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T Haines

Publications and source records attributed to T Haines.

17 recordsLinked to original sources
PubMed2006

Watershed nitrogen and mercury geochemical fluxes integrate landscape factors in long-term research watersheds at Acadia National Park, Maine, USA.

This paper is an overview of this special issue devoted to watershed research in Acadia National Park (Acadia NP). The papers address components of an integrated research program on two upland watersheds at Acadia NP, USA (44 degrees 20' N latitude; 68 degrees 15' E longitude). These watersheds were instrumented in 1998 to provide a long-term foundation for regional ecological and watershed research. The research was initiated as part of EPA/NPS PRIMENet (Park Research and Intensive Monitoring of Ecosystems Network), a system of UV-monitoring stations and long-term watershed research sites located in US national parks. The initial goals at Acadia NP were to address research questions about mercury, acid rain, and nitrogen saturation developed from prior research. The project design was based on natural differences in forests and soils induced by an intense wildfire in one watershed in 1947. There is no evidence of fire in the reference watershed for several hundred years. We are testing hypotheses about controls on surface water chemistry, and bioavailability of contaminants in the contrasting watersheds. The unburned 47-ha Hadlock Brook watershed is 70% spruce-fir mature conifer forest. In contrast, burned 32-ha Cadillac Brook watershed, 4 km northeast of the Hadlock watershed, is 20% regenerating mixed northern hardwoods and 60% shrub/rocky balds. Differences in atmospheric deposition are controlled primarily by forest stand composition and age. The watersheds are gauged and have water chemistry stations at 122 m (Cadillac) and 137 m (Hadlock); watershed maximum elevations are 468 and 380 m, respectively. The stream water chemistry patterns reflect, in part, the legacy of the intense fire, which, in turn, controls differences in forest vegetation and soil characteristics. These factors result in higher nitrogen and mercury flux from the unburned watershed, reflecting differences in atmospheric deposition, contrasting ecosystem pools of nitrogen and mercury, and inferred differences in internal cycling and bioavailabilty.

Acid Rain↗
PubMed2005

Medicinal and injection therapies for mechanical neck disorders.

BACKGROUND: Medicinal therapies and injections are commonly recommended for neck pain, yet controversy persists over their effectiveness. OBJECTIVES: To determine the effect of medicines and injections on pain, function/disability, patient satisfaction and range of motion in participants with mechanical neck disorders (MND). SEARCH STRATEGY: We searched CENTRAL (Issue 4, 2002), and MEDLINE, EMBASE, MANTIS, CINHAL from their start to March 2003. We scrutinized reference lists for other trials. SELECTION CRITERIA: We included randomized controlled trials with adults with MND, with or without associated headache or radicular findings. We considered medicinal and injection therapies, regardless of route of administration. DATA COLLECTION AND ANALYSIS: Two authors independently selected articles, abstracted data and assessed methodological quality using the Jadad criteria. Consensus was used to resolve disagreements. When clinical heterogeneity was absent, we combined studies using random-effects meta-analysis models. MAIN RESULTS: We found 32 trials that examined the effects of oral NSAIDs, psychotropic agents, injections of steroids, and anaesthetic agents. Overall, methodological quality had a mean of 3.2/5 on the Jadad Scale. For acute whiplash, administering intravenous methylprednisolone within eight hours reduced pain at one week, and sick leave but not pain at six months compared to placebo. For chronic MND at short-term follow-up, intramuscular injection of lidocaine was superior to placebo or dry needling, but similar to ultrasound. In chronic MND with radicular findings, epidural methylprednisolone and lidocaine reduced neck pain and improved function at one-year follow-up compared to the intramuscular route. In subacute/chronic MND, we found conflicting evidence of pain reduction for oral psychotropic agents compared to placebo or control. Single trials of eperison hydrochloride and tetrazepam showed positive results. Results for cyclobenzaprine were mixed. Diazepam did not show benefit. Other treatments including NSAIDS and nerve blocks had unclear or limited evidence of benefit. In participants with chronic MND with or without radicular findings or headache, there was moderate evidence from five high quality trials showing that Botox A intramuscular injections were not better than saline in improving pain (pooled SMD: -0.39 (95%CI: -1.25 to 0.47), disability or global perceived effect. AUTHORS' CONCLUSIONS: Intra-muscular injection of lidocaine for chronic MND and intravenous injection of methylprednisolone for acute whiplash were effective treatments. There was limited evidence of effectiveness of epidural injection of methylprednisolone and lidocaine for chronic MND with radicular findings. Oral psychotropic agents had mixed results. There was moderate evidence that Botox A intramuscular injections for chronic MND were no better than saline. Other medications, including NSAIDs, had contradictory or limited evidence of effectiveness.

Anesthetics, Local↗
PubMed2002

Manual therapy for mechanical neck disorders: a systematic review.

Neck disorders are common, disabling and costly. Randomized trials were reviewed using a Cochrane format, to determine if manual therapy improves pain, function and patient satisfaction in adults suffering from neck disorders with and without radicular findings or headache. Sequenced computerized searches ended in December 1997. Two independent reviewers extracted data while three assessed trial quality. Standard mean difference and relative risks were translated to number needed to treat (NNT) and the percent treatment advantage. The 20 selected trials' quality was 2.4 (SD: 1.04) on the 5-point scale described by Jadad. Trials were clinically heterogenous. Manipulation alone, mobilizations alone, manipulation/mobilization and treatments including massage consistently showed similar effects to placebo, wait period or control. Multimodal manual therapy care including exercise were superior to a control, to certain physical medicine methods and to rest for pain and patient satisfaction. The NNT for a clinically important reduction in pain varied from 2 to 11 and treatment advantage from 6% to 41% at the cost of benign transient side-effects. While results remain inconclusive, some clinical themes have emerged. For mechanical neck disorder with or without headache, it appears that to be most beneficial, manual therapies should be done with exercise for improving pain and patient satisfaction. Manipulation and mobilization alone appear to be less effective. Factorial design would help delineate the magnitude of effect for each component of care.

Adult↗
PubMed2001

A critical appraisal of review articles on the effectiveness of conservative treatment for neck pain.

STUDY DESIGN: A criteria-based appraisal of review articles on neck pain. OBJECTIVES: To assess the methodologic quality, conclusions, and extent of concordance among reviews on the conservative treatment of neck disorders. SUMMARY OF BACKGROUND DATA: During the past decades there has been an increasing interest in summarizing and analyzing the available evidence on the effectiveness of conservative management of neck pain. Considering the growing number and quality of reviews, consumers may question which reviews to read and believe. METHODS: Computerized bibliographic databases were searched without language restriction. The reviews assessed had been published before January 1998, included neck pain and evaluated conservative therapies, and reported at least one controlled clinical trial. Identification, selection, and quality assessment were performed independently by two investigators. RESULTS: Of the 108 identified articles, 25 review articles were selected, of which 12 were systematic reviews. The reviews differed in their reporting of study population, interventions, and outcomes. Statistical pooling was performed in two high-quality systematic reviews, whereas in other reviews, the investigators explicitly decided not to pool data. The results of the current study show that the concordance among reviews varied. Regarding manipulation and traction, there is inconclusive evidence among reviews. Concordance regarding the effectiveness of other conservative interventions was absent. Many of the reviews displayed major methodologic flaws. CONCLUSIONS: Consumers should consider reports of reviews both carefully and critically, given the wide variety of review methodology, descriptive information, and final conclusions. There is a paucity of evidence from primary studies on neck pain. Therefore, more research is needed to allow systematic reviews to formulate stronger conclusions.

Databases, Bibliographic↗
PubMed2001

Assessment of hand-arm vibration syndrome in a northern Ontario base metal mine.

The objective of this study was to determine the prevalence of hand-arm vibration syndrome (HAVS) in 617 workers at a base metal mine in northern Ontario. Workers who were employed at the mine between the years 1989 and 1994 and who continued to live within a 100 km radius of the mine were sent a self-reported questionnaire to identify individuals with possible vibration-induced symptoms in their upper extremities. Of the 162 workers who attended the medical examination, 50% were diagnosed with HAVS, 26% had other diagnoses with some workers having multiple afflictions e.g., both HAVS and carpal tunnel syndrome (CTS). No vibration-induced symptoms were reported in 35% of the workers who were clinically normal. The study was designed to educate, advise, and to make recommendations on the prevention of HAVS. Ongoing commitments to technological improvements, mandatory and regular rest periods, and continuing educational sessions on the syndrome should help to reduce the prevalence of this disease.

Adult↗
PubMed1996

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↗
PubMed1995

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↗
PubMed1993

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↗
PubMed1992

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↗
PubMed1989

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↗
PubMed1988

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↗
PubMed1988

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↗
PubMed1988

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↗
PubMed1987

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↗
PubMed1983

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↗