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D A Pollock

Publications and source records attributed to D A Pollock.

At least 37 records · Page 2Linked to original sources
PubMed1990

Estimating the number of suicides among Vietnam veterans.

Unconfirmed reports that 50,000 or more Vietnam veterans have committed suicide give the impression that these veterans are at exceedingly high risk of suicide compared with other veterans and nonveterans of the same age. On the basis of projections from two population-based mortality studies, the authors estimate that fewer than 9,000 suicides occurred among all Vietnam veterans from the time of discharge through the early 1980s. The sixfold or greater relative risk of suicide implied by the unsubstantiated suicide death tolls is also demonstrated to be incompatible with the findings of epidemiologic studies of mortality risk among Vietnam veterans.

Adult↗
PubMed1989

Trauma registries. Current status and future prospects.

Hospital trauma registries are evolving rapidly as a result of a renewed focus on trauma care evaluation and recent advances in microcomputer technology. In theory, trauma registries can serve as the principal tool for the systematic audit of the quality of patient care provided by a hospital or a trauma system and as a potential source of part of the data needed for injury surveillance. In practice, however, there is a tendency to underestimate the resources needed to initiate and maintain a registry. Herein, we describe the purposes, resource requirements, and limitations of trauma registries. We conclude that standardization of case criteria, core data content, data definitions, and coding conventions can enhance the utility of trauma registries.

Data Collection↗
PubMed1989

Validity of death certificates for injury-related causes of death.

Exploration of the validity of death certificate information for classifying underlying causes of death has historically focused on "natural" or disease-related causes of death. Current interest in injury-related deaths has emphasized the need for proper certification and coding of these deaths. In this study, the authors compared agreement of the underlying cause of death as determined from death certificate information with that determined from an independent review of all relevant medical and legal documents of death by a panel of physicians. The study sample included all deaths (n = 446) occurring over an approximately 18-year follow-up period (1965-1983) in a randomly selected cohort of 18,313 US Army Veterans of the Vietnam era. Using the physician panel as the "gold standard," sensitivity and specificity were 90% or greater for broad groupings of motor vehicle crash deaths (International Classification of Diseases, Ninth Revision (ICD-9), codes E810-E825), suicides (codes E950-E959), and homicides (codes E960-E969). Agreement for deaths from unintentional poisonings (codes E850-E869), mostly drug- and alcohol-related, was poor (sensitivity, 50 percent); in general, the ICD-9 drug- and alcohol-specific nomenclature is difficult to apply. The specificity and sensitivity for the individual three-digit suicide and homicide codes were all greater than 90%, and although the specificity for three-digit motor vehicle crash deaths was also above 90%, the sensitivity was lower, from 29% to 83%. Agreement on the fourth digit of ICD-9--for example, the role of the decedent in a motor vehicle crash death--was generally poor. The lack of descriptive information on death certificates to allow detailed coding was chiefly responsible for the poor agreement.

Adolescent↗
PubMed1989

A microcomputer program for coding external cause of injury.

The publication of Injury in America emphasized a renewed interest in the scientific study of trauma. Collection and analysis of population-based data were viewed as necessary prerequisites for the establishment and evaluation of injury prevention programs. While it was noted that there is an existing broad-based gathering of injury mortality information, it was also made clear that there is a paucity of systematically collected morbidity data. A fundamental step toward correcting this deficiency is to identify and adopt a uniform system for coding causes of injury morbidity that is compatible with the large body of mortality data currently being collected. This paper describes a microcomputer-based program, which is intended to aid in the selection of External Cause of Injury Codes (E-codes). It is designed for coding both fatal and nonfatal injury causes and is appropriate for use in the hospital setting. The system is a modification of the one currently used for coding all injury deaths in the United States.

Humans↗
PubMed1988

Antibiotic sensitivity of bovine staphylococcal and coliform mastitis isolates over four years.

Eight hundred and forty-eight strains of Staphylococcus aureus and coliforms isolated from milk samples taken from cows with clinical or subclinical mastitis were tested for their sensitivity to a range of antibiotics, comparing strains isolated in 1984, 1985, 1986 and 1987. The only increase in the proportion of resistant strains occurred with coliforms resistant to ampicillin and neomycin.

Animals↗
PubMed1987

Underreporting of alcohol-related mortality on death certificates of young US Army veterans.

We assessed the validity of death certificate data for alcohol-related mortality in a population-based follow-up study of young, male US Army veterans. In a random sample of more than 18,000 men who entered the service between 1965 and 1971, there were 446 postservice deaths through Dec 31, 1983. For 426 of these deaths, we obtained both the death certificate and all other available medical and legal records pertaining to cause of death. A nosologist recorded each death certificate in accordance with the ninth revision of the International Classification of Diseases. A medical panel, without having access to the death certificates, assigned underlying and contributory causes of death on the basis of a review of only the medical and legal records. The panel recorded 133 alcohol-related deaths, or more than six times the number (21 deaths) determined by the original death certifiers. Omission of elevated blood alcohol levels in deaths due to injury accounts for most of the underreporting of alcohol-related mortality on the death certificates. Our findings suggest that death certificate data grossly underestimate the contribution of alcohol to mortality, especially in the area of injury, and the validity of official vital statistics for alcohol-related deaths would be enhanced if death certifiers incorporated all available antemortem and postmortem diagnostic information.

Adult↗
PubMed1987

Phage typing of Staphylococcus aureus associated with subclinical bovine mastitis.

Six hundred and seventeen isolates of Staphylococcus aureus from subclinical clinical mastitis cases in 63 dairy herds in Northern Ireland were typed using a set of 25 phages. Ninety-four per cent of the isolates were typable, with nine phages, predominantly from groups I and III, being responsible for almost all of the lysis. Although 68 phage patterns were found, six of them typed 47.2% of the isolates. One strain accounted for 14.7% of the isolates, but the largest number of strains (44) was restricted to individual farms. The epidemiological significance of these findings for on-farm mastitis control is discussed.

Animals↗
PubMed1986

The loss of opsonic activity of bovine milk whey following depletion of IgA.

The role of the IgA antibody to Streptococcus agalactiae found in the whey of milks 12 hours after the first intramammary infection of six Friesian first lactation heifers was assessed using an in vitro bactericidal assay. The mean percentage kill of the streptococci by neutrophils in the presence of these wheys was 36.2% while the equivalent figure for the non-infected quarter whey was 0%. When the IgA antibody was absorbed from the infected quarter wheys using class specific IgA antiserum cross linked with glutaraldehyde the percentage kill of the test system fell to 0%. Elution of the absorbed antibody partially restored the activity to a mean percentage kill of 18.2%. The results indicated that the IgA antibody found in infected quarter whey during the acute stages of intramammary infection with Streptococcus agalactiae was responsible for the opsonic activity which pertained at that time.

Animals↗
PubMed1983

Clinical features of consecutive intramammary infections with Streptococcus agalactiae in vaccinated and non-vaccinated heifers.

The clinical, haematological and functional changes which followed three consecutive intramammary infections of Streptococcus agalactiae in the first lactation of eight heifers, four of which were systemically hyperimmune to the organism, are described. Irrespective of whether it was a vaccinated or non-vaccinated heifer or first, second or third infection the clinical features during the first 24 hours were characterised by elevated temperatures with hard, swollen and painful infected quarters. First infections were almost all of short duration because of self cure, while second or third infections were prolonged, with intermittent excretion of bacteria and low cell counts. Milk yields of infected quarters were depressed, ranging from 8 per cent in short infections to 31 per cent in chronic infections. All blood parameters remained within normal limits with the exception of total and differential white cell counts, which showed a change from a quantitative to a qualitative response by the third infection. The most significant finding was the absence of any real difference between the systemically hyperimmune and the non-vaccinated heifers, suggesting that circulating antibody has little effect against intramammary infection.

Animals↗
PubMed1982

Electron microscopic visualisation of the in vitro phagocytosis of group B streptococci by bovine polymorphonuclear leucocytes.

The phagocytosis of group B streptococci by bovine blood polymorphonuclear leucocytes, after 30 minutes at 37 degrees C, was visualised using scanning and transmission electron microscopy. Several polymorphonuclear leucocytes were seen to have phagocytosed more than one bacterium, despite the initial ratio of bacteria to cells being unity. All bacteria within the cells appeared to be viable and some were undergoing multiplication.

Animals↗
PubMedDate not supplied

Discrepancies in the reported frequency of cocaine-related deaths, United States, 1983 through 1988.

OBJECTIVE: --To assess the validity of cocaine-related mortality data available from the principal federal sources of information about the frequency of drug abuse deaths in the United States: the national vital statistics system and the Drug Abuse Warning Network (DAWN). DESIGN, SETTING, AND PARTICIPANTS: --We compared the number of cocaine-related deaths reported to national vital statistics and DAWN from 25 metropolitan areas during the years 1983 through 1988. We also compared cocaine-related mortality data reported to national vital statistics with data from all published forensic case series of cocaine-related deaths that occurred during the mid-1980s. RESULTS: --During the 6-year study period, 75% more cocaine-related deaths were reported to DAWN (6057) than to national vital statistics (3466) from the 25 metropolitan areas that were studied. For individual metropolitan areas, the discrepancy between DAWN and vital statistics counts of cocaine-related deaths was as large as a sixfold difference. In six of the seven forensic case series identified in our literature search, the number of cocaine-related deaths exceeded the number of these deaths reported to vital statistics. The largest discrepancy was for cocaine-related deaths in New York, NY, during a 10-month period in 1986 for which 151 deaths were reported in a case series and seven deaths were reported to vital statistics. CONCLUSION: --Improvements in existing public health surveillance systems are needed for (1) full and accurate measurements of the lethal impact of drug abuse epidemics and (2) valid and comprehensive assessments of the effectiveness of national programs designed to prevent drug-related morbidity and mortality.

Cause of Death↗