Biomedical subjects

Robert F Woolson

Publications and source records attributed to Robert F Woolson.

31 records · Page 2Linked to original sources

PubMed2003

Viral induced fusion and syncytium formation: measurement by the Kolmogorov-Smirnov statistical test.

Fusion and syncytium formation induced by the expression of fusogenic viral glycoproteins are common cytopathic effects. Numerous laboratories have studied mechanisms of fusion, generally with each laboratory utilizing a different method to measure polykaryote formation. There is little consensus as to which methods are preferred for measuring and comparing fusion. The Kolmogorov-Smirnov two-sample test was used to document a statistical difference in syncytium formation between two forms of a varicella-zoster virus (VZV) fusogenic glycoprotein. This test is widely applied toward the analysis of large human populations in which interest centers on testing the hypothesis that the distributions of two sub-populations are identical. We suggest that the Kolmogorov-Smirnov test is a preferable method to assess whether differences in distribution of syncytia size between two fusogenic glycoproteins are meaningful statistically.

Cytopathogenic Effect, Viral↗

PubMed2002

Health-related quality of life in Gulf War era military personnel.

The Gulf War's impact on veterans' health-related quality of life (HRQL) remains unclear. The authors examined the HRQL of military personnel deployed to the Gulf War Theater compared with those not deployed. In 1995-1996, a structured, population-based telephone survey was conducted 5 years postconflict among a cohort originally from Iowa on active duty during the conflict. The sample included 4,886 eligible subjects stratified by deployment and military status and proportionately distributed within five substrata. The Medical Outcome Study Short Form-36 (SF-36) assessed HRQL, and multivariable linear regression identified pre- and perideployment risk factors. A total of 3,695 respondents (76%) participated. Nondeployed participants reported excellent health more often than deployed participants (31% vs. 21%, p < 0.01). SF-36 scores for deployed participants were poorer than those for nondeployed controls across all health domains. Modifiable factors such as smoking and military preparedness, and other factors such as predeployment physical and mental health morbidity, were independent risk factors for poorer HRQL after deployment. Deployed veterans reported slightly poorer HRQL even after the authors adjusted for other risk factors. Further investigation of factors influencing postdeployment HRQL is needed. Routine collection of health information by using standardized instruments pre- and perideployment should be implemented.

Adult↗

PubMed2002

Methodologic issues in a population-based health survey of Gulf War veterans.

This report describes the principal methods used in the development, conduct, and analysis of the research study "Health Assessment of Persian Gulf War Veterans from Iowa" (Iowa Gulf War Study). The methods presented include an outline of the organizational structure, study timeline, hypotheses, outcome definitions, and study design. Adhering to a strict timeline, the study protocol and instruments were developed, and a stratified sample of 3,695 military personnel (76% participation) was located and surveyed by structured telephone interview. The study tracked personnel from all service branches residing nationally and internationally, including those discharged from service. This study required development and implementation of methods appropriate to analysis of data collected in a complex sampling framework and methodological procedures to ensure scientific rigor in a highly public and politicized environment. Statistical analyses were conducted on a priori health outcomes and required development of methods to compute Cochran-Mantel-Haenszel adjusted rate differences. This environment facilitated rapid implementation, critique by scientific and public advisors, a high participation rate, and rapid publication.

Adult↗

PubMed2002

Physician knowledge, attitudes and practices regarding a widely implemented guideline.

RATIONALE, AIMS AND OBJECTIVES: Although clinical practice guidelines have been promoted widely, there is considerable concern that physicians have not incorporated them into their practice. Models suggest that a 'knowledge-attitude-behaviour' sequence is important in modifying physician practice patterns. To address this, we examined physicians' knowledge of, attitudes towards and compliance with a widely implemented guideline - the Agency for Health Care Policy and Research (AHCPR) smoking cessation guideline. METHODS: A survey was mailed to a random sample of physicians at 128 veterans health administration facilities, which had implemented the guideline 2 years previously. RESULTS: Completed surveys were received from 879 physicians (50.3 response rate). Only 26 of physicians reported receiving a copy or summary of the guideline, 44 reported little or no familiarity with it, 42 did not know if they agreed with it, 40 did not know if they complied with it and 46 did not know if it was effective. However, a high percentage of physicians reported that they always or usually explain the health risks of smoking (86) and that they always or usually suggest that their smoking patients stop (94). CONCLUSIONS: In spite of little familiarity with the guideline, the responding physicians reported practice patterns consistent with adherence to it. Knowledge is only one of a spectrum of barriers that affects physician adherence to guidelines. There are numerous opportunities for health care organizations to overcome the barriers to physician adoption of clinical practice guidelines in their day-to-day practice.

Adult↗

PubMed2002

Organizational and provider characteristics fostering smoking cessation practice guideline adherence: an empirical look.

We examined the relationship between physician adherence with a smoking cessation guideline and organizational structures, policies, leadership support, and physician knowledge and attitudes. A random sample of 844 physicians practicing in 127 VHA hospitals was surveyed. Survey results were aggregated to the hospital level and linked with data on organizational characteristics from the 1998 annual survey of hospitals by the American Hospital Association. Significant predictors of adherence included organizational policies related to nicotine replacement prescriptions, the timing and effectiveness of guideline implementation, physicians' knowledge of VHA clinical guidelines generally, and physicians' beliefs about the receptiveness of patients to smoking cessation.

American Hospital Association↗

PubMed2002

Benchmarking Veterans Affairs Medical Centers in the delivery of preventive health services: comparison of methods.

OBJECTIVE: To identify consistent provision of clinical preventive services, we sought to benchmark all acute care Veterans Affairs Medical Centers (VAMCs) against each other nationally on the basis of multiple evidence-based, performance measures to identify facilities performing consistently higher and lower than expected. METHODS: The 1998 Veterans Health Survey assessed the self-reported delivery of evidence-based clinical preventive services in a stratified national sample of 450 ambulatory care patients seen at each VAMC. Proportions appropriately receiving each service within the recommended time interval were calculated for 138 VAMCs. Percentile ranks for each outcome were assigned. Two approaches were used for benchmarking performance. First, a scaled score for each facility was calculated across the set of 12 measures. Second, facilities were ranked based on the sum of the percentile ranks over a range of specific high cutoffs (eg, 70-80%) and above a range of lower cutoffs (eg, 40-50%). Ranking was validated by comparing with deciles of ranks on chart audit (External Peer Review Program, EPRP) data using Kendall's tau-b and chi2 quality-of-fit test. Differences between consistently high adherence (CHA) and low adherence (CLA) facilities were compared using the Wilcoxon rank sum test on 14 VHS and 11 EPRP outcomes. RESULTS: Data from 39,939 patients (67% response rate) were examined. In combination, cutoffs of greater than 50th percentile and greater than 75th percentile rank yielded 12 of 14 VHS and 6 of 11 EPRP measures different between CHA and CLA facilities. The scaled-score approach resulted in 20 CHA and 14 CLA facilities. The sum of outcomes ranked above 50th percentile and over 75th percentile for CHA facilities (n = 17) was 15 or more. The sum of outcomes ranked above the same cutoffs for CLA facilities (n = 16) was 3 or less. EPRP and 1998 VHS data demonstrated that the survey measures and benchmarking approaches were both reliable and valid. Both approaches resulted in multiple differences between CHA and CLA facilities; differences were greater using the percentile rank approach. CONCLUSIONS: The VA has successfully encouraged adoption of evidence-based clinical preventive services throughout its health care system. However, facilities show wide variation in their levels of delivery and can be distinguished on the basis of their consistently high or low levels of adherence. Examining service delivery across multiple performance indicators allows identification of opportunities to improve clinical practice guideline implementation and the delivery of preventive services. This approach identifies model institutions where focused investigation of factors associated with consistent performance may be particularly fruitful.

Adult↗

PubMed2002

Organizational predictors of adherence to ambulatory care screening guidelines.

OBJECTIVE: The purpose of this study was to identify hospital organizational characteristics consistently associated with adherence to multiple clinical practice guidelines (CPGs). We examined the relationship between organizational and patient population characteristics and adherence to three screening CPGs implemented throughout the Veterans Health Administration (VHA). MATERIALS AND METHODS: The study included 114 acute care facilities. Three sources of data were used: 1998 American Hospital Association data, VHA External Peer Review Program data for 1998 and 1999, and the 1999 Veterans Satisfaction Survey. Organizational characteristics likely to affect adherence with the CPGs were classified into five conceptual domains (clinical emphasis, operational capacity, patient population, professionalism, and urbanicity). Organizational characteristics were ranked, based on their standardized beta coefficients in bivariate logistic regressions predicting the likelihood of adherence. Within-domain multivariable logistic analyses assessed the robustness of individual predictors of CPG adherence, controlling for other organizational factors within the same domain. RESULTS: Overall, 46 of 48 relationships in the bivariate logistic analyses were significant, and 43 of these remained significant in the within-domain multivariate analyses. The relative rankings of the variables as predictors of CPG adherence within conceptual domains were also quite consistent. CONCLUSIONS: Strong evidence was found for the importance of specific organizational factors, including mission, capacity, professionalism, and patient population characteristics that influence CPG adherence in a large multi-institutional sample involving multiple provider practices. Research and programs to improve adherence to CPGs and other quality improvement activities in hospitals should incorporate these organizational factors.

Alcoholism↗

PubMed1996

Mapping the Location of Prognostically Significant Microcirculatory Patterns in Ciliary Body and Choroidal Melanomas.

The microcirculation of choroidal and ciliary body melanomas is remodeled into architecturally distinctive patterns. The presence of two histologic microvascular patterns, networks and parallel vessels with cross-linking, is strongly associated with metastasis. This study was designed to test the hypothesis that networks and parallel vessels with cross-linking patterns are not distributed evenly throughout the tumor. From a set of 234 eyes removed for ciliary body or choroidal melanoma, 152 tumors contained at least one focus of either vascular networks or parallel vessels with cross-linking. Histological cross-sections were digitized and foci of tumor containing these patterns were pseudocolorized so that their location within the periphery or central tumor zone could be mapped. Ciliary body and choroidal melanomas vary widely in size and shape and it is not appropriate to describe the periphery of a tumor as a fixed value because in a small tumor, the periphery thus defined would occupy a larger percent area than in a larger tumor. In this study, the peripheral and central zones of each tumor were described by a function that was constant from tumor to tumor, allowing the width of the peripheral and central zones to vary proportionally with tumor size. Observed counts of vascular patterns per zone were compared statistically with expected counts based upon the percent area occupied by the peripheral and central zones. Discrete foci of networks and parallel with cross-linking vessels are over-represented in the tumor periphery (p < 0.0001).

Journal Article↗

PubMedDate not supplied

Depression in veterans of the first Gulf War and comparable military controls.

Depression is a common mental disorder associated with poor health outcomes. The purpose of this study is to examine the prevalence of depression, mental health comorbidity, illness variables, and quality of life in a sample of military veterans serving during the first Gulf War. The Iowa Gulf War Case Validation Study involved face-to-face evaluations in 1999--2002 of 602 military personnel--either deployed ("deployed veterans") or eligible but not deployed ("non-deployed veterans") to the Gulf. Subjects were sampled by conducting a series of case-control studies nested within a population-based survey of 4,886 military personnel. All subjects were interviewed using the Structured Clinical Interview for DSM-IV (SCID-IV), and a series of semi-structured interviews and validated questionnaires. Best estimate psychiatric diagnoses were assigned based on all available data. One-hundred-ninety-two (32%) of the 602 surveyed veterans met criteria for a current or lifetime depressive disorder (major depression, dysthymia, depressive disorder--not otherwise specified). Depressed non-deployed veterans were more likely to be female and to have served in the Air Force than depressed deployed veterans. There were few significant differences between the depressed deployed veterans and the depressed non-deployed veterans. Depressed deployed veterans had significantly higher lifetime rates of comorbid cognitive dysfunction (55% vs. 35%), and anxiety disorders (59% vs. 33%)--mainly accounted for by specific phobias (12% vs. 2%) and posttraumatic stress disorder (33% vs. 10%)--than did depressed non-deployed veterans. Lifetime substance use disorders were significantly more frequent in deployed veterans than non-deployed veterans (70% vs. 52%), particularly alcohol disorders (68% vs. 52%). There were no differences in rates of personality characteristics, family psychiatric history, stressors, hypochondriasis, and level of functioning between the two study groups showed no significant differences. Depressive illness is frequent in military samples, as it is in the general population. The prevalence, pattern of comorbidity, and illness features were similar in deployed veterans and non-deployed veterans, suggesting that the depression suffered by both groups of veterans is qualitatively comparable. The main difference between study, groups was that depressed deployed veterans had higher rates than depressed non-deployed veterans of comorbid anxiety disorders, hypothesized to be part of the stress-related syndromes seen in those who experience combat.

Adult↗

PubMedDate not supplied

Predictors of incident chronic widespread pain among veterans following the first Gulf War.

OBJECTIVE: We sought to determine the predictors of incident chronic widespread pain (CWP), specifically, the effect of preexisting symptoms, stress, and psychosocial factors in the subsequent development of CWP among veterans from the first Gulf War (GW). METHODS: We conducted a structured telephone survey (baseline) of military personnel originally from Iowa who were either eligible for or deployed to Operation Desert Shield/Desert Storm, approximately 5 years postconflict. We conducted a follow-up, clinical, in-person study of those who met a priori-defined outcomes of symptoms of cognitive dysfunction, depression, or CWP, and also a sample of those who did not meet any of the outcomes of interest. RESULTS: A total of 370 of 602 evaluated GW veterans were free of CWP 5 years postconflict. At follow-up, 69 (19%) of these had developed CWP. A positive family history of medically unexplained persistent symptoms [odds ratio (OR)=4.8 (2.3, 13.2)] was strongly associated with CWP. At baseline, individuals who reported preexisting symptoms of bronchitis [OR=4.9 (1.9, 12.3)] and cognitive dysfunction [OR=2.1 (1.1, 4.2)] were more likely to develop CWP. Alcohol use [OR=0.2 (0.1, 0.7)] was protective against CWP. Rather than combat-related exposure per se, the perception of stress at the time of the GW [OR=1.6 (1.1, 2.3)] correlated with CWP. DISCUSSION: Among the GW veterans evaluated longitudinally in this study, family history, predeployment symptoms, and the level of perceived stress during the GW were associated with subsequent development of CWP.

Adult↗

PubMedDate not supplied

Relationship between depression and pancreatic cancer in the general population.

OBJECTIVE: Prior research suggesting a relationship between pancreatic cancer and depression conducted on clinical populations has been subject to recall bias. We reexamined this association using longitudinal population-based data. METHODS: This was a retrospective cohort study using longitudinal insurance claims data. RESULTS: Men with mental disorders were more likely to develop pancreatic cancer than those without psychiatric claims (odds ratio 2.4, confidence interval 1.15-4.78). Depression more commonly preceded pancreatic cancer than it did other gastrointestinal malignancies (odds ratio 4.6, confidence interval 1.07-19.4) or all other cancers (odds ratio 4.1, confidence interval 1.05-16.0). CONCLUSIONS: Depression and pancreatic cancer are associated in the general population.

Adolescent↗

PubMedDate not supplied

Occurrence of cancer among people with mental health claims in an insured population.

OBJECTIVE: The objective of this research is to determine whether people with mental disorders are at increased risk for the subsequent development of malignancies compared with people without mental disorders. METHODS: This is a retrospective cohort study of administrative claims data. The study population included 722,139 adults who filed at least one medical claim from 1989 to 1993. The mental disorder cohort included people with a) one psychiatric hospitalization, b) one outpatient psychiatrist visit, or c) two outpatient mental health claims occurring at least 6 months before a cancer claim. The controls were subjects filing claims for medical services who had no mental health visits. We calculated age-stratified odds ratios (ORs) for development of malignancy. RESULTS: People with mental disorders were no more or less likely to develop a malignancy than those without after adjusting for age (women: OR, 1.03; 95% confidence interval [CI], 0.95-1.12; men: OR, 1.10; 95% CI, 0.97-1.24). People with mental disorders, however, developed cancer at younger ages and had increased odds of primary central nervous system tumors (women: OR, 2.12; 95% CI, 1.40-3.21; men: OR, 2.09; 95% CI, 1.22-3.59) and respiratory system cancers (women: OR, 1.57; 95% CI, 1.13-2.19; men: OR, 1.52; 95% CI, 1.09-2.12). CONCLUSIONS: Insured people with mental disorder claims had an increased risk of certain malignancies and developed malignancies at younger ages. The increased odds of respiratory tumors are likely secondary to increased rates of smoking among people with mental disorders and support use of smoking cessation interventions in this population. The increased odds for brain tumors may reflect only the early presence of mental symptoms, or a true association between the two conditions. Further study of these findings is mandated.

Adolescent↗

PubMedDate not supplied

Posttraumatic stress disorder and self-reported physical health status among U.S. Military personnel serving during the Gulf War period: a population-based study.

The objective of this study was to investigate the relation between posttraumatic stress disorder (PTSD) and perceived physical health. Participants included 3,682 Gulf War veterans and control subjects of the same era who completed a telephone survey about their health status. PTSD was assessed using the PTSD Checklist-Military Version. Veterans screening positive for PTSD reported significantly more physical health symptoms and medical conditions than did veterans without PTSD. They were also more likely to rate their health status as fair or poor and to report lower levels of health-related quality of life. The results of this study are consistent with studies of other combat veterans and provide further support for an association between PTSD and adverse physical health outcomes. Stressful or traumatic life events, such as those encountered during a rapid military deployment and conflict, are associated with a variety of adverse health effects. These health effects may manifest themselves in both psychological and physical outcomes. Health care providers must be attentive to recognize and evaluate both of these dimensions.

Adult↗