Biomedical subjects

D Sorenson

Publications and source records attributed to D Sorenson.

7 recordsLinked to original sources

PubMed2000

Demographic differences in body composition of Navy and Marine Corps personnel: findings from the perception of wellness and readiness assessment.

With the recent increase in women's representation in the military, baseline physical measurement data are needed to help set appropriate accession and retention standards and to design useful prevention and intervention programs in the areas of physical fitness and health. This study incorporated several body composition indices to obtain anthropometric data for a representative sample of 1,292 active duty Navy and Marine Corps women and men. It also assessed the extent to which personnel met weight-for-height and body fat standards. The prevalence of overweight was considerably lower among Marine Corps women compared with Navy women and was slightly less for Marine Corps men compared with their Navy counterparts. Between one-fifth and one-third of military personnel exceeded Navy/Marine Corps weight-for-height standards. Navy women tended to meet weight standards more often than Navy men. Fewer Marine Corps women than men were overweight, but more exceeded their weight-for-height standards.

Adipose Tissue↗

PubMed1997

New computer-based tools for empiric antibiotic decision support.

Since 1995 we have been developing a decision-support model, called Q-ID, which uses a series of infectious disease knowledge bases to make recommendations for empirical treatment or to check the appropriateness of current antibiotic therapy. From disease manifestations and risk factors, a differential diagnosis for the patient is generated by a diagnostic medical expert system. The resulting probability of each: disease is multiplied by the expected benefit in improved mortality and morbidity from optimal antibiotic treatment of each disease. To generate empirical treatment recommendations, site-specific data on sensitivity to antibiotics of each organism is used as an estimate of the likelihood of achieving maximum benefit for each disease on the patient's differential. Combining this data with drug and patient specific factors, the model recommends the antibiotic(s) most likely to produce the optimal benefit in this patient with the least risk and expense. In this paper the model is described, excerpts from each of the knowledge bases are presented, and performance of the model in a real case is shown for illustration.

Aged↗

PubMed1996

Qualitative analysis of temporal information in Iliad: implications for linking Iliad to an electronic medical record as a knowledge server.

In linking Iliad to an electronic medical record (EMR) as a knowledge server, our objective is to convert the date and time stamped data from the EMR to the temporal representations existing in the Iliad knowledge base. First, an empirical analysis of Iliad's temporal information content is described: categorizing, estimating the amount (22%), and offering a temporal template to canonically represent it. Second, we analyze the effect of history and physical examination temporal information on the diagnostic performance of the system using data from 241 real cases. Third, we discuss knowledge engineering mapping techniques to convert time information found in EMRs. We conclude that the Iliad system includes a large amount of explicit and implicit time information and this information improves the system's diagnostic accuracy, both in terms of diagnosis ranking and confidence.

Artificial Intelligence↗

PubMed1993

Implementation of practice guidelines in a clinical setting using a computerized knowledge base (Iliad).

We present the implementation of the indications for surgery for three surgical operations--cholecystectomy, cataract extraction, and knee arthroscopy--in a medical expert system, called Iliad. This implementation operates in the preauthorization service of IHC Health Plans (an insurance company in Salt Lake City) as a basis for reimbursement of services. Patient data collection forms, derived from Iliad knowledge base, were used by 13 participating surgeons to document the objective patient observations that justify the surgery and, then were faxed to IHC where a trained nurse input the data in Iliad. Iliad's decisions and reports on any deviations from guidelines are communicated back to the care provider. The study evaluates the impact of the computerized implementation on process, as measured by a questionnaire, and on outcome as measured by rate of approvals, documentation level, rate of requests, and average cost. The prospective implementation of the computerized guidelines has performed reliably, has been perceived as a preferred alternative to the old preauthorization system, and, most importantly, has enhanced significantly the level of documentation permitting evaluation and determination of appropriateness before surgery.

Arthroscopy↗

PubMed1991

Iliad training enhances medical students' diagnostic skills.

Iliad is a computerized, expert system for internal medical diagnosis. The system is designed to teach diagnostic skills by means of simulated patient case presentations. We report the results of a controlled trial in which junior students were randomly assigned to received Iliad training on one of two different simulated case mixes. Each group was subsequently tested in both their "trained" and "untrained" case domain. The testing consisted of computerized, simulated patient cases for which no training feedback was provided. Outcome variables were designed to measure the students' performance on these test cases. The results indicate that students made fewer diagnostic errors and more conclusively confirmed their diagnostic hypotheses when they were tested in their trained domain. We conclude that expert systems such as Iliad can effectively teach diagnostic skills by supplementing trainees' actual case experience with computerized simulations.

Clinical Clerkship↗

PubMed1987

A role for glucocorticoids in the polyphosphoinositide second messenger system.

Glucocorticoids have been shown to be involved in numerous secretory and activation processes which are known to be mediated by the polyphosphoinositide second messenger system. A connection between glucocorticoids and the polyphosphoinositide system has not been made because of the marked temporal differences in their effects and the fact that most of the known effects of glucocorticoids involve transcription and/or protein synthesis. An attempt is made to to rationalize these apparent incongruities. The recently reported stimulation of glucose transport by kinase C suggests an experimental system to investigate glucocorticoid effects on the polyphosphoinositide system.

Calcium↗

PubMed1981

An adventitious role of cortisol in degenerative processes due to decreased opposition by insulin: implications for aging.

Cortisol can be implicated as contributing to a number of degenerative processes including arteriosclerosis, atherosclerosis, diabetes, and deterioration of muscle and the immune system. These effects of cortisol are amplified in diabetes due to a diminished opposition by insulin. In addition, this phenomena may not be restricted to diabetes. There is evidence that tissue sensitivity to insulin generally decreases with age, although insulin levels and metabolism may remain constant; this is not generally true for cortisol. This results in an increased cortisol activity with some pathological consequences which are most evident in vascular connective tissue and the immune system. The decrease in tissue responsiveness to insulin with respect to cortisol may reflect relative aging differences in the corresponding receptor-effector systems.

Aging↗