Biomedical subjects

K B Stevens

Publications and source records attributed to K B Stevens.

9 recordsLinked to original sources

PubMed2005

Factors associated with the wastage and achievements in competition of event horses registered in the United Kingdom.

The aims of this study were to estimate the wastage of horses registered for eventing in Britain, to investigate the reasons for this wastage and to evaluate factors affecting the horses' achievement of grade I status (at least 61 points) while registered. An analysis of the database of the British Eventing register found that 33.7 per cent of horses registered for the first time in 1999 were not re-registered for eventing in subsequent years. By using multivariable logistic regression analysis, it was shown that horses that were kept at an event yard were more likely to be re-registered than those kept on other premises (odds ratio [or] 2.0, 95 per cent confidence interval [ci] 1.2 to 3.2), and those that took part in showjumping while registered were also more likely to be re-registered (or 1.5, 95 per cent ci 1.1 to 2.2). Horses that took part in unaffiliated eventing while registered were less likely to be re-registered the following year (or 0.7, 95 per cent ci 0.5 to 0.9), as were those that were not insured (or 0.7, 95 per cent ci 0.5 to 1.0) and those from outside the British Isles (or 0.6, 95 per cent ci 0.3 to 1.0). Veterinary problems were the most commonly cited explanation (35.1 per cent) why horses that remained in their original ownership were not re-registered with British Eventing the following year. Horses from Australia were more likely to achieve grade I status than horses from the British Isles (or 9.7, 95 per cent ci 7.1 to 13.2), as were horses from New Zealand (or 6.4, 95 per cent ci 5.0 to 8.2), the usa (or 5.2, 95 per cent ci 3.8 to 7.2) and France (or 2.8, 95 per cent ci 2.1 to 3.7), but horses from the Netherlands (or 0.5, 95 per cent ci 0.3 to 0.9) and Belgium (or 0.3, 95 per cent ci 0.1 to 0.9) were less likely to achieve grade I status. Mares were less likely to achieve grade I status than geldings (or 0.4, 95 per cent ci 0.4 to 0.5).

Animals↗

PubMed2005

Clinical and clinicopathological changes in 6 healthy ponies following intramuscular administration of multiple doses of imidocarb dipropionate.

Haematological variables and selected serum indices, particularly those affected by changes in renal and hepatic function, were examined in 6 healthy ponies following 4 intramuscular doses of 4 mg/kg imidocarb dipropionate administered every 72 hours. This treatment regime has been reported to sterilise experimental Babesia equi infections in horses and may have value in preventing the spread of this disease during exportation of possible carrier horses to non-endemic countries. Serum bile acids and serum gamma glutamyltransferase activity were measured to evaluate the effect of this treatment regime on hepatic function. Owing to the absence of any increase in these variables it was concluded that this treatment regime had no clinically detectable deleterious effect on hepatic function in healthy ponies. Urinary gamma glutamyltransferase : creatinine ratios (IU/g), serum creatinine and fractional clearance of sodium, potassium and phosphate (%) were calculated as a measure of renal function. Urinary GGT and urinary GGT : creatinine ratios were significantly elevated on Day 5 of the trial, with 2 of the trial animals also exhibiting mild azotaemia indicative of changes in renal function. The changes in urine GGT : urine creatinine ratios observed in this study also provides evidence of the value of this ratio for the early detection of renal toxicity, following exposure to nephrotoxic agents.

Animals↗

PubMed2003

Equine hepatic disease: the effect of patient- and case-specific variables on risk and prognosis.

REASONS FOR PERFORMING STUDY: Liver disease is fairly common in horses and, although previous literature suggests that fatality rates are high, impressions gained from current clinical practice suggest that this is no longer the case. OBJECTIVES: A case-control study was undertaken in 2 hospitals to investigate whether age, gender or breed type predisposed horses to developing hepatic disease, with the additional aim of determining whether these factors and disease category had any effect on outcome. METHODS: Eighty-eight cases were identified by review of computerised archives at 2 hospitals. Three cases admitted immediately before and after the cases were used as controls. Multivariant models were developed to explore the relationship between age, breed type and gender and the development of liver disease, and within the clinical cases, to identify whether any of these factors or specific forms of liver disease were associated with fatality rate. RESULTS: Ponies were more likely to develop hepatic disease than light riding horses, but neither age nor gender were significant risk factors. Overall, the fatality rate was fairly low; horses with unclassified hepatopathies had the lowest fatality rate and those with cholangiohepatitis, pyrrolizidine alkaloid toxicity and chronic active hepatitis had significantly higher fatality rates in comparison. However, age, breed type and gender had no detectable effect on outcome. CONCLUSIONS AND POTENTIAL RELEVANCE: Such data could be of particular value to equine practitioners, as the cases were drawn from both primary and referral practice, and were all seen within the last 5 years.

Age Factors↗

PubMed1999

Adult reading assessment: are we doing the best with what we have?

This article describes a survey completed by 728 neuropsychologists for the purpose of gathering information about the assessment of reading in adults as part of neuropsychological examinations. The survey information gathered addressed (a) the general frequency of assessing adult reading, (b) the assessment tools used, (c) the general purposes for the assessment of reading, (d) the need for a review describing available adult reading norm-referenced tests, and (e) the need for the development of criterion-referenced reading tests appropriate for determining functional reading abilities. Survey findings are reported and discussed. A list and description of reading tests appropriate for assessing reading in adults also is provided in the Appendix.

Achievement↗

PubMed1999

The circumstances surrounding the outbreak and spread of equine influenza in South Africa.

Equine-2 influenza A virus (H3N8) infection first occurred among naïve horses in South Africa in December 1986. The virus was introduced following the importation of six horses from the United States of America. While the release of in-contact horses from quarantine three days after the arrival of these six horses played a role in the rapid spread of the disease in South Africa, other outbreaks of disease were associated with viral introduction by personnel or contaminated instruments. The control measures and implications of the introduction of equine influenza to South Africa are also discussed.

Animals↗

PubMed1998

Etiology of acute gastroenteritis in hospitalized children in Melbourne, Australia, from April 1980 to March 1993.

Acute infectious diarrhea is common in children. Control requires knowledge of causes. Few comprehensive long-term studies of etiology have been undertaken in developed countries. This report is of a 13-year survey of 4,637 children from 0 to 14 years of age, admitted to a large children's hospital for treatment of gastroenteritis, in which viruses, bacteria, and parasites were sought. A recognized enteric pathogen was identified in 56.6% of children. Group A rotaviruses occurred in 39.6% of children overall and in 55% of children 12 to 23 months of age. They were a frequent cause (18.7%) of acute gastroenteritis in children under 6 months and in those aged 5 to 13 years (16%). Rotaviruses were almost entirely responsible for winter admission peaks. Enteric adenovirus types 40 and 41 (6% overall) were more frequent in children under 12 months (9.4%). Salmonella spp. (5.8%) and Campylobacter jejuni (3.4%) were more common in children over 5 years (13.1% and 6.7%, respectively). The 43.5% of cases (60% in children under 6 months) where no enteric pathogen was identified are cause for concern. The involvement of small viruses (including caliciviruses and astroviruses) may be clarified when molecular biology techniques are utilized to address this gap in our knowledge. This comprehensive 13-year study of the cause of acute infectious diarrhea in children in developed countries reinforces the importance of rotavirus and highlights a large group for whom the etiology remains unknown, an issue of particular concern with babies under 6 months of age. New techniques have the potential to identify old and new pathogens causing disease in these vulnerable infants.

Acute Disease↗

PubMed1997

Response bias in plaintiffs' histories.

This study investigated response bias in self-reported history of factors relevant to the assessment of traumatic brain injury, toxic brain injury and related emotional distress. Response bias refers to systematic error in self-report data. A total of 446 subjects (comprising 131 litigating and 315 non-litigating adults from five locations in the United States) completed a symptom questionnaire. Data were obtained from university faculty and students, from patients in clinics specializing in physiatry neurology, and family medicine, and from plaintiffs undergoing forensic neuropsychological evaluations. Comparisons were made for litigant and non litigant ratings of their past and current cognitive and emotional functioning, including life in general, ability to concentrate, memory, depression, anxiety, alcohol, drugs, ability to work or attend school, irritability, headaches, confusion, self-esteem, and fatigue. Although there is no basis for hypothesizing plaintiffs to be healthier than the general population, plaintiffs rated their pre-injury functioning superior to non-plaintiffs. These findings suggest that response biases need to be taken into account by forensic examiners when relying on litigants' self-reports of pre-injury status.

Adult↗

PubMed1997

Psycholegal implications of malingered head trauma.

In this article we examine the roles of individuals involved in traumatic head injury claims. These roles are described in terms of their integrated affects on one another, the outcome of the claim, and ultimately, society. Particular focus is on the role of the neuropsychologist as diagnostician, therapist, expert witness, and consultant; however, the roles of the plaintiff, the defendants, the attorneys, the judges, and juries also are addressed. The costs for invalid claims are high and ultimately fall on society in terms of higher health care costs, insurance premiums, and taxes. Because of this impact on society, the responsibility of neuropsychologists who diagnose, treat, and serve as expert witnesses and consultants in head injury claims cannot be underestimated.

Journal Article↗

PubMed1991

Teaching memorized spelling with a microcomputer: time delay and computer-assisted instruction.

A computer-assisted instruction program was evaluated that used a constant time-delay procedure to teach 5 students 18 spelling words. In addition to delivering the instructional procedure, the program managed the presentation of training content based on individual student responding and collected instructional data on individual student performance. The procedure was effective at teaching 4 of the 5 students the words, and generalization occurred from the computer-delivered keyboard response format to a teacher-delivered hand-written response format. Maintenance data varied among the students. The study demonstrated the feasibility of using microcomputers to deliver time-delay instruction in special education classrooms and suggested several research questions related to specific features of microcomputer-delivered time-delay instruction.

Achievement↗