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H M Baum

Publications and source records attributed to H M Baum.

At least 19 recordsLinked to original sources

Conducting clinical trials in a constantly changing health care environment.

Continuous change and cost containment characterize the current health care system, making conduct of clinical trials and other clinical research difficult. Identification, accrual, and follow-up of patients who move between health care environments such as hospitals, nursing homes, schools and the home is particularly challenging. This article describes a circuit rider approach to patient identification and follow-up that was established by the Communication Sciences and Disorders Clinical Trials Research Group. It also gives suggestions for design of clinical trials in a constantly changing environment.

Alzheimer Disease↗

Initiating a clinical trials cooperative group in an increasingly managed care environment: successes and problems in establishing collaboration.

The Communication Sciences and Disorders Clinical Trials Research Group (CSDRG) was organized in 1995 and funded in 1997 by the National Institute on Deafness and Other Communication Disorders (NIDCD) as a cooperative clinical trials group. It designs and conducts multi-institutional randomized clinical trials focusing on treatments delivered by speech-language pathologists (SLPs) and audiologists for disorders of speech, language, hearing, balance, and voice/swallowing. Data are presented on a comparison of the number of site participants from the group's onset in 1995 through 31 December 1997. Successes and problems experienced by CSDRG are defined with regard to organizing the group, and designing and conducting clinical trials in a managed care environment with nonprimary care professionals. Different barriers to participation are identified at various levels of care/types of institutions and with various types of patient populations, for example, children receiving their health care through the schools versus elderly, demented individuals in nursing care facilities.

Audiology↗

Tractor-trailer crashes in Indiana: a case-control study of the role of truck configuration.

Studies of the crash experience of tractors pulling multiple trailers have reached different conclusions concerning the relationship of truck configuration to crash risk. A previous case-control study found a significant increase in crash risk for double-trailer trucks in the state of Washington. The present case-control study was done of tractor-trailers crashing on Indiana interstates during November 1989-March 1991. Controls were obtained for 25% of the crash sites and were all tractor-trailers passing the crash sites during a traffic observation session one to four weeks following a crash on the same day of the week for 30 minutes at the same time of day. Logistic regression identified day of week, time of day, urban/rural area, and specific highway as significant predictors of controls' truck configuration. This model was applied to the cases to estimate the expected number of double-trailer cases. For all crashes combined, no increased crash risk was observed for doubles (Standardized Crash Ratio (SCR) = 83). Doubles were significantly underinvolved in multiple-vehicle crashes (SCR = 74), crashes on dry roads (SCR = 61), and crashes on wet (other than snow, ice, or slush) roads (SCR = 54). Doubles were significantly overinvolved in crashes on roads with snow, ice, or slush (SCR = 153). Because truck configuration was highly associated with driver age and work operation attributes among trucks in crashes, the absence of control data on these potential confounders precluded definitive assessment of the intrinsic risk of multiple versus single-trailer vehicles.

Accidents, Traffic↗

Long hours and fatigue: a survey of tractor-trailer drivers.

Fatigue and long driving hours have been implicated as risk factors in truck crashes. Under federal regulations, commercial drivers are permitted to drive no more than 10 hours before having an 8-hour break and cannot work more than 70 hours over an 8-day period. Several studies have suggested that violations of these rules are common. A survey of long haul tractor-trailer drivers was conducted to estimate what proportion of drivers report that they regularly violate the hours-of-service rules and to identify the drivers most likely to commit hours-of-service violations. During December 1990 through April 1991, a total of 1,249 drivers were interviewed at truck safety inspection stations, truck stops, and agricultural inspection stations in Connecticut, Florida, Oklahoma, and Oregon. In each state, interviews were conducted during varying periods of the day over the course of seven days at inspection stations. Overall, 89 percent of eligible drivers asked for interviews participated in the survey. According to self-reports, almost three-fourths of the respondents violate hours-of-service rules. About two-thirds of the drivers reported that they routinely drive or work more than the weekly maximum. A primary impetus for violating rules appears to be economic factors, including tight delivery schedules and low payment rates. Many other driver, job, and vehicle characteristics were significantly associated with being an hours-of-service violator. The high prevalence of hours-of-service violations among tractor-trailer drivers is a problem in need of urgent attention. Potential measures to reduce the prevalence of rules violations include more enforcement directed toward carriers, wider use of electronic recorders, and increasing the number of rest areas.

Accidents, Traffic↗

Comparisons of the thoracic trauma index with other models.

The thoracic trauma index (TTI) provides an indication of the severity of injuries received by motor vehicle occupants in side-impact collision environments. The index was derived from results on two sets of cadaver tests. Using a variety of statistical and numerical methods, the authors reanalyzed the data from these 80+ cadaver tests to construct a better measure of injury than TTI. Indices generated by these analyses were compared with TTI using the following quantitative measures: monotonicity, overlap, percentage correct, and sensitivity. The values of these measures are broadly similar for all indices and none of the new indices consistently performs better than TTI. This suggests that TTI is as good a predictor of injury as any of the several alternative models created.

Accidents, Traffic↗

The mortality consequences of raising the speed limit to 65 mph on rural interstates.

As of April 1987, states were permitted to raise the speed limit on rural interstates to 65 mph without incurring federal sanctions; 38 states elected to do so in 1987. Fatality data for the months when the new limit was in effect in 1987 were compared with fatalities in the same months of 1982-86 on rural interstates and other rural roads. Fatalities on rural interstates in the states with increased speed limits in 1987 were conservatively estimated to be 15 percent higher than they would have been if the states had retained the 55 mph limit (95% CI = 6, 24). Among states that retained the 55 mph limit, fatalities on rural interstates were 6 percent lower than expected (95% CI = -23, 13).

Accidents, Traffic↗

Referral bias in multiple sclerosis research.

Referral bias is a significant problem affecting the generalizability of clinical studies conducted in a university setting. To examine referral bias in our university-based multiple sclerosis referral center, we analyzed the characteristics of referral center patients compared to the population-based group of multiple sclerosis patients from which the referral center patients originated. The referral center patient group differed from those that remained in the population-based group in the following important ways: (1) they were younger, (2) they had more mobility impairment for their age, (3) disabled females were overrepresented compared to disabled males, (4) they more often reported recent disease worsening, (5) they had a higher frequency of early diagnosis supported by laboratory tests, and (6) they more often relied on neurologists and therapists for routine care of their disease. The multiple sclerosis referral center setting would appear to be ideal for the conduct of intervention trials, but inadequate for collecting representative natural history data.

Activities of Daily Living↗

Employment in individuals with multiple sclerosis.

The major objectives of this research were to examine unemployment in the MS population on a national level, and to identify factors which might influence an MS individual's employment status. Data used were from the National Multiple Sclerosis Survey conducted by the National Institute of Neurological and Communicative Disorders and Stroke. Data analysis was restricted to a subset of the sample who had worked at some time in their lives. Of 949 persons 79.7% were currently unemployed. While 65.2% had worked at the time of first symptom, only 27.2% were working at the time of the interview, an average of 17 years later. Path analyses revealed the overwhelming importance of mobility for remaining employed, particularly for males. Additional differences found between male and female path models were interpreted in terms of social role theory.

Disability Evaluation↗

Higher than expected prevalence of multiple sclerosis in northern Colorado: dependence on methodologic issues.

A population-based study of multiple sclerosis (MS) was conducted in 2 northern Colorado counties in 1982 to determine MS prevalence, to compare the rates with recent North American surveys and to compare the methods used in these studies. Provisional cases were identified from: the patient rolls of MS service organizations, chart reviews in 2 neurology practices, a survey of physicians and a review of hospital discharge diagnoses. Crude-point prevalence for the 2-county region was 84 per 100,000. The age-adjusted rate was higher than the rate for the region above the 37th parallel projected from data in a 1976 national survey, but was comparable to rates obtained in localized surveys conducted in the northern tier of the country. The methodological results revealed that the highest yield sources were the MS service organizations and the neurology practice chart reviews. MS prevalence surveys which neglect these methods may underestimate MS prevalence by as much as 20-40%.

Adult↗

Multiple sclerosis and mobility restriction.

Examination of mobility restriction among multiple sclerosis (MS) patients and its relationship to selected disease and demographic characteristics was undertaken using data gathered in the National Multiple Sclerosis Survey. Whether and where an individual needed assistance and the types of assistance needed were the dependent variables. These data were crosstabulated with the following patient characteristics: sex, race, educational level, region of residence, age on prevalence day, marital status, awareness of diagnosis, diagnostic code, duration of disease and age at first diagnosis. More than half of the patients reported needing assistance both indoors and outdoors. Significant factors in increasing the percentage needing assistance were as follows: longer duration, older at the time of first diagnosis, admitted awareness of the diagnosis, currently unmarried, nonwhite, and a "probable" MS diagnostic code. Most patients relied on a wheelchair or a person's assistance for help while few relied on crutches or leg braces.

Adult↗

The incidence and prevalence of reported multiple sclerosis.

A national survey, sponsored by the National Institute of Neurological and Communicative Disorders and Stroke, to determine the incidence, prevalence, and economic impact of multiple sclerosis has just been completed. These data are the first report of the results. Based on the data gathered, it is estimated that on January 1, 1976, there were a reported 123,000 multiple sclerosis patients in the conterminous United States (a rate of 58 per 100,000). The annual incidence for the period 1970-1975 was estimated to be 8,800 (a rate of 4.2 per 100,000). The pattern of the disease being more common among females, whites, persons aged 30-50 years, and individuals living above the 37th parallel was also demonstrated. In addition to demographic characteristics, selected disease characteristics of the incidence and prevalence populations were also examined.

Adult↗