Assessment of US Air Force student pilots with intermittent monofixation syndrome on a non-stereoptic dependent flight maneuver in pilot training

The United States Air Force School of Aerospace Medicine (USAFSAM) and Aeromedical Consult Service (ACS) have developed waiver criteria for pilots with subtle substandard depth perception. This is to allow United States Air Force (USAF) pilots with mild depth perception deficiency to continue flying duties while limiting the risk to flight safety and ensuring the availability of costly human resources. From 1999 to 2005, 166 aviators were given waivers for intermittent monofixation syndrome (IMFS). Of these, 96 were student pilots who performed slightly worse at stereoptic dependent flight maneuvers than student pilots (8,907) with normal depth perception (Lowry, 2006).^ This study's purpose is to evaluate the performance of the extended-trail maneuver, a non-stereoptic dependent flying maneuver, as executed by a cohort of 12 United States Air Force student pilots with intermittent monofixation syndrome versus the cohort of 100 student pilots with normal depth perception. These subjects are extracted from the cohorts examined by Lowry (2006) and the null hypothesis predicts no statistical difference in the performance of the non-stereoptic dependant flight maneuver extended-trail between student pilots with intermittent monofixation syndrome and those without the condition. ^

Antiretroviral therapy adherence and the use of condoms among African American HIV-positive crack cocaine users

Safer sex practices, such as consistent condom use, are essential to reduce HIV transmission. Determining causes and/or co-variants related to the likelihood of participating in high-risk sexual behaviors may allow the content of interventions and treatments to minimize HIV transmission to be tailored more effectively. The goal of this study was to examine whether a relationship exists between consistent condom use among African American HIV-positive crack cocaine users and both (1) the use of antiretroviral therapy, and (2) adherence to antiretroviral therapy regimens. The study population consisted of 390 participants. They were at least 18 years old, African American, HIV-positive, and had used crack cocaine within a month prior to an interview conducted sometime between April, 2004, and September, 2007. Bivariate associations were examined using contingency tables and χ2-statistics. The Mantel-Haenszel method was used to control for confounding. This study found neither a significant relationship between use of antiretroviral therapy and consistent condom use (Odds ratio (OR) = 1.38; 95% Confidence interval (95%CI) = 0.86–2.22), nor an association between antiretroviral therapy adherence and consistent condom use (OR = 1.02, 95%CI = 0.60–1.75). The exception was more consistent condom use when sex was traded for money or drugs in those on antiretroviral therapy, compared to those not on such therapy (OR = 2.28, 95%CI = 1.08–4.85). Further studies examining condom use and HIV treatment adherence are recommended. ^

Demographics of having a gun in the home in Columbia, SC as reported by women primary care patients

Objectives. To determine demographic correlates of having one or more guns in the household of women primary care patients in the southern USA. ^ Methods. All participants in this cross-sectional study were women aged 18-65 who were insured by either Medicaid or a managed care provider and had ever had an intimate sexual relationship with a male partner that lasted at least three months. Prevalence rate ratios and 95% confidence intervals were calculated using stratified analyses for having a gun in the home and the following demographic factors: age, race, educational attainment, marital status, employment status, and alcohol/drug use. ^ Results. Twenty six percent of households had at least one gun and 6.5% had 3 or more guns. The following demographic characteristics of women were associated with having a gun in the household: age (>40) (prevalence rate ratio [PRR] = 1.4; 95% confidence interval [CI] = 1.1–1.8); White race (PRR = 1.89; 95% CI = 1.61–2.27); currently being employed (PRR = 1.72; 95% CI = 1.22–2.44); higher education; and being insured by an HMO (PRR = 1.92; 95% CI = 1.47–2.50). Neither the partner's unemployment nor his substance use was associated with having a gun. While White households were more likely to have a gun, the same correlates of gun ownership held for both White and African-American households; being married or living as married and higher socio-economic status (i.e. HMO insurance and being employed) were strongly correlated with gun in the household. The following were correlated with having multiple guns in the household: White race (p < 0.0001); increased age (p = 0.005); being currently married or living as married (p < 0.0001); and HMO insured status (p < 0.0001). Among those households with at least one gun, White race and married or currently living as married were associated with having 2 or more guns relative to one gun in the household. ^ Conclusions. Currently living with a man and being of higher socio-economic status were strong correlates of household gun ownership among both Whites and African-Americans. Substance use was not associated with household gun ownership. ^

Racial disparities in patient survival after liver transplantation in the United States

Background. Racial disparities in healthcare span such areas as access, outcomes after procedures, and patient satisfaction. Previous work suggested that minorities experience less healthcare and worse survival rates. In adult orthotopic liver transplantation (OLT) mixed results have been reported, with some showing African-American recipients having poor survival compared to Caucasians, and others finding no such discrepancy. ^ Purpose. This study’s purpose was to analyze the most recent United Network for Organ Sharing (UNOS) data, both before and after the implementation of the Model for End-Stage Liver Disease (MELD)/Pediatric End-Stage Liver Disease (PELD) scoring system, to determine if minority racial groups still experience poor outcomes after OLT. ^ Methods. The UNOS dataset for 1992-2001 (Era I) and 2002-2007 (Era II) was used. Patient survival rates for each Era and for adult and pediatric recipients were analyzed with adjustment. A separate multivariate analysis was performed on African-American adult patients in Era II in order to identify unique predictors for poor patient survival. ^ Results. The overall study included 66,118 OLT recipients. The majority were Caucasian (78%), followed by Hispanics (13%) and African-Americans (9%). Hispanic and African-American adults were more likely to be female, have Hepatitis C, to be in the intensive care unit (ICU) or ventilated at time of OLT, to have a MELD score ≥23, to have a lower education level, and to have public insurance when compared to Caucasian adults (all p-values < 0.05). Hispanic and African-American pediatric recipients were more likely have public insurance and less likely to receive a living donor OLT than were Caucasian pediatric OLT recipients (p <0.05). There was no difference in the likelihood of having a PELD score ≥21 among racial groups (p >0.40). African-American adults in Era I and Era II had worse patient survival rates than both Caucasians and Hispanic (pair-wise p-values <0.05). This same disparity was seen for pediatric recipients in Era I, but not in Era II. Multivariate analysis of African-American recipients revealed no unique predictors of patient death. ^ Conclusions. African-American race is still a predictor of poor outcome after adult OLT, even after adjustment for multiple clinical, demographic, and liver disease severity variables. Although African-American and Hispanic subgroups share many characteristics previously thought to increase risk of post-OLT death, only African-American patients have poor survival rates when compared to Caucasians. ^

Determining appropriate measurement methods for etiological research of computing-related musculoskeletal symptoms and disorders

Two studies among college students were conducted to evaluate appropriate measurement methods for etiological research on computing-related upper extremity musculoskeletal disorders (UEMSDs). ^ A cross-sectional study among 100 graduate students evaluated the utility of symptoms surveys (a VAS scale and 5-point Likert scale) compared with two UEMSD clinical classification systems (Gerr and Moore protocols). The two symptom measures were highly concordant (Lin's rho = 0.54; Spearman's r = 0.72); the two clinical protocols were moderately concordant (Cohen's kappa = 0.50). Sensitivity and specificity, endorsed by Youden's J statistic, did not reveal much agreement between the symptoms surveys and clinical examinations. It cannot be concluded self-report symptoms surveys can be used as surrogate for clinical examinations. ^ A pilot repeated measures study conducted among 30 undergraduate students evaluated computing exposure measurement methods. Key findings are: temporal variations in symptoms, the odds of experiencing symptoms increased with every hour of computer use (adjOR = 1.1, p < .10) and every stretch break taken (adjOR = 1.3, p < .10). When measuring posture using the Computer Use Checklist, a positive association with symptoms was observed (adjOR = 1.3, p < 0.10), while measuring posture using a modified Rapid Upper Limb Assessment produced unexpected and inconsistent associations. The findings were inconclusive in identifying an appropriate posture assessment or superior conceptualization of computer use exposure. ^ A cross-sectional study of 166 graduate students evaluated the comparability of graduate students to College Computing & Health surveys administered to undergraduate students. Fifty-five percent reported computing-related pain and functional limitations. Years of computer use in graduate school and number of years in school where weekly computer use was ≥ 10 hours were associated with pain within an hour of computing in logistic regression analyses. The findings are consistent with current literature on both undergraduate and graduate students. ^

Tobacco use and related psychosocial risk factors among youth in urban India: Assessment of Project MYTRI follow-up surveys

Project MYTRI (Mobilizing Youth for Tobacco-Related Initiatives in India) was a large 2-year randomized school-based trial with a goal to reduce and prevent tobacco use among students in 6th and 8th grades in Delhi and Chennai in India (n=32 schools). Baseline analyses in 2004 showed that 6th grade students reported more tobacco use than 8 th grade students, opposite of what is typically observed in developed countries like the US. The present study aims to study differences in tobacco use and psychosocial risk factors between the 6th grade cohort and 8th grade cohort, in a compliant sub-sample of control students that were present at all 3 surveys from 2004-06. Both in 2004 and 2005, 6th grade cohort reported significantly greater prevalence of ever use of all tobacco products (cigarettes, bidis, chewing tobacco, any tobacco). These significant differences in ever use of any tobacco between cohorts were maintained by gender, city and socioeconomic status. The 6th grade cohort also reported significantly greater prevalence of current use of tobacco products (cigarettes, chewing tobacco, any tobacco) in 2004. Similar findings were observed for psychosocial risk factors for tobacco use, where the 6th grade cohort scored higher risk than 8th grade cohort on scales for intentions to smoke or chew tobacco and susceptibility to smoke or chew tobacco in 2004 and 2005, and for knowledge of health effects of tobacco in all three years.^ The evidence of early initiation of tobacco use in our 6th grade cohort in India indicates the need to target prevention programs and other tobacco control measures from a younger age in this setting. With increasing proportions of total deaths and lost DALYs in India being attributable to chronic diseases, addressing tobacco use among younger cohorts is even more critical. Increase in tobacco use among youth is a cause for concern with respect to future burden of chronic disease and tobacco-related mortality in many developing countries. Similarly, epidemiological studies that aim to predict future death and disease burden due to tobacco should address the early age at initiation and increasing prevalence rates among younger populations. ^

Malaria prevention in Kenyan women of childbearing age

The objective of this program is to reduce malaria incidence in Kenya. Malaria poses a large public health challenge in Kenya, and although public health efforts have traditionally been focused on treatment of infected patients, due to increased drug resistance and lack of drug-adherence, prevention strategies are needed. This program targets Kenyan women, the likely caretakers in the home, and promotes malaria prevention behaviors through health education. ^ A planning group will be assembled and a needs assessment will be performed, verifying risk factors and conditions associated with malaria, as well as personal and external determinants. Behavioral and environmental outcomes will be determined, and performance objectives for each outcome will be established. Matrices of change objectives will be created, and detailed methods and strategies will be linked to each change objective. Program elements include media, education, and incentives. All materials used in this program will be subjected to pre-test to ensure cultural relevance and fidelity. Matrices of change objectives will be created for program adopters and implementers, as well as correlating methods and strategies associated with each change objective. Performance objectives will also be compiled for program maintainers. A program evaluation plan will follow "Pre-Post Comparison Group" design. Outcome evaluation and process evaluation will be conducted. The sample population will be screened based on age and gender so as to maintain comparability to the target population. Measurements will be taken before the program to establish baseline, directly following the program to determine short-term effects, and three months after the program is completed to determine long-term effects. ^ One limitation of this program is selection bias, due to the nature of quasi-experimental studies. Thorough screening prior to sample selection will minimize selection bias and ensure group homogeneity. Another limitation is attrition, and this will be minimized where possible through the use of incentives. In cases where loss to follow-up is not avoidable, such as death or natural disasters, the attrition effect will be estimated using structural equation modeling after reviewing the sample size, differential attrition and total attrition. ^ This intervention is based heavily on health promotion theories, but it is important to remember that in the field, the program plan will likely include only the necessary practical strategies. The target population, Kenyan women of childbearing age, will be significant in decreasing the malaria disease burden in Kenya.^

Long-term gastrointestinal complications of Clostridium difficile associated diarrhea (CDAD)

Background. The incidence of Clostridium difficile -associated diarrhea (CDAD) is increasing worldwide likely because of increased use of broad spectrum antibiotics and the introduction of a clonal hyper-virulent strain called the BI strain. Short-term complications of CDAD include recurrent disease, requirement for colectomy, and persistent disease. However, data on the long-term consequences of CDAD are scarce. Among other infectious diseases (Shigella, Salmonella, and Campylobacter), long-term consequences such as irritable bowel syndrome (IBS), chronic dyspepsia/diarrhea, and other GI effects have been noted. Since the mechanism of action of these agents is similar to C.difficile, we hypothesized that patients with CDAD have greater likelihood of developing IBS and other functional gastrointestinal disorders (FGIDs) in the long-term as compared to a general sample of recently hospitalized patients. ^ Objective. To evaluate the long-term gastrointestinal complications of CDAD, (IBS, functional diarrhea, functional abdominal bloating, functional constipation and functional abdominal pain syndrome). ^ Methods. The current study was a secondary analysis of a previously completed observational case-control outcome study. Adult CDAD patients at St. Luke's Episcopal Hospital, Houston (SLEH) were followed up and interviewed by telephone six months after the initial diagnosis thereafter evaluated for the development of IBS and other FGIDs. A total of 46 patients with CDAD infection were recruited at SLEH between May-November 2007. The comparators were patients hospitalized in SLEH within one month before or after the admission of the reference case, hospital length of stay within one week longer or shorter than reference case, and age within 10 years more or less than the reference case. Cases and comparators were compared using Fisher's exact test. A p<0.05 was considered significant. ^ Results. Thirty CDAD patients responded to the questionnaires and were compared to 40 comparators. No comparator developed a FGID, while 3 (10%) CDAD patients developed new onset IBS (p=0.07), 4 (13.3%) developed new onset Functional Diarrhea (p=0.03), and 3 (10%) developed new onset Functional Constipation (p=0.07). No patient developed Functional Abdominal Bloating and Functional Abdominal Pain Syndrome. ^ Conclusion. In this study, new onset functional diarrhea was significantly more common in patients CDAD within six months after initial infection compared to matched controls.^

Federal regulation of human embryonic stem cell research

President George W. Bush's 2001 statement, which laid out guidelines for research that uses human embryonic stem cells to qualify for federal funding, intends to prevent new embryonic stem cell lines from being developed, by prohibiting the federal funding of research that uses embryonic stem cell lines other than those that existed at the time of the policy's inception and were approved by the National Institutes of Health. This policy raises questions of medical and technological ethics and the governments' role in making decisions regarding the advancement of science based on moral and political opinions. Federal stem cell usage policy directly affects scientific research efforts that are currently on the path to understanding the mechanisms of cell differentiation and could potentially offer answers and therapies for disabilities and many chronic diseases. By reviewing the current literature on the background information on human embryonic stem cells, including what they are, where they come from, how they are used for research purposes, and the ethical controversy surrounding their use, I have researched and reported the impact of the 2001 policy on medical research. ^ Both those who support the current policy on human embryonic stem cell research and those who are advocates for policy change have relevant arguments and varying opinions on human embryonic stem cell usage itself. The ethical implication of how embryonic stem cells are obtained has led to fierce debate. This paper presents many arguments for and against hESC research in addition to the policy governing their use. This analysis concludes that the current policy on federal funding of human embryonic stem cell research should be revised to allow research using new stem lines to be eligible for federal funding under specific guidelines. Supporting evidence for this recommendation is provided.^

Diffusely adherent Escherichia coli (DAEC) as a cause of acute diarrhea

Acute diarrhea is the most common medical problem in the developing countries. Infectious agents are responsible for a majority of cases of acute diarrhea. Knowing the cause of acute diarrhea is important to developing plans for disease prevention, control and therapy. Acute diarrhea is caused by many viruses, bacteria and parasites. ^ Travelers to developing countries of the world commonly develop diarrhea as a result of eating contaminated food or drinking contaminated water. About 30-50% of travelers who travel from industrialized countries like United States to the developing countries are at risk of developing diarrhea. High risk areas for travelers' diarrhea are Mexico, Latin America and Southeast Asia. Public restaurants are the common sites for exposure to this type of food-borne infectious disease in travelers. Food becomes contaminated when they are handled by people with fecal content on their hands. ^ The importance of Diffusely Adherent Escherichia Coli (DAEC) in travelers to these areas has not been well studied. Some of the studies looking at DAEC have shown the organism to be present in children without symptoms. Other studies have shown a relationship between DAEC infection and presence of symptoms. I have selected this topic because the patho-physiological processes in DAEC infection that allow intestinal and extra-intestinal infections to develop are not fully understood. DAEC related acute diarrhea is a relatively new topic of public health significance. There is a limited number of studies regarding the virulence and pathogenic mechanisms of DAEC. The presumed virulence factor of the organism is diffuse attachment to the intestinal lining of the infected host. However more research needs to be done to identify the pathogenic mechanisms and virulence factors associated with DAEC infection for better treatment planning and diarrhea prevention. ^

Gastric cancer survival amongst Hispanics- A Hispanic paradox? A case series study using the SEER 1973--2005 data registry

Stomach cancer is the fourth most common cancer in the world, and ranked 16th in the US in 2008. The age-adjusted rates among Hispanics were 2.8 times that of non-Hispanic Whites in 1998-2002. In spite of that, previous research has found that Hispanics with non-cardia adenocarcinoma of the stomach have a slightly better survival than non-Hispanic Whites. However, such previous research did not include a comparison with African-Americans, and it was limited to data released for the years 1973-2000 in the nine original Surveillance, Epidemiology, and End Results Cancer Registries. This finding was interpreted as related to the Hispanic Paradox, a phenomenon that refers to the fact that Hispanics in the USA tend to paradoxically have substantially better health than other ethnic groups in spite of what their aggregate socio-economic indicators would predict. We extended such research to the SEER 17 Registry, 1973-2005, with varying years of diagnosis per registry, and compared the survival of non-cardia adenocarcinoma of the stomach according to ethnicity (Hispanics, non-Hispanic Whites and African-Americans), while controlling for age, gender, marital status, stage of disease and treatment using Cox regression survival analysis. We found that Hispanic ethnicity by itself did not confer an advantage on survival from non-cardia adenocarcinoma of the stomach, but that being born abroad was independently associated with the apparent 'Hispanic Paradox' previously reported, and that such advantage was seen among foreign born persons across all race/ethnic groups.^

Are free condoms associated with the frequent use of condoms among men who have sex with men?

Introduction. The National Behavioral HIV Surveillance (NHBS) is a self-reported cross-sectional survey that monitors the spread of human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS). The 2004 survey asked if the participant received a free condom, used it, and if receiving a free condom made him more likely to use a condom. The aim of this cross-sectional study is to examine the Houston MSA sub-dataset to determine if there was a self-expressed association between receiving a free condom and likelihood of using a condom at next intercourse, and to determine if the strength of that association varied by demographic subgroup.^ Methods. The Houston MSA 2004 NHBS had 502 participants who were men who have sex with men (MSM). The present analysis examined the answers to the questions: "In the past 12 months, have you received free condoms?" "Have you used any of the free condoms you received?" and "Did getting these free condoms make you more likely to use condoms during sex?".^ Results. Out of 502 participants, 500 answered the question about receiving free condoms, 406 (81.2%) answered all three questions, and 204 (50.2%) answered "yes" to all three questions. In the subgroup analyses, Hispanics were significantly less likely and men under 29 years of age were significantly more likely to report that their condom use behavior was influenced by receiving a free condom. ^ Conclusion. The effect of receipt of free condoms on likelihood of condom use varies by demographic subgroup, but these potentially important preliminary findings will require further investigation to validate them and further explicate the possible underlying dynamics.^

Evaluating minimal important differences for the FACT-Melanoma quality of life questionnaire

Objectives. Minimal Important Differences (MIDs) establish benchmarks for interpreting mean differences in clinical trials involving quality of life outcomes and inform discussions of clinically meaningful change in patient status. As such, the purpose of this study was to assess MIDs for the Functional Assessment of Cancer Therapy–Melanoma (FACT-M). ^ Methods. A prospective validation study of the FACT-M was performed with 273 patients with stage I to IV melanoma. FACT-M, Karnofsky Performance Status (KPS), and Eastern Cooperative Oncology Group Performance Status (ECOG-PS) scores were obtained at baseline and 3 months following enrollment. Anchor- and distribution-based methods were used to assess MIDs, and the correspondence between MID ranges derived from each method was evaluated. ^ Results. This study indicates that an approximate range for MIDs of the FACT-M subscales is between 5 to 8 points for the Trial Outcome Index, 4 to 5 points for the Melanoma Combined Subscale, 2 to 4 points for the Melanoma Subscale, and 1 to 2 points for the Melanoma Surgery Subscale. Each method produced similar but not identical ranges of MIDs. ^ Conclusions. The properties of the anchor instrument employed to derive MIDs directly affect resulting MID ranges and point values. When MIDs are offered as supportive evidence of a clinically meaningful change, the anchor instrument used to derive thresholds should be clearly stated along with evidence supporting the choice of anchor instrument as the most appropriate for the domain of interest. In this analysis, the KPS was a more appropriate measure than the ECOG-PS for assessing MIDs. ^

Lessons learned from nationwide vaccine programs: Comparing human papillomavirus, poliomyelitis vaccine, and swine flu

This assessment compares the human papillomavirus (HPV) nationwide vaccine to the poliomyelitis vaccine and the swine flu vaccine with the purpose of finding parallels and lessons in the controversies faced by the development and use of the vaccines. There are a number of great barriers that are facing the HPV vaccine to date. These controversies lie in dealing with the risk involved in taking the vaccine, how much control the government should have in administering the vaccine, how to communicate the risk to the public, and the cost-effectiveness of the vaccine versus treatment for cervical cancer. The lessons for the HPV vaccine that were learned after comparison and assessment of the controversies were: (1) plan ahead of time on how to inform the public if a risk develops from taking the HPV vaccination and it may be better to provide some information while the event is occurring, always being as truthful as possible, and later dispensing more information once all of the facts are known, (2) the human papillomavirus is not something that will become a pandemic in a short amount of time because the virus takes a long time to develop into cervical cancer, so if a major risk begins to show after continuing to develop and administer the vaccine for an amount of time, it may be better to take it off the market for a while and possibly reconfigure it to help eliminate some of the risks, (3) if side reactions and risks do develop and the government assumes liability for these reactions, the cost-effectiveness can be greatly affected, so it is important to be constantly checking to see if all the monetary and health benefits of the vaccine are outweighing any of the negative costs of the vaccine, and lastly, (4) the public must feel that every aspect of the vaccine, both good and bad, has been thought over and the benefits of taking the vaccine prevail over the negatives and that politics and commercial interests have nothing to do with the production and administration of the vaccine. ^

Youth empowerment evaluation to improve afterschool programming

Community-based participatory research necessitates that community members act as partners in decision making and mutual learning and discovery. In the same light, for programs/issues involving youth, youth should be partners in knowledge sharing and evaluation (Checkoway & Richards-Schuster, 2004). This study is a youth-focused empowerment evaluation for the Successful Youth program. Successful Youth is a multi-component youth development after-school program for Latino middle school youth, created with the goal of reducing teen pregnancy. An empowerment evaluation is collaborative and participatory (Balcazar and Harper 2003). The three steps of an empowerment evaluation are: (1) defining mission, (2) taking stock, and (3) planning for the future (Fetterman 2001).^ In a program where youth are developing leadership skills, making choices, and learning how to self reflect and evaluate, the empowerment evaluation could not be more aligned with promoting and enhancing these skills. In addition, an empowerment evaluation is designed to "foster improvement and self-determination" and "build capacity" (Fetterman 2001). Four empowerment groups were conducted with approximately 6-9 Latino 7th grade students per group. All participants were enrolled in the Successful Youth program. Results indicate points where students' perceptions of the program were aligned with the program's mission and where gaps were identified. Students offered recommendations for program improvements. Additionally, students enjoyed expressing their feelings about the program and appreciated that their opinions were valued. Youth recommendations will be brought to program staff; and, where possible, gaps will be addressed. Empowerment evaluations with youth will continue during the duration of the program so that youth involvement and input remains integral in the evaluation and to ascertain whether the program's goals are being met. ^