used to interview the female heads of approximately fifty households randomly selected from similar but geographically separate communities of Las Pampas de San Juan de Miraflores to determine existing community-wide knowledge of and beliefs regarding hygiene behaviors. The results from the questionnaire will be evaluated in comparison with the results from earlier observations to examine how knowledge and beliefs correspond to actual behaviors.

Focus Group Discussions (FGD) with eight community volunteers from Manuel Scorza in separate groups of men, women, children, and adolescents will provide the first opportunities to share the findings from the earlier observational studies and the KAP surveys with community residents and receive their feedback, which will help with the identification of risk behaviors and which behaviors would be suitable for an intervention.

Purposive sampling, based on the findings of the earlier observations, will be used to select respondents for in-depth interviews. Interviews will be held with five community members from households shown to possess better than average hygiene behaviors and five community members from households that displayed worse hygiene behaviors. These interviews will employ a consultative research approach; first, gathering information on what factors: personal, social, and environmental, motivate or hinder handwashing, and then identifying ways that hygiene practices can be improved and this change sustained.

Stage 2 – Development of Hygiene Intervention

The development of the hygiene intervention will begin with the formation of a community-based hygiene working group, composed of volunteers recruited from the FGD. This group of volunteers will already be comprised of residents who view hygiene behavior as a significant problem in the community and who agree that the situation can and should be improved. Therefore, the principal dialogue will involve developing the means with which hygiene practices can be improved. Group activities, such as “planning posters” and “problem boxes,” will be employed to further discussions regarding the form of a locally-acceptable intervention message and the most effective channels for its distribution within the community.

Stage 3 – Implementation of Hygiene Intervention

As described above, the exact form of the hygiene intervention will be determined during the course of the project by the community-based hygiene working group. As such, the intervention will begin with a participatory approach and will later assume parts from other models, such as health education and social marketing.

Stage 4 – Evaluation of Hygiene Intervention

Continuous monitoring structured observations of the personal hygiene behaviors of residents will be used to determine the impact of the hygiene intervention. Post-intervention results will be compared with those of the baseline observations to determine the changes in behavior due to the intervention. Additionally, the KAP questionnaire will also be repeated to measure the changes in hygiene knowledge in a similar manner.

Evaluation will be based on various measures of 3 outcomes: risk awareness, improved hygiene behaviors, and improved community cohesion. It is expected that the community-based hygiene working group that will be formed to develop and implement the education program will continue to function during and following the conclusion of the project, representing a minimum level of increased community cohesion.

Significance

Water and sanitation projects and hygiene education aimed at behavior change are two important and widely-implemented health interventions. This project is aimed to further knowledge about how to best combine these two interventions to achieve maximum health-related behavior change and outcomes.

Methodologically, continuous monitoring is rarely used for intervention evaluations or measuring behavior change due to the complexity and expense involved, but this form of structured observation has the benefit of providing information on people’s actual behaviors as opposed to reported behaviors. As such, this proposal presents a unique opportunity to examine exactly the extent to which behaviors can be improved with a collaborative health education and promotion intervention. Additionally, community-based participatory research is currently receiving unprecedented attention, but much remains unknown about this methodology of attaining sustainability, so this project will add to this body of knowledge.

The study staff for the research project will also include a local nurse, who will be trained in participatory methods and qualitative research techniques in order to carry-out in-depth interviews, facilitate focus group discussions, and community meetings. Four other nurses will be recruited to help with the structured observations. In this way, local capacity building is built into the project.

A large part of the significance of this project lies in the potential benefits to the community. A collaborative approach will be employed where the findings from the earlier stages will be shared with community residents. This is intended to raise awareness about hygiene behaviors in the community. A hygiene working group will be formed, and together with the investigators, this group will use existing data and any additional data they wish to collect to develop the education and promotion intervention. Designed in this participatory and collaborative manner, the educational messages are more likely to be sustainable and locally acceptable. Furthermore, community participation in the development of the intervention may impart upon participants some critical skills, such as leadership, problem-solving, conflict resolution, and potentially the independence and initiative to formulate subsequent interventions and community-development projects. The community will benefit not only from improved hygiene and subsequent health outcomes but from the strengthening of community ties. Due to the nature of social development in Peru, a community’s organization and ability to advocate with local government is critical for the achievement of local development, in the form of infrastructure and service provision. If successful, this approach may be used in other disenfranchised peri-urban communities in Lima to promote community capacity building for sustainable positive change.

The proposed dissemination of findings is also key to this project’s significance. Final results and education messages will be shared with a national handwashing and hygiene behavior campaign in Peru, to help inform their tailoring of messages for peri-urban shantytown communities of Lima. Additionally, infrastructure installations are on the rise in these areas of Lima, and improved understanding of water usage and hygiene practices in such a peri-urban community may be useful for infrastructure projects in other shanty-towns, into which a similar hygiene education intervention could be included. As such, findings related to changes before and after the hygiene intervention and before and after the installation of at-home will also be presented to Lima’s drinking water administration.

On a final note, there is much personal significance to this project. Community-based participatory research and action is my primary interest in public health, and hygiene behaviors are a close second. I have been searching for an opportunity to gain practical experience in both.

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Sang Kim, PhD candidate in Epidemiology - "Center Effect" in Kidney Transplantation: A New Look at an Old Problem"

Title of Proposal: The “center effect” in kidney transplantation: A new look at an old problem
Introduction:
End-stage renal disease (ESRD) is a growing public health problem and is associated with a mortality
rate of ~20% per year, despite advances in dialysis therapy (1;2). Kidney transplantation is the preferred
treatment for ESRD patients since it enhances quality of life, improves long-term survival, and is more
cost-effective than dialysis (3-5). Although various clinical and immunologic predictors of transplant
success have been elucidated over the last several years, there is still uncertainty about the impact of
provider (including the transplant center or hospital) characteristics on kidney transplant outcomes (6-20).
Study Goals:
The study hypothesis is that there are identifiable(and potentially modifiable) provider characteristics,
at the level of clinicians and transplant centers, that may predict the outcome of kidney transplant
recipients and explain, at least in part, the variation in patient and kidney allograft survival across kidney
transplant centers in the United States.
To test the above hypothesis, this study will explore the relation between provider factors and shortand
long-term patient and allograft survival (at 1-, 3-, and 5-years post-transplant) in U.S. adult (age ≥ 18
years) kidney transplant recipients via the following two aims: (i) longitudinally assess the impact of
transplant center (e.g., average annual procedural volume, geographic locale, hospital size) and
physician/surgeon characteristics (e.g., clinical volume, years of practice, board certification status) on the
patient and allograft survival of 106,362 KTR (transplanted from January 1, 1994 to December 31, 2002
followed until December 31, 2003 by the United States Renal Data System) using a multi-level modeling
approach; the effect of provider factors on outcome will also be studied by year of transplantation and in
high-risk patient subgroups (e.g., second transplants); (ii) conduct a national survey of medical and
surgical directors of all 282 adult kidney transplant centers throughout the United States; information on
clinical protocols (e.g., use of induction therapy), follow-up care, and other practice patterns will be
ascertained; items that measure the degree and efficacy of teamwork between medical and surgical staff
will also be included.
Methods:
Study objective 1 will use information from the United States Renal Data System (USRDS) on all
kidney transplants performed in the United States from January 1, 1994 to December 31, 2002, along
with the American Hospital Association (AHA) and American Medical Association (AMA) databases, to
evaluate the role of transplant center and clinician (i.e., physician/surgeon) characteristics in influencing
patient and allograft survival in a cohort of KTR. Center characteristics of interest will include average
annual procedural volume, the number of years in existence as a kidney transplant program, total number
of hospital beds, profit status, number of transplant programs within the same city, presence of an
accredited transplant (nephrology/surgery) fellowship program, multi-organ vs. kidney-only transplant
program, and geographic locale. Transplant clinician factors will include physician and surgeon volumes
(number of KTR cared for per year), years of physician and surgeon experience (years of practice), board
certification status, and physician/surgeon specialty. Transplant physicians (i.e., clinicians trained in
general internal medicine and/or nephrology) are distinguished from transplant surgeons (i.e., clinicians
trained in general surgery, transplant surgery or urology) since the role of each group tends to differ in the
short- and long-term management of KTR at most U.S. centers. A secondary aim will be to determine the
effect of provider characteristics on the patient and allograft survival of high-risk subgroups (such as
second transplants and recipients of expanded criteria donor kidneys) and the role of transplant era
(defined by time points at which novel immunosuppressive agents were introduced into clinical practice)
in potentially altering the relation between transplant center/clinician-level factors and outcome.
Study objective 2 will involve a national survey of medical and surgical directors from all 282 adult
kidney transplant centers for the purpose of acquiring more detailed information on transplant center and
clinician characteristics (e.g., clinical practice patterns, measures of the degree and efficacy of teamwork
among medical and surgical transplant clinicians). An existing survey instrument will be revised and
extended in order to carry out this task (21). Measures of reliability and validity will be assessed during
Delta Omega Scholarship 2006 S. Joseph Kim, MD
March 20, 2006 Page 2
the piloting phase of survey development. Three periodic survey mailings, along with telephone, e-mail,
and/or fax reminders, will be used to maximize response rates. Endorsement of the survey by the
American Society of Transplantation and the American Society of Transplant Surgeons will be sought.
The results of the survey will provide a cross-sectional look at current practice patterns and the
organizational characteristics of U.S. adult kidney transplant centers. Moreover, it will provide a measure
of the teamwork that exists among medical and surgical transplant clinicians and how this teamwork is
manifested in the management of KTR. Future research will prospectively link these data to short- and
long-term outcomes of KTR to evaluate the relation between center-level practice patterns, organizational
characteristics, and measures of teamwork with patient and allograft survival.
Statistical Analyses:

For study objective 1, exploratory data analyses with descriptive statistics will be undertaken to
examine the distribution of exposure, confounder, and outcome variables. Potential confounders will be
examined within quartiles of total and average annual transplant center and clinician volume. Univariable
statistical relations will be tested using appropriate parametric and non-parametric tests for continuous
and categorical data. The Kaplan-Meier product limit method will be used to graphically examine the
relation between center/provider volume quartiles and both allograft and patient survival. The Cox
proportional hazards model will be used to examine the independent effect of covariates on time-to-event
outcomes (i.e., allograft failure and death). Two statistical approaches for the analysis of clustered data
will be pursued and the results compared: (i) marginal models using generalized estimating equations
(GEE) to account for the correlation of patient and allograft outcomes within transplant centers and
physicians/surgeons; (ii) random effects or multilevel models. Generally, marginal models will provide
hazard ratios with appropriate standard errors but, unlike random effects models, they can only address
questions regarding population average responses (i.e., no statements about center-specific effects can
be made) and do not permit the examination of variance components within and between clusters (22).
The random effects or multi-level Cox model provides a method to account for the nested data structure,
examine the variance components at each level of the data (i.e., center, clinician, and patient), and help
to stabilize estimates from centers with smaller volumes (via a procedure that uses the posterior
distribution of the overall effect estimate and the standard errors for each center) (23;24). With an
anticipated sample size of approximately 106,000 patients distributed over ~ 280 centers and a type 1
error rate of 0.05, this study will have 90% power to detect a hazard ratio of 1.15 for the outcome of graft
survival when comparing the lowest center volume quartile to the highest quartile (25).
For study objective 2, descriptive analyses will be performed using histograms, box plots, and lowess
smoothing techniques along with standard parametric and non-parametric methods for comparing
continuous and categorical data. Bivariate analyses will compare characteristics of kidney transplant
programs across center volume categories (e.g., tertiles or quartiles) and the presence of a linear
relationship in the responses of surgical and medical directors will be measured using Pearson’s
correlation coefficient. Assuming that a response rate of 54% is achieved (26), 282 x 0.54 = 152 centers
will return completed questionnaires. Given that differences between responders and non-responders
with respect to key factors such as the geographic location of transplant programs are not significant, a
sample size that constitutes > 50% of all centers should provide sufficient data to adequately describe the
variation in the characteristics of interest across U.S. kidney transplant centers.
Significance:
The anticipated results of this study will further the scientific debate regarding the factors that
contribute to the center effect in kidney transplantation. The study will identify potentially modifiable
characteristics of transplant centers and/or clinicians that may help to mitigate existing variations in
center-specific outcomes. This information may also be used develop and implement interventions to
improve the performance of transplant centers and enhance the quality of care provided to kidney
transplant recipients. Finally, the results of this study will inform the efforts of policy makers in weighing
the pros and cons of regionalizing complex and expensive health services such as kidney transplantation.
Delta Omega Scholarship 2006 S. Joseph Kim, MD
March 20, 2006 Page 3
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Rachel Singer, PhD candidate in Health Policy and Management - Mobilizing the Masses: Potential for Universal Coverage in Maryland

Mobilizing the Masses: The Potential for Universal Coverage in Maryland

According to a March 2006 Gallup Poll, 68 percent of Americans worry “a great deal” about “the availability and affordability of healthcare.” At the beginning of the twenty-first century, the United States is the only industrialized nation that does not provide health care for all its citizens. While proposals for universal health insurance have routinely come before Congress since the First World War, they failed to pass time and time again. Over the last century, efforts towards universal coverage resulted in incremental, rather than monumental, reforms, providing coverage only for individual segments of the population. In 2004, 46 million Americans did not have health insurance (U.S. Census Bureau 2005). According to a recent report by the Institute of Medicine (2004), uninsured children and adults do not receive timely care, and die earlier than those with insurance. Insurance matters not just to the health of the individual, but to the very survival of community and society. The lack of a unified grassroots effort to combat this injustice has enabled pharmaceutical and insurance companies, and their supporters to get away with murder.

Scholars frequently cite the lack of a unified, grassroots movement to counter the well-organized and well-financed stakeholders in opposition to universal coverage as the reason why past health reform efforts have failed. Analyses of past failures have concluded that an organized grassroots movement will be necessary for the success of future reform (Derickson 2005; Gordon 2003; Mayes 2003; Quadagno 2005). As employment-based insurance continues to de-stabilize in tandem with changes in the economy and increasing healthcare costs, the number of individuals without insurance has increased dramatically and the need to address the problem has become more critical. While the public has expressed the desire for changes in the system, change is not possible without grassroots efforts on the part of citizens, locally and nationally. Since the late 1980s, various state movements emerged to advocate for universal healthcare. In Maryland, the “Maryland Healthcare For All!” initiative was established in 2000 with the goal of “create(ing) a comprehensive, economically sound health care” plan for every citizen. In order for this movement to be successful, its direct connection with as many citizens in the state of Maryland is integral.

Beatrix Hoffman (2003) critiques certain statewide health reform movements for “emphasizing coalitions of professional advocacy groups as the centerpiece of their organizing strategies.” Hoffman explains that reform leaders often fail to accomplish their goals because of reform leaders’ “lack of knowledge, lack of interest in, or outright exclusion of popular reform constituencies and grassroots organizing strategies.”

Efforts to achieve national health insurance throughout the twentieth century were generally products of elite policymakers, social scientists, public health professionals, and labor leaders. My goal is to determine whether the Maryland Citizens’ Health Initiative is a true “grassroots” movement, or if it is an organization designed by well-intentioned non-grassroots advocates. If the latter is indeed the case, it is critical that the initiative make it a priority to connect directly with citizens, not merely other interest groups whose individual goals will stand in the way of universal healthcare for all. In its communication with interest groups, the initiative must also make it a priority to speak to those groups in the language of their own movements.

Using the case study method, I plan to analyze the movement from its inception, to trace the lines of communication between the movement’s leadership and the citizens, and to determine the movement’s potential success or potential failure in context of other grassroots movements and their results throughout twentieth century American history. The case study method is best suited to answering “how” and “why” questions, and for understanding phenomenon and their context (Yin 2003). I selected the Maryland “Health Care for All” coalition as my single case study. Sources of evidence for this study, as described by Yin, include documents (e.g. organizational materials, news articles, newsletters), in-depth interviews, and participant observation.

Some social movement researchers argue that social movements have become so professionalized since the early 1970s to render them useless. Has corporate capitalism so overwhelmed the policy-making process that ordinary citizens are no longer vital contributors to decision-making? Or, does the potential exist for an unprecedented grassroots movement to combat runaway abuse of American democratic principles by all-powerful drug and insurance companies?

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