PubMed HealthSearch

Biomedical subjects

T Haines

Publications and source records attributed to T Haines.

12 recordsLinked to original sources

Workplace organizational correlates of lost-time accident rates in manufacturing.

We report the results of a questionnaire survey of manufacturing workplaces related to the lost-time frequency rates (LTFR) for Workers' Compensation claims. Six types of industry were chosen.' metal articles, plastic articles, grain products, textile manufacturing, printing, and automobile manufacturing. LTFR were standardized by type of industry. Stratifying simultaneously by number of employees and LTFR category, we sampled 718 workplaces. A mail questionnaire to labor and management representatives provided at least some information on 58%. Response rates were similar across LTFR categories, and telephone interviews of non-responders showed little difference in their replies from those obtained in completed questionnaires. A large number of variables were examined. Apart from statistical significance, we looked for consistency in trends across LTFR categories and in patterns for similar questions. Significant associations grouped into several areas. Lower LTFR were associated with: concrete demonstration by management of its concern for the workforce; greater involvement of workers in general decision-making; greater willingness of the Joint Health and Safety Committee to solve problems internally; and greater experience of the workforce. Variables that were not significant included profitability and financial performance. A final stepwise multiple regression explained 19% of the variance in LTFR, although this analysis suffered from several limitations.

Absenteeism

Dexamethasone treatment for acute bacterial meningitis: how strong is the evidence for routine use?

A methodological appraisal of the published randomised controlled trials on the use of dexamethasone as an adjunct treatment in acute bacterial meningitis was carried out to examine whether the available evidence is strong enough to support the routine use of the drug. Studies were eligible for inclusion if they were published in indexed journals after 1966, written in English, and were randomised controlled trials with dexamethasone as adjunct to antimicrobials in patients with acute bacterial meningitis. All studies were extracted and their adherence to eight methodological principles was graded as adequate, inadequate, or unclear. A sensitivity analysis was done to examine the robustness of the conclusions. Seven studies met the eligibility criteria. No report adhered to all the principles. Major threats to validity of the conclusions included potential bias in analysis in all the studies, and lack of adjustment for baseline imbalances in four. Inadequate reporting of adverse effects hindered risk-benefit analysis. Sensitivity analysis showed that the numbers of patients withdrawn from analysis were enough to invalidate the conclusions. It is concluded that the available evidence is not strong enough to support a routine use of dexamethasone in acute bacterial meningitis. Further research is needed to determine the effect of a policy to use dexamethasone early in the management of suspected acute bacterial meningitis. Future studies should adopt a pragmatic approach, be methodologically rigorous, and meticulously measure the risk as well as the benefit of this policy.

Acute Disease

A study of sister chromatid exchange and somatic cell mutation in hospital workers exposed to ethylene oxide.

To investigate the risks of exposure to ethylene oxide (EO) at current permissible levels and at past higher levels, an inception cohort of sterilizer operators and supervisors from the Central Processing Department (CPD), respiratory therapists, and engineers exposed to EO were identified at the McMaster University Medical Centre. A comparison group from Nutrition Services (NUTR) were matched with the CPD workers on the basis of sex, age, and smoking habit. The present report is based on genetic test results for the 94 CPD and matched NUTR workers only. Statistical analysis based on the mean SCE frequency in the top 5, top 10, and all cells (50 cells scored per individual) and high frequency cells (HFC) based on the 95th percentile for nonsmoking control subjects showed a direct association with current smoking but not with EO exposure. Similarly, statistical analysis of the somatic cell mutation (SCMT) variant frequencies did not demonstrate an association with EO exposure, nor with smoking. Regression analysis indicated that sex was the only other covariate that significantly affected SCE. Age was weakly associated with SCMT. A statistically significant interaction between occupational exposure and smoking habits was observed only for the mean SCE frequency of the top 5 and top 10 cells when the 11 current CPD/NUTR pairs were not included. Thus, this interaction should be interpreted with caution.

Ethylene Oxide

Postlaryngectomy quality-of-life dimensions identified by patients and health care professionals.

We compared the quality-of-life (QOL) dimensions after laryngectomy in patients with advanced larynx or pharynx cancer that were elicited from 20 consecutive laryngectomy patients and 20 health care professionals working in the Regional Head and Neck Oncology Service. Subjects in both groups were asked to identify important QOL items after recovery from laryngectomy and to rank and rate each on a vertical visual analogue scale. Health care professionals ranked impaired communication and self-image/self-esteem as the two most important QOL dimensions, whereas patients ranked the physical consequences of surgery, e.g., tracheal mucous production, and interference with social activities as the two most important items. The results indicate that the responses of health care professionals do not fully correlate with patient priorities. These findings are relevant to researchers developing treatment-specific QOL measures and to health care professionals when presenting treatment options to patients.

Adult

Concordance of occupational and environmental exposure information elicited from patients with Alzheimer's disease and surrogate respondents.

Identification of risk factors for Alzheimer's disease through the use of well designed case-control studies has been described as a research priority. Increasing recognition of the neurotoxic potential of many industrial chemicals such as organic solvents raises the question of the occupational and environmental contribution to the etiology of this high-priority health problem. The intention of this study was to develop and evaluate a methodology that could be used in a large scale case-control study of the occupational and environmental risk factors for dementia or a population-based surveillance system for neurotoxic disorders. The specific objectives of this study were to investigate: 1) the reliability of exposure-eliciting, interviewer-administered questionnaires given to patients with Alzheimer's disease (SDAT); 2) the reliability of exposure-eliciting interviewer-administered questionnaires given to the family of patients with SDAT and the agreement with the responses of the patient or surrogate respondents; 3) the reliability and agreement of responses of age- and sex-matched control patients and their families selected from geriatric care institutions and the community, with respect to the same exposure-eliciting and interviewer-administered questionnaire; and 4) the reliability of agent-based exposure ascertainment by a single, trained rater. The results of the study demonstrate that occupational and environmental histories from which exposure information can be derived is most reliably elicited from job descriptions of cases and control subjects rather than job titles alone or detailed probes for potential neurotoxic exposures. This will necessitate the use of standardized interviewer-administered instruments to derive this information in case-control studies of Alzheimer's disease or population-based surveillance systems for occupational and environmental neurotoxicity.

Alzheimer Disease

Cancer morbidity in lamp manufacturing workers.

A historical prospective study of cancer in lamp manufacturing workers in one plant was conducted. All men and women who worked for a total of at least 6 months and were employed at some time between 1960 and 1975 were included. Work histories were abstracted and subjects were divided according to whether they had worked in the coiling and wire drawing area (CWD). Cancer morbidity from 1964 to 1982 was ascertained via the provincial registry, and was compared with the site-specific incidence in Ontario, adjusting for age, sex and calendar period. Of particular interest were primary breast and gynecological cancers in women. The cancers of a priori concern were significantly increased in women in CWD, but not elsewhere in the plant. The excess was greatest in those with more than 5 yr exposure (in CWD) and more than 15 yr since first working in CWD, with eight cases of breast and gynecological cancers observed in this category compared with 2.67 expected. Only three cancers occurred in men in CWD. Environmental measurements had not been made in the past and little information was available on substances used in the 1940s and 1950s, the period when the women with the highest excess began employment. It is known that methylene chloride and trichlorethylene have been used, but not enough is known about the dates and patterns of use to draw any conclusions about their relationship with the increase in disease.

Breast Neoplasms

Workers' perceptions, knowledge and responses regarding occupational health and safety: a report on a Canadian study.

This paper presents data from interviews with 492 rank and file workers. It examines aspects of workers' perceptions, knowledge and actions regarding workplace hazards and views these as indicators of the potential strength of labour in improving occupational health and safety. Respondents had a strong consciousness of ways in which their work might damage their health and they or their fellow workers had experienced half of the symptoms they mentioned. However, they lacked information on the results of environmental and medical monitoring, their core legal rights and the more effective strategies for reducing hazards. Few respondents sought information and few were persistent in dealing with their worries about hazards. Knowledge of their rights under the current occupational health and safety legislation was linked with taking such actions. It is suggested that workers' pursuit of their health and safety concerns might be facilitated if they had better access to information about their legal rights and mechanisms for dealing with hazards in the workplace.

Accidents, Occupational

Aesthesiometric threshold changes over the course of a workshift in miners exposed to hand-arm vibration.

The objective of this study was to investigate whether aesthesiometric threshold changes occur over the course of a workshift in vibration exposed hard rock miners relative to workers unexposed to vibration during the shift. The subjects were 99 miners and 40 smelter workers; four subjects declined to participate and nine were excluded from the analysis because of apparent failure to comprehend the testing procedure. Two point discrimination and depth sense aesthesiometry were conducted at the beginning and at the end of the workshift in all digits of both hands excluding the thumbs. In addition to the use of a vibrating tool during the shift, age, digital temperature, signs of arm injury, presence of fingertip callus, and handedness were documented. In the analysis the difference between postshift and preshift readings was studied in relation to these variables, particularly exposure to the jackleg drill during the shift. With the exception of exposure of the jackleg drill, no associations were observed between these variables and change over the workshift in aesthesiometric results, on both unadjusted comparison of means and backward elimination regression analysis. A statistically significant association, however, was found between the use of a jackleg drill and change in two point discrimination and in depth sense aesthesiometric results over the course of the shift, for the right hand. Evidence of the occurrence of a learning effect, particularly for two point discrimination aesthesiometry, was observed. The occurrence of an effect in the right, but not the left, hand reflects dominant handedness and relatively greater vibration exposure in the right hand in our subjects. This study supports the incorporation of an exposure free interval before aesthesiometric testing of vibration exposed workers.

Fingers

Peripheral neurological assessment methods for workers exposed to hand-arm vibration. An appraisal.

Peripheral neurological assessment methods for workers exposed to hand-arm vibration have included vibration perception and esthesiometric threshold testing, electroneurography, handgrip force, and manipulative dexterity. For epidemiologic investigations with the purpose of detecting vibration effects anticipated as moderate to large in size in occupational populations, these methods have demonstrated their usefulness. Concerning their value in the assessment of individual workers, there is little quantitative information, as there have been no studies which have conducted rigorous "gold standard" neurological evaluation with which the results of independently performed diagnostic tests can be compared. However, results from four papers which used depth-sense (or ridge) and two-point discrimination esthesiometry were available for an analysis of the sensitivity of these tests in the detection of Taylor-Pelmear stages 2 and 3 of the hand-arm vibration syndrome. With specificity set at 90%, sensitivity ranged from 45 to 96% for depth-sense esthesiometry and from 19 to 75% for two-point discrimination. In addition, likelihood ratios were determined, as a measure of the capacity of the tests to alter pretest probability of disease. Because of their direct clinical interpretation and application, the use of likelihood ratios is suggested for future research on diagnostic methods used for vibration-exposed workers.

Arm

Sample size in occupational mortality studies.

In 1980, the Occupational Safety and Health Administration asserted that "non-positive human studies" would be considered in reviews of evidence only if in a study the "group of exposed subjects was large enough for an increase in cancer incidence of 50% above that in unexposed controls to have been detected at any of the predicted sites." The concepts of statistical testing and power in occupational mortality studies are reviewed, and studies published in two prominent occupational health journals in 1979 and 1980 are analyzed in terms of their power. A large proportion of standardized mortality ratio studies have a low probability of detection of relative risks of the order of 1.5.

Epidemiologic Methods