Biomedical subjects

S M Rock

Publications and source records attributed to S M Rock.

9 recordsLinked to original sources

PubMed1998

Impact from changes in Illinois drivers license renewal requirements for older drivers.

In late 1989, Illinois revised the length of license term and renewal requirements for older drivers. The term was shortened from 4 to 2 years for those ages 81-86 and 1 year for those ages 87 and up. A mandatory road test which had been required at renewal for all drivers ages 69 and over, was eliminated for those ages 69 to 74. Data are available to explore the impact of these changes on crashes, fatal crashes, crash rates, and licensure rates of senior drivers. Comparisons are made between 1987-1989 averages and 1995 for three age groups: 70-74, 75-80 (the control group that had no changes in requirements), and 81 and up. It does not appear that eliminating the road test for those ages 69 to 74 had any negative impact. On the contrary, it does not appear that the more frequent renewal period for those ages 81 and up produced any benefit compared to the control group. As the number of older drivers continue to increase into the future, the analysis of licensing requirements and their impact is important.

Accidents, Traffic↗

PubMed1996

Impact of the Illinois child passenger protection act: a retrospective look.

This paper considers the Illinois child restraint use law which took effect in July 1983. This law requires parents to use safety seats for children under age 4, and seat belts or safety seats for those aged 4 or 5. ARIMA time series models and a monthly data set of fatalities and injuries from 1980 through 1986 were utilized. The law reduced the total number of children under 5 killed or injured in traffic crashes by 10% along with a 17% decline in the number of child injuries per crash. No spillover effect was found for older children.

Accidents, Traffic↗

PubMed1995

Impact of the 65 mph speed limit on accidents, deaths, and injuries in Illinois.

At the end of April 1987, Illinois raised the speed limit from 55 to 65 mph on rural interstates and limited-access highways. This paper examines the effects of this change. It applies ARIMA techniques to a monthly time series of accidents, injuries, and fatalities dating from five years before the limit increase to four years after. Two types of rural highways are examined: those where the speed limit was raised and those where it remained at 55 mph. The impact of higher limits on mean speeds, speed variance, traffic diversion, traffic generation, speed spillover, and issues of benefits and costs are considered. The findings suggest the higher limit led to 300 additional accidents per month in rural Illinois, with associated increases in deaths and injuries. This impact was apparent on both 65 and 55 mph roads. There is some evidence of traffic diversion from 55 to 65 mph highways plus traffic generation and speed spillover.

Accidents, Traffic↗

PubMed1994

Birth outcomes to rural Illinois residents: is there a crisis?

In recent years, the supply of obstetric services in rural areas has been a concern. At the same time, the demand for such services has been affected by the reduction in population and economic base. This article explores the extent of these trends in Illinois and whether they have led to a deterioration in amount of prenatal care and birth outcomes. Using birth certificate and infant death data for residents of rural Illinois counties in 1983 and 1988, prenatal care and birth outcomes for each year are compared within rural areas and to the rest of the state, as well as between the two time periods. Although rural residents began prenatal care later, they obtained similar qualities of care as their urban counterparts. The data revealed no adverse impact on birth outcomes of residing in increasingly rural areas, nor was there a deterioration during the time period. An attempt was made to identify rural counties that lost providers and/or facilities and those that gained them. Although such a classification scheme is subjective, similar results ensued. While indirect costs such as time and effort to obtain care may have increased, at 1988 levels of care availability there was no crisis in Illinois.

Data Collection↗

PubMed1993

Risk compensation and the Illinois seat belt use law.

The question of whether drivers alter their behavior due to vehicle safety improvements or public policy changes (laws, enforcement) has been debated for some years. The possibility of risk compensation (offsetting behavior) has been offered: drivers may go faster or operate in a less safe manner in response to such a change. Three 1991 publications purportedly find risk compensation due to mandatory seat belt use laws. However, these conclusions are questionable due to the weaknesses in statistical methods that were used (before/after comparisons, regression). This paper examines whether risk compensation occurred due to the 1985 use law in Illinois. It also compares the results of the before/after method to a preferred technique (ARIMA, developed by Box and others). These approaches are applied to monthly totals and rates of fatalities, injuries classified by level of severity, and total accidents from 1980-1991. Three types of accident are analyzed: vehicle/pedestrian, vehicle/bicycle, and all others. If nonoccupants have suffered adverse consequences, risk compensation could provide the explanation. Much less evidence of offsetting behavior was found. No statistically significant increase in accidents occurred. While other types of safety changes may alter driver behavior, this did not seem to occur in Illinois due to the belt use law.

Accidents, Traffic↗

PubMed1991

Right ventricular myocardial infarction.

Right ventricular myocardial infarction (RVMI) is recognized as an important clinical entity. The clinical course of patients with RVMI may be benign, or it may progress to profound hypotension and cardiogenic shock. The medical and nursing management of these patients differs significantly from that of patients with left ventricular infarction. The nurse must be familiar with the clinical signs and medical treatment of RVMI to facilitate early diagnosis and to plan appropriate acute and long-term nursing management of these patients.

Electrocardiography↗

PubMedDate not supplied

A sophisticated electromechanical ventricular simulator for ventricular assist system testing.

With the advent of chronically implanted left ventricular assist systems, new adaptive control algorithms are being developed to allow automatic device control under a variety of hemodynamic conditions. An electromechanical pump is described that accurately mimics ventricular function. A pusher-plate sac pump with tri-leaflet valves is coupled to a high-speed linear motor. Pump chamber volume and pressure are constrained to follow the time-varying elastance model of ventricular function by use of a microprocessor feedback loop.

Computer Simulation↗

PubMedDate not supplied

Malpractice premiums and primary cesarean section rates in New York and Illinois.

The fear of malpractice liability is mentioned frequently as a cause of increased cesarean section rates, but without quantitative investigations. This perception may be studied at an aggregate level by comparing malpractice insurance premiums, a proxy for liability risk, with primary cesarean section rates. Both New York and Illinois are divided into territories for insurance rates; the premium was uniform within each territory over the period studied for each specialty. Premiums for obstetricians were linked to birth and procedure data from New York and Illinois hospitals for 1981 and 1983, respectively, to determine whether there was a correlation between premium levels and the primary cesarean section rate. A statistically significant difference was found between mean cesarean rates by insurance premium territories in each State. A correlation was observed between increased insurance rates among territories and increased cesarean section rates. Based on these results, a substantial impact was found on delivery decisions resulting from the fear of malpractice suits.

Cesarean Section↗

PubMedDate not supplied

Variability and consistency of rates of primary and repeat cesarean sections among hospitals in two states.

Hospitals in New York and Illinois have wide variations in their primary and repeat cesarean section rates. A number of factors account for these differences. To investigate whether hospitals with higher or lower rates tend to continue these patterns over time, their rates in 1988 were compared with those in 1983. It was found that a hospital's cesarean section rate was consistent, but some regression to the mean process did occur. By 1988, teaching hospitals had lower rates than nonteaching hospitals; this difference is likely due to the greater response to calls for increasing trials of vaginal birth after a previous cesarean section by teaching hospitals. Over time this should contribute to further moderating of the rates. Data were from the Illinois and New York State Departments of Health.

Cesarean Section↗