Biomedical subjects

Jeffrey D Dawson

Publications and source records attributed to Jeffrey D Dawson.

10 recordsLinked to original sources

PubMed2006

Unsafe rear-end collision avoidance in Alzheimer's disease.

Drivers with cognitive impairment are at increased odds for vehicular crashes. Rear-end collisions (REC) are among the most common crash types. We tested REC avoidance in 61 drivers with mild Alzheimer's disease (AD) and 115 elderly controls using a high-fidelity interactive driving simulator. After a segment of uneventful driving, each driver suddenly encountered a lead vehicle stopped at an intersection, creating the potential for a collision with lead vehicle or with another vehicle following closely behind the driver. Eighty-nine percent of drivers with AD had unsafe outcomes, either an REC or an risky avoidance behavior (defined as slowing down abruptly or prematurely, or swerving out of the traffic lane) compared to 65% of controls (P=0.0007). Crash rates were similar in AD (5%) and controls (3%), yet a greater proportion of drivers with AD slowed down abruptly (70% vs. 37%, P<0.0001) or prematurely (66% vs. 45%, P=0.0115). Abrupt slowing increased the odds of being struck from behind by the following vehicle (P=0.0262). Unsafe outcomes were predicted by tests of visual perception, attention, memory, visuospatial/constructional abilities, and executive functions, as well as vehicular control measures during an uneventful driving segment. Drivers with AD had difficulty responding to driving conditions that pose a hazard for a REC. Some cognitive and visual tests were predictive of unsafe outcomes even after adjusting for disease status.

Accidents, Traffic↗

PubMed2006

Iowa nursing home characteristics associated with reported abuse.

OBJECTIVE: To evaluate the association of nursing home abuse reported by employees in Iowa licensed nursing homes with nursing home characteristics, inspection results, nursing staff hours, and census demographics. DESIGN: Mailed survey. SETTING: Iowa's 409 Medicare-certified stand-alone nursing homes. PARTICIPANTS: Administrators and directors of nursing. RESULTS: The annual rate of abusive events was 20.7 per 1000 nursing home residents, with a rate of 18.4 reported events and 5.2 substantiated events. A higher number of residents and a higher number of certified beds were significantly associated with higher incident, report, and substantiation rates. Higher incident and report rates were associated with nursing homes in metropolitan areas. Higher substantiation rates were associated with for-profit nursing homes. CONCLUSION: Recognized abuse in nursing homes is not uncommon. Approximately 90% of events are reported to the state authorities with 29% of those being substantiated. Differences associated with nursing facility abuse rates are metropolitan area, ownership, occupancy rate, and number of residents and certified beds.

Aged↗

PubMed2006

Impaired visual search in drivers with Parkinson's disease.

OBJECTIVE: To assess the ability for visual search and recognition of roadside targets and safety errors during a landmark and traffic sign identification task in drivers with Parkinson's disease (PD). METHODS: Seventy-nine drivers with PD and 151 neurologically normal older adults underwent a battery of visual, cognitive, and motor tests. The drivers were asked to report sightings of specific landmarks and traffic signs along a four-lane commercial strip during an experimental drive in an instrumented vehicle. RESULTS: The drivers with PD identified significantly fewer landmarks and traffic signs, and they committed more at-fault safety errors during the task than control subjects, even after adjusting for baseline errors. Within the PD group, the most important predictors of landmark and traffic sign identification rate were performances on Useful Field of View (visual speed of processing and attention) and Complex Figure Test-Copy (visuospatial abilities). Trail Making Test (B-A), a measure of cognitive flexibility independent of motor function, was the only independent predictor of at-fault safety errors in drivers with PD. INTERPRETATION: The cognitive and visual deficits associated with PD resulted in impaired visual search while driving, and the increased cognitive load during this task worsened their driving safety.

Aged↗

PubMed2006

Relationship between physician knowledge of hypertension and blood pressure control.

The purpose of this study was to evaluate the cross-sectional relationship between physician knowledge of hypertension guidelines and blood pressure (BP) control. The authors evaluated a sample of primary care faculty (n=32) and a sample of their patients (n=613). When treating patients as independent observations, the authors found an inverse relationship (r=-0.524; p=0.002) where higher knowledge scores were associated with lower BP control. The authors conducted a multivariate analysis to accommodate the nonindependence due to random physician effects and found that there was no longer a significant association between knowledge and BP control, but there was still a trend (odds ratio=0.84; p=0.130). This study demonstrates that there is no evidence that high knowledge of hypertension guidelines will improve BP control rates and that higher knowledge may actually be associated with lower BP control. Strategies that are designed only to improve knowledge of hypertension guidelines are insufficient to improve BP control rates.

Adult↗

PubMed2005

APS workers job requirements associated with elder abuse rates.

The purpose of this paper is to evaluate the relationship of required educational background of APS workers to the 1999 rates of domestic elder abuse. Data were obtained from APS related statutes and regulations and questions to the National Center for Elder Abuse list serve. Descriptive statistics and independent sample t-tests were used for analyses. Those states whose legislations required a social work degree for APS caseworkers did have higher elder abuse investigation rates. A lower substantiation ratio was found for those states requiring a social work degree or license. These findings suggest that social work education may lead to an emphasis on investigation and interventions and de-emphasis on the criminal aspects of elder abuse evaluation substantiations.

Adult↗

PubMed2004

Quantitative analytical methods in translation research.

In research involving quality of health care, an intervention is often attempted at one or more institutions. This article presents the advantages and disadvantages of various study designs that might be considered for such institution-based research, looking at the issues of comparison groups, replication, blocking, and contamination. Three examples illustrate the importance of accommodating the lack of independence or clustering that occurs among subjects within an institution, and show how these accommodations for clustering can sometimes be made by applying basic statistical techniques to institution-level outcomes, whereas at other times more sophisticated approaches are necessary.

Analysis of Variance↗

PubMed2003

Community characteristics associated with child abuse in Iowa.

PROBLEM: Various demographic and community characteristics are associated with child abuse rates in national and urban samples, but similar analyses have not been done within rural areas. This study analyzes the relationships between reported and substantiated rates of child abuse and county demographic, health care resource and social services factors in a predominantly rural state in the US. METHODS: County-level data from Iowa between 1984-1993 were analyzed for associations between county characteristics and rates of child abuse using univariate correlations and multivariate stagewise regression analysis. Population-adjusted rates of reported and substantiated child abuse were correlated with rates of children in poverty, single-parent families, marriage and divorce, unemployment, high-school dropouts, median family income, elder abuse, birth and death rates, numbers of physicians and other healthcare providers, hospital, social workers, and number of caseworkers in the Department of Human Services. RESULTS: Rates of single-parent families, divorce and elder abuse were significantly associated with reported and substantiated child abuse in multivariate analysis, while economic and most health care factors were not. Reporting and substantiation rates differed across districts after adjustment for multiple factors including caseworker workload. CONCLUSIONS: In this rural state, family structure is more significantly associated with child abuse report and substantiation rates than are socioeconomic factors. The level of health care resources in a county does not appear to affect these rates.

Adolescent↗

PubMed2003

Domestic elder abuse and the law.

OBJECTIVES: The authors evaluated the impact of state adult protective service legislation on rates of investigated and substantiated domestic elder abuse. METHODS: Data were collected on all domestic elder abuse reports, investigations, and substantiations for each US state and the District of Columbia for 1999. State statutes and regulations pertaining to adult protective services were reviewed. RESULTS: There were 190 005 domestic elder abuse reports from 17 states, a rate of 8.6 per 1000 elders; 242 430 domestic elder abuse investigations from 47 states, a rate of 5.9; and 102 879 substantiations from 35 states, a rate of 2.7. Significantly higher investigation rates were found for states requiring mandatory reporting and tracking of numbers of reports. CONCLUSIONS: Domestic elder abuse documentation among states shows substantial differences related to specific aspects of state laws.

Aged↗

PubMed2002

Complete imputation of missing repeated categorical data: one-sample applications.

Longitudinal studies with repeated measures are often subject to non-response. Methods currently employed to alleviate the difficulties caused by missing data are typically unsatisfactory, especially when the cause of the missingness is related to the outcomes. We present an approach for incomplete categorical data in the repeated measures setting that allows missing data to depend on other observed outcomes for a study subject. The proposed methodology also allows a broader examination of study findings through interpretation of results in the framework of the set of all possible test statistics that might have been observed had no data been missing. The proposed approach consists of the following general steps. First, we generate all possible sets of missing values and form a set of possible complete data sets. We then weight each data set according to clearly defined assumptions and apply an appropriate statistical test procedure to each data set, combining the results to give an overall indication of significance. We make use of the EM algorithm and a Bayesian prior in this approach. While not restricted to the one-sample case, the proposed methodology is illustrated for one-sample data and compared to the common complete-case and available-case analysis methods.

Algorithms↗

PubMed2002

Non-evidence-based use of Rho(D) immune globulin for threatened abortion by family practice and obstetric faculty physicians.

OBJECTIVE: To examine the practice patterns and differences between faculty members in obstetrics and gynecology (OB/G) and family practice (FP) residency programs in administering Rho(D) immune globulin (RhIG) for threatened abortion. STUDY DESIGN: A questionnaire was mailed to 50% (222) of all FP residencies and 100% (267) of OB/G programs in the United States. The obstetric curriculum coordinator at each FP residency and the director of obstetrics or maternal-fetal medicine at each OB/G residency were asked to respond. A total of 156 (70%) FP questionnaires and 186 (70%) OB/G questionnaires were returned after two mailings. RESULTS: Seventy-six percent of FP faculty and 85% of OB/G faculty reported giving RhIG in threatened abortion. Physicians with advanced training were more likely to recommend giving RhIG. CONCLUSION: Most FP and OB/G residency faculty report using RhIG in threatened abortion. The practice has become part of the medical culture despite the lack of supporting evidence and should be revaluated in that light.

Abortion, Threatened↗