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1.
Ergonomics ; 64(11): 1369-1378, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34190679

RESUMO

The Revised Strain Index (RSI), a model that quantifies physical exposure from individual hand/wrist exertions, tasks, and multi-task jobs, was used to quantify exposure for 1372 incident-eligible manufacturing, service and healthcare workers. Workers were followed for an average of 2.5 years (maximum 6 years) and had an average carpal tunnel syndrome (CTS) incidence rate of 4.6 per 100 person-years. Exceeding the a-priori RSI limit of 10.0 showed increased risk of CTS (Hazard Ratio (HR) = 1.45, 95% CI: 1.11-1.91, p = 0.01). There also was a dose-response relationship using proposed low (RSI ≤ 8.5, HR = 1.00), medium (HR = 1.42 (95% CI: 0.96-2.09, p = 0.08)), and high limits (RSI > 15, HR = 1.79 (95% CI: 1.19-2.69, p = 0.01), respectively. RSI as a continuous variable showed CTS risk increased steadily by between 1.9% and 3.3% per unit increase in RSI (p ≤ 0.03). These results suggest that the RSI is a useful tool for surveillance as well as for job intervention/design and continuous improvement processes.Practitioner Summary The Revised Strain Index (RSI) quantifies physical exposure from individual hand/wrist exertions, tasks, and multi-task jobs. Increased cumulative RSI scores (i.e. daily exposure score) are associated with increased risk of carpal tunnel syndrome (CTS). The RSI is potentially useful as a risk surveillance and intervention design tool.


Assuntos
Síndrome do Túnel Carpal , Doenças Profissionais , Síndrome do Túnel Carpal/epidemiologia , Síndrome do Túnel Carpal/etiologia , Estudos de Coortes , Humanos , Doenças Profissionais/epidemiologia , Doenças Profissionais/etiologia , Ocupações , Estudos Prospectivos , Fatores de Risco
2.
Horm Behav ; 125: 104804, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32531397

RESUMO

Hyperprolactinemia is an endocrine disorder associated with infertility in many species, including elephants. In a recent survey of zoos accredited by the Association of Zoos and Aquariums (AZA), over half of African elephant females (N = 101) were not cycling normally, 30% of which exhibited hyperprolactinemia. We examined whether life experience and temperament predict ovarian cyclicity and circulating prolactin status in individual African elephant females. We hypothesized that, similar to humans, acyclicity and hyperprolactinemia in elephants will be associated with an apprehensive or fearful, anxious temperament, and an increased number of potentially challenging life events (transfers, deaths and births). Ninety-five adult African elephant females housed at 37 AZA institutions were included in this study. Blood samples were collected twice a month for 1 year to determine ovarian cycle (cycling, n = 44; irregular, n = 13; non-cycling, n = 38) and prolactin (normal, n = 44; low; n = 23; high; n = 28) status. Keeper ratings on a 6-point scale were obtained on 32 temperament traits in 85 of these elephants. We determined that giving birth and being exposed to herd mates entering the facility were positively associated with normal ovarian cycle and prolactin profiles. By contrast, age, serum cortisol, and an increased number of herd mates leaving a facility were negatively associated with both. Contrary to our hypothesis, hyperprolactinemia was associated with a popular and caring temperament rating, whereas consistently low prolactin was associated with a fearful, apprehensive temperament. These findings indicate that pituitary-ovarian function may be impacted by life history (cyclicity) and temperament (prolactin), which should be taken into consideration when making management decisions.


Assuntos
Animais de Zoológico/fisiologia , Elefantes/fisiologia , Ciclo Estral/fisiologia , Características de História de Vida , Prolactina/sangue , Temperamento/fisiologia , Animais , Animais de Zoológico/sangue , Elefantes/sangue , Ciclo Estral/sangue , Feminino , Humanos , Hiperprolactinemia/sangue , Hiperprolactinemia/veterinária , Masculino , América do Norte , Ovário/fisiologia , Periodicidade , Hipófise/fisiologia , Gravidez
3.
Nicotine Tob Res ; 22(9): 1439-1445, 2020 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-32034908

RESUMO

INTRODUCTION: The looming vulnerability model holds that people become anxious when they perceive threats as growing larger and accelerating toward them in space and time. Preliminary research suggested that a guided imagery induction designed to activate a sense that health consequences of smoking are a looming threat led more smokers to attempt to quit. This study tested the effect on quit attempts in a larger sample and examined age, sex, and sensation seeking as moderators. AIMS AND METHODS: Adult smokers (≥10 cigarettes/day) screened for risk of anxiety or mood disorders (N = 278, 52% male; 77% African American) were randomly assigned to receive (1) looming vulnerability or (2) neutral guided imagery exercises. At a 4-week follow-up, they reported quit attempts, smoking rate, self-efficacy, outcome expectancies, and contemplation status. RESULTS: Those in the looming condition (17%) were no more likely than those in the control condition (20%) to make a quit attempt. There were no significant group differences in expectancies, contemplation, or follow-up smoking rate, and no significant moderators. CONCLUSIONS: The looming induction was the same one used in earlier work in which it had stronger effects. Those who respond to it with increased urgency about quitting smoking might be offset by others who are more reactant and deny the message. Inconsistencies across studies may reflect differences in inclusion criteria, such that the present sample was on average heavier smokers with longer smoking history and more severe nicotine dependence, yet higher self-efficacy. IMPLICATIONS: An induction designed to activate a sense that the health consequences of smoking constitute a looming vulnerability failed to increase quit attempts or reduce smoking rate among adult daily smokers. Inconsistencies across studies might reflect varying sample characteristics resulting from changes in screening criteria.


Assuntos
Etnicidade/psicologia , Fumantes/psicologia , Dispositivos para o Abandono do Uso de Tabaco/estatística & dados numéricos , Abandono do Uso de Tabaco/métodos , Tabagismo/terapia , Populações Vulneráveis/estatística & dados numéricos , District of Columbia/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Autoeficácia , Abandono do Uso de Tabaco/psicologia , Tabagismo/epidemiologia , Tabagismo/psicologia , Populações Vulneráveis/psicologia
4.
J Clin Psychol ; 71(7): 641-52, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25846982

RESUMO

OBJECTIVE: Treatment outcome was compared among non-Hispanic White and racial/ethnic minority participants with trichotillomania (TTM), or hair-pulling disorder. METHOD: Symptom severity, quality of life, and TTM-related disability were compared in a behavior therapy trial with a stepped care approach: web-based self-help and then individual behavior therapy. The sample comprised 72% (n = 38) non-Hispanic White participants and 28% (n = 15) minority participants. RESULTS: The ethnic groups responded differently to treatment, with fewer minority participants showing improvement during web-based self-help. Response rates were equivalent between ethnic groups during the in-person behavior therapy. These results should be interpreted with caution because of the small sample size of minorities in the study and consequent inability to analyze results for each racial/ethnic group individually. CONCLUSIONS: Future studies should focus on the investigation of factors that may enable or hinder racial and ethnic minority participants to benefit from online and/or self-help behavior therapy for TTM.


Assuntos
Terapia Comportamental/métodos , Etnicidade/etnologia , Resultado do Tratamento , Tricotilomania/etnologia , Tricotilomania/terapia , População Branca/etnologia , Feminino , Humanos , Internet , Masculino , Autocuidado/métodos
5.
Am J Ind Med ; 57(3): 286-302, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24243166

RESUMO

BACKGROUND: This study's objective was to quantify exposure-response relationships between job physical exposure (JPE) and incidence of lateral epicondylitis (LE). METHODS: A cohort of 536 workers was enrolled from 10 manufacturing facilities and followed monthly for 6 years to ascertain changes in JPE and health status. JPE was individually measured and quantified using the Strain Index (SI) and TLV for HAL. Worker demographics, medical history, psychosocial factors, and current musculoskeletal disorders were obtained. RESULTS: Fifty-six workers developed LE. In multivariate models JPE, age, family problems, and swimming were associated with increased risk of LE. SI showed an exposure-response relationship with maximum hazard ratio (HR) of 4.5(P = 0.04). TLV for HAL showed a non-statistically significant trend for increased risk of LE (P = 0.19). CONCLUSION: JPE is associated with increased risk of LE. The SI and TLV for HAL are useful metrics for estimating JPE.


Assuntos
Transtornos Traumáticos Cumulativos/epidemiologia , Indústrias , Doenças Profissionais/epidemiologia , Exposição Ocupacional/estatística & dados numéricos , Cotovelo de Tenista/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Estudos de Coortes , Ergonomia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Prospectivos , Natação , Wisconsin/epidemiologia , Adulto Jovem
6.
Bull Menninger Clin ; 88(1): 81-99, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38527102

RESUMO

Prior studies of behavior therapy for trichotillomania (TTM) have shown that response is variable, and relapse after treatment discontinuation is common. Little information is available concerning prognostic factors capable of predicting individual differences in response or maintenance of improvement. The present study is a secondary analysis of a randomized controlled trial (N = 36) of the Comprehensive Behavioral (ComB) model of treatment for TTM (Carlson et al., 2021). We investigated age, disorder history, pre-treatment symptom severity, longest prior period of abstinence from pulling, and Emotion and Intention hair pulling styles as predictors of initial response. We studied age, disorder history, pre-treatment symptom severity, longest prior period of abstinence from pulling, and post-treatment symptom severity or hair-pulling abstinence as predictors of relapse following treatment. Older age significantly predicted lower TTM severity following treatment. Lower pre-treatment severity significantly predicted lower severity of TTM at the 3-month follow-up.


Assuntos
Tricotilomania , Humanos , Tricotilomania/terapia , Emoções , Terapia Comportamental , Recidiva
7.
Gen Comp Endocrinol ; 189: 7-14, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23623777

RESUMO

African elephants in US zoos are not reproducing at replacement levels. This is in part due to physiological problems, one of which is abnormal ovarian cyclicity that has been linked to increased prolactin secretion (hyperprolactinemia). A relationship between increased estrogen production (hyperestrogenism) and hyperprolactinemia has been found in other species. Therefore, the objective of this study was to determine if elevated prolactin was associated with increased estrogen concentrations in non-cycling African elephants. In cycling elephants (n=12), prolactin secretion followed a normal cyclic pattern, with higher concentrations observed during the follicular phase; overall mean concentration was ∼18ng/ml and baseline prolactin was ∼6ng/ml. Non-cycling females (n=18) were categorized into three groups: (1) low prolactin (<15ng/ml; n=3); (2) moderate hyperprolactinemia (16-30ng/ml; n=7); and marked hyperprolactinemia (>31ng/ml; n=8). Mean urinary estrogen conjugate concentrations ranged from 5.4 to 41.4ng/mg Crt, and were similar between normal cycling (15.4±1.5ng/mg Crt) and non-cycling, low prolactin elephants (18.4±7.3ng/mg Crt), but were lower in moderate (9.4±1.3ng/mg Crt) and marked hyperprolactinemic (9.8±1.1ng/mg Crt) groups (P<0.05). In conclusion, African elephants appear to be sensitive to alterations in prolactin production, with both low (e.g., a non-cycling pattern) and high prolactin secretion being associated with abnormal ovarian activity. However, hyperestrogenism was not related to hyperprolactinemia in the non-cycling females.


Assuntos
Estrogênios/sangue , Hiperprolactinemia/sangue , Prolactina/sangue , Animais , Elefantes , Ciclo Estral/metabolismo , Ciclo Estral/fisiologia , Feminino , Hipófise/metabolismo
8.
Contemp Clin Trials Commun ; 34: 101171, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37448911

RESUMO

Background: Latina mothers' stress is associated with their children's health behaviors and risk for obesity; however, existing pediatric health promotion programs have not focused on maternal stress reduction. Methods: Herein we describe a study design that will examine the acceptability and feasibility of Calma, Conversa, y Cría (CCC) a 6-week mindful parenting intervention designed to reduce stress. We present the results of qualitative research with Latina mothers and experts in Latinx health and mindfulness who provided culturally-relevant feedback on existing mindful parenting strategies to inform the development of CCC. Fifty Latina mothers of children ages 3-11 years will be randomly assigned to CCC or an enhanced usual care health education intervention. Acceptability will be assessed through participant satisfaction surveys and exit interviews. Feasibility will be determined through detailed tracking of recruitment, retention, and attendance rates. A signal regarding any group differences in maternal stress, health-related parenting practices, child diet, child physical activity, and child quality of life will be explored. Discussion: The development of interventions that can reduce maternal stress and risk for obesity in Latinx children is critical to significantly reduce negative health impacts in this underserved population. Our approach includes the identification of effective cultural adaptations that should improve the feasibility and acceptability of mindful parenting strategies in Latinx families, ideally reducing maternal stress and improving parenting behaviors related to child health. If successful, CCC will be examined in a larger efficacy trial involving the measurement of objective biomarkers of children's chronic disease risk.

9.
Biostatistics ; 11(3): 432-52, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20156988

RESUMO

Frequently, exposure data are measured over time on a grid of discrete values that collectively define a functional observation. In many applications, researchers are interested in using these measurements as covariates to predict a scalar response in a regression setting, with interest focusing on the most biologically relevant time window of exposure. One example is in panel studies of the health effects of particulate matter (PM), where particle levels are measured over time. In such studies, there are many more values of the functional data than observations in the data set so that regularization of the corresponding functional regression coefficient is necessary for estimation. Additional issues in this setting are the possibility of exposure measurement error and the need to incorporate additional potential confounders, such as meteorological or co-pollutant measures, that themselves may have effects that vary over time. To accommodate all these features, we develop wavelet-based linear mixed distributed lag models that incorporate repeated measures of functional data as covariates into a linear mixed model. A Bayesian approach to model fitting uses wavelet shrinkage to regularize functional coefficients. We show that, as long as the exposure error induces fine-scale variability in the functional exposure profile and the distributed lag function representing the exposure effect varies smoothly in time, the model corrects for the exposure measurement error without further adjustment. Both these conditions are likely to hold in the environmental applications we consider. We examine properties of the method using simulations and apply the method to data from a study examining the association between PM, measured as hourly averages for 1-7 days, and markers of acute systemic inflammation. We use the method to fully control for the effects of confounding by other time-varying predictors, such as temperature and co-pollutants.


Assuntos
Poluição do Ar , Teorema de Bayes , Modelos Lineares , Modelos Biológicos , Material Particulado/efeitos adversos , Humanos , Contagem de Leucócitos
10.
Epidemiology ; 22(4): 599-606, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21543985

RESUMO

BACKGROUND: Left truncation occurs when subjects who otherwise meet entry criteria do not remain observable for a later start of follow-up. We investigated left truncation in occupational studies due to inclusion of workers hired before the start of follow-up in a simulation study. METHODS: Using Monte Carlo methods, we simulated null and positive associations between exposure (work duration) and mortality for 500 datasets of 5000 subjects, assuming the absence and presence of heterogeneity in susceptibility to disease and to the effect of exposure. We examined incident hires (followed since hire) and left-truncated prevalent hires (those hired before baseline and remained employed at baseline). We estimated the association (&OV0404;1*) as the mean slope using Cox proportional hazards with a linear term for exposure, under scenarios with and without susceptibility. RESULTS: With homogeneous susceptibility, there were no differences between incident and prevalent hires. Introducing only disease susceptibility did not change results. However, with heterogeneous susceptibility to the effect of exposure, downward bias was observed among prevalent hires under both the true null and positive exposure-response scenarios. The bias increased with time between hire and baseline (null: &OV0404;1* = 0.05 [SD = 0.08], &OV0404;1* = -0.08 [SD = 0.24], &OV0404;1* = -0.18 [SD = 0.98] if hired <15, 15 to <30, and ≥ 30 years before baseline, respectively), coincident with a decreasing percentage of susceptible subjects. CONCLUSIONS: Prevalent hires induce downward bias in an occupational cohort. This occurs because subjects who are less susceptible to the exposure remain exposed the longest, thereby underestimating the association.


Assuntos
Viés , Estudos de Coortes , Projetos de Pesquisa Epidemiológica , Doenças Profissionais/mortalidade , Exposição Ocupacional/estatística & dados numéricos , Seguimentos , Humanos , Método de Monte Carlo , Modelos de Riscos Proporcionais
11.
Stat Comput ; 31(2)2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36324372

RESUMO

Historical Functional Linear Models (HFLM) quantify associations between a functional predictor and functional outcome where the predictor is an exposure variable that occurs before, or at least concurrently with, the outcome. Prior work on the HFLM has largely focused on estimation of a surface that represents a time-varying association between the functional outcome and the functional exposure. This existing work has employed frequentist and spline-based estimation methods, with little attention paid to formal inference or adjustment for multiple testing and no approaches that implement wavelet-bases. In this work, we propose a new functional regression model that estimates the time-varying, lagged association between a functional outcome and a functional exposure. Building off of recently developed function-on-function regression methods, the model employs a novel use the wavelet-packet decomposition of the exposure and outcome functions that allows us to strictly enforce the temporal ordering of exposure and outcome, which is not possible with existing wavelet-based functional models. Using a fully Bayesian approach, we conduct formal inference on the time-varying lagged association, while adjusting for multiple testing. We investigate the operating characteristics of our wavelet-packet HFLM and compare them to those of two existing estimation procedures in simulation. We also assess several inference techniques and use the model to analyze data on the impact of lagged exposure to particulate matter finer than 2.5µg, or PM2.5, on heart rate variability in a cohort of journeyman boilermakers during the morning of a typical day's shift.

12.
Behav Ther ; 52(6): 1543-1557, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34656205

RESUMO

OBJECTIVE: This study is the first controlled trial of comprehensive behavioral (ComB) treatment of trichotillomania (TTM). ComB provides individualized treatment based on factors triggering and maintaining hair pulling. METHOD: Participants (N = 36) were adults (M = 34.08 years old, SD = 12.26) meeting DSM5 criteria for TTM. A majority were female (80%) and Caucasian (75%), whereas 17% were African American and 19% Hispanic/Latinx. In a parallel-group design, participants were randomly assigned to (a) Immediate ComB (12 sessions) or (b) Minimal Attention Control (MAC), followed by delayed ComB after week 12. Follow-up continued through week 38. Primary outcomes were self-report (Massachusetts General Hospital Hair pulling Scale; MGH-HPS) and interviewer-rated (NIMH-Trichotillomania Impact Scale and Trichotillomania Severity Scale; TIS/TSS) TTM symptom severity, as well as diagnosis (Trichotillomania Diagnostic Interview). RESULTS: Immediate efficacy of ComB (vs. MAC) was statistically significant (p = .03) for self-reported symptoms, with an effect size d = -.78, but not significant for interviewer-rated symptoms or diagnostic status. Immediate ComB was significantly more likely than MAC (27% vs. 0%) to lead to complete abstinence from hair pulling at week 12. Follow-ups showed good maintenance of effects. CONCLUSIONS: Efficacy of ComB was established for self-reported symptoms. Future research is needed to establish whether the lack of more widespread effects stems from limitations of the model or to a need for more extensive therapist training, as secondary analyses suggested stronger results among therapists with more TTM experience.


Assuntos
Tricotilomania , Adulto , Negro ou Afro-Americano , Terapia Comportamental , Feminino , Humanos , Masculino , Autorrelato , Tricotilomania/diagnóstico , Tricotilomania/terapia
13.
J Consult Clin Psychol ; 88(10): 965-970, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33048572

RESUMO

OBJECTIVE: Smoking reexposure after a quit attempt (i.e., lapse) increases relapse risk, but lapse recovery is possible. Using a 6-day analogue model of smoking cessation and lapse, this study tested the effect of a single lapse cigarette on the risk of subsequent smoking. Abstinence self-efficacy (ASE) and depressive symptoms (using the Center for Epidemiological Studies Depression Scale, CES-D) were also examined as hypothesized moderators of lapse recovery. METHOD: After receiving cessation counseling and achieving 2 days of incentivized abstinence, 54 daily smokers (mean age: 41 years, 61% African American, 63% male) were randomly assigned to smoke 1 cigarette or to a no-lapse control condition. Participants were then offered monetary incentives to abstain for 3 more days and smoking was monitored. RESULTS: Compared to the control condition, participants who experienced a lapse had a 2.5 times greater risk of smoking in the first 24 hours Furthermore, a lapse resulted in much greater risk of subsequent smoking compared to the control condition among individuals with lower postquit ASE scores (p = .044) and greater CES-D scores (p = .040). CONCLUSIONS: These findings provide preliminary evidence that a single lapse cigarette after quitting plays a causal role in subsequent smoking and suggest that individuals with lower postquit ASE and greater depressive symptoms are less likely to recover from a lapse. Future research should investigate factors associated with lapse recovery and failure so that effective lapse-responsive strategies can be developed. Laboratory models provide an efficient and controlled method to examine such processes. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Assuntos
Depressão/psicologia , Autoeficácia , Fumantes/psicologia , Abandono do Hábito de Fumar/psicologia , Fumar/psicologia , Adulto , Aconselhamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Motivação , Recidiva , Abandono do Hábito de Fumar/métodos , Resultado do Tratamento , Adulto Jovem
14.
Addict Behav ; 102: 106140, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31706142

RESUMO

In a motivational interviewing (MI) framework of decision-making, we consider potential outcomes for both a primary choice and an alternative choice (DiClemente & Velazquez, 2002). Thus, we would expect that motivation to quit smoking is related to expectancies for quitting smoking and expectancies for continuing to smoke. While smoking expectancies have been frequently studied, less attention has been paid to abstinence expectancies. The present study sought to clarify the predictive utility of smoking and abstinence expectancies together for smoking motivation and behavior, versus measuring smoking expectancies alone. Expectancies were measured at baseline; outcomes were measured at baseline and one-month follow-up. Smoking expectancies were assessed via the Smoking Consequences Questionnaire-Adult (Copeland, Brandon, & Quinn, 1995), and abstinence expectancies were assessed via the Perceived Risks and Benefits of Quitting scale (McKee, O'Malley, Salovey, Krishnan-Sarin, & Mazure, 2005). Outcomes included motivation to quit (Contemplation Ladder, Biener & Abrams, 1991; Stage of Change, DiClemente et al., 1991), and average daily smoking rate. Data was analyzed for 183 smokers at baseline and 166 at follow-up. Baseline smoking expectancies and abstinence expectancies were each uniquely associated with concurrent motivation to quit, but not concurrent smoking rate. Abstinence expectancies uniquely predicted changes in smoking rate over time. Smoking and abstinence outcome expectancies may relate differently to smoking behavior, motivation to quit, and changes in these constructs over time.


Assuntos
Comportamento de Escolha , Tomada de Decisões , Motivação , Fumantes/psicologia , Abandono do Hábito de Fumar/psicologia , Fumar/psicologia , Adulto , Idoso , District of Columbia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Entrevista Motivacional , Valor Preditivo dos Testes , Teoria Psicológica , Autorrelato , Fumantes/estatística & dados numéricos , Abandono do Hábito de Fumar/estatística & dados numéricos
15.
J Occup Environ Med ; 62(10): 810-815, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32568818

RESUMO

OBJECTIVE: Assessment of possible relationships between work-related psychosocial measures and self-reported low back pain (LBP) outcomes in a large pooled dataset of 1929 participants from 82 facilities in the United States. METHODS: Pooled data from three prospective cohort studies were used to calculate odds ratios (OR) and 95% confidence intervals (95% CI) for relationships between psychosocial factors and the LBP outcomes. Personal and occupational confounders were controlled for in adjusted Logistic regression models. RESULTS: Supervisor support and job satisfaction were significantly (P < 0.05) related to all three LBP outcomes. Other psychosocial factors were significantly (P < 0.05) associated with at least one of the LBP outcomes. Adjusted ORs ranged from approximately 1.50 to 3.50 for most associations. CONCLUSIONS: There is a significant relationship between work-related psychosocial measures and LBP outcomes.


Assuntos
Dor Lombar , Doenças Profissionais , Humanos , Incidência , Dor Lombar/psicologia , Doenças Profissionais/psicologia , Medição da Dor , Estudos Prospectivos , Fatores de Risco , Inquéritos e Questionários , Estados Unidos
16.
Comput Stat Data Anal ; 53(7): 2605-2616, 2009 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-20161167

RESUMO

This article presents an application and a simulation study of model fit criteria for selecting the optimal degree of smoothness for penalized splines in Cox models. The criteria considered were the Akaike information criterion, the corrected AIC, two formulations of the Bayesian information criterion, and a generalized cross-validation method. The estimated curves selected by the five methods were compared to each other in a study of rectal cancer mortality in autoworkers. In the stimulation study, we estimated the fit of the penalized spline models in six exposure-response scenarios, using the five model fit criteria. The methods were compared based on a mean squared-error score and the power and size of hypothesis tests for any effect and for detecting nonlinearity. All comparisons were made across a range in the total sample size and number of cases.

17.
Occup Environ Med ; 64(4): 244-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16912088

RESUMO

BACKGROUND: Rectal cancer has been previously associated with exposure to metalworking fluids in a cohort mortality study of autoworkers. OBJECTIVE: To better specify the exposure-response relationship with straight metalworking fluids (mineral oils) by applying non-parametric regression methods that avoid linearity constraints and arbitrary exposure cut points and by lagging exposure to account for cancer latency, in a nested case-control analysis. METHODS: In addition to the classical Poisson regression with categorical exposure, survival models with penalised splines were used to estimate the exposure-response relationship between cumulative exposure to straight metalworking fluid and mortality from rectal cancer. Exposures to water-based metalworking fluids were treated as potential confounders, and all exposures were lagged by 5, 10, 15 and 20 years to account for cancer latency. The influence of the highest exposures was dealt with by a log transformation and outlier removal. The sensitivity of the penalised splines to alternative criteria for model selection and to the placement of knots was also examined. RESULTS: The hazard ratio for mortality from rectal cancer increased essentially linearly with cumulative exposure to straight metalworking fluid (with narrow confidence bands) up to a maximum of 2.2 at the 99th centile of exposure and then decreased (with wide confidence bands). Lagging exposure up to 15 years increased the initial steepness of the curve and raised the maximum hazard ratio to 3.2. CONCLUSIONS: Non-parametric smoothing of lagged exposures has shown stronger evidence for a causal association between straight metalworking fluid and rectal cancer than was previously described using standard analytical methods. This analysis suggests an exposure-response trend that is close to linear and statistically significant over most of the exposure range and that increases further with lagged exposures. Smoothing should be regularly applied to environmental studies with quantitative exposure estimates to refine characterisation of the dose-response relationship.


Assuntos
Automóveis , Óleos Industriais/toxicidade , Doenças Profissionais/induzido quimicamente , Exposição Ocupacional/efeitos adversos , Neoplasias Retais/induzido quimicamente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Masculino , Metalurgia , Michigan/epidemiologia , Pessoa de Meia-Idade , Análise de Regressão
18.
Occup Environ Med ; 64(10): 681-7, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17449560

RESUMO

OBJECTIVE: To explore the healthy worker survivor effect (HWSE) in a study of Vermont granite workers by distinguishing "prevalent" from "incident" hires based on date of hire before or after the start of follow-up. METHODS: Records of workers between 1950 and 1982 were obtained from a medical surveillance programme. Proportional hazards models were used to model the association between silica exposure and lung cancer mortality, with penalised splines used to smooth the exposure-response relationship. A sensitivity analysis compared results between the original cohort and subcohorts defined by restricting date of hire to include varying proportions of prevalent hires. RESULTS: Restricting to incident hires reduced the 213 cases by 74% and decreased the exposure range. The maximum mortality rate ratio (MRR) was close to twofold in all subcohorts. However, the exposure at which the maximum MRR was achieved decreased from 4.0 to 0.6 mg-year/m3 as the proportion of prevalent hires decreased from 50% in the original cohort to 0% in the subcohort of incident hires. CONCLUSION: Despite loss in power and restricted exposure range, decreasing the relative proportion of prevalent to incident hires reduced HWSE bias, resulting in stronger evidence for a dose-response between silica exposure and lung cancer mortality.


Assuntos
Emprego/estatística & dados numéricos , Indústrias/estatística & dados numéricos , Neoplasias Pulmonares/mortalidade , Dióxido de Silício , Silicose/mortalidade , Idoso , Viés , Estudos de Coortes , Seguimentos , Efeito do Trabalhador Sadio , Humanos , Incidência , Pessoa de Meia-Idade , Prevalência , Modelos de Riscos Proporcionais , Análise de Sobrevida , Fatores de Tempo , Vermont/epidemiologia
19.
Comput Math Methods Med ; 2017: 7518035, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29312462

RESUMO

Truncated power basis expansions and penalized spline methods are demonstrated for estimating nonlinear exposure-response relationships in the Cox proportional hazards model. R code is provided for fitting models to get point and interval estimates. The method is illustrated using a simulated data set under a known exposure-response relationship and in a data application examining risk of carpal tunnel syndrome in an occupational cohort.


Assuntos
Síndrome do Túnel Carpal/fisiopatologia , Simulação por Computador , Doenças Profissionais/etiologia , Modelos de Riscos Proporcionais , Estresse Mecânico , Extremidade Superior/lesões , Adulto , Estudos de Coortes , Interpretação Estatística de Dados , Humanos , Medição de Risco , Software
20.
Behav Brain Res ; 335: 174-184, 2017 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-28797598

RESUMO

Alcohol exposure in adolescence is a contributing factor toward reward-seeking behavior in adulthood. This reward-seeking behavior is assessed in animal models using the conditioned place preference (CPP) paradigm. In this study, ethanol-induced change in time spent by zebrafish on the initially non-preferred tank side was studied by conditioning adult zebrafish to ethanol dissolved in water (0.00% 1.00%; 1.25%; 1.50%; 1.60%; 1.75% vol/vol) paired with an initially non-preferred environment. Following a single conditioning cycle, fish swam unrestricted in the CPP chamber to assess changes in preference. Daily 20-min pre-exposure to ethanol for 1 week during the juvenile stage starting at either 20days post fertilization (dpf) or 40 dpf altered percent time spent on the ethanol-paired side in adulthood in a dose-dependent and sex-dependent manner. The results suggest that male and female zebrafish are an effective model in which to investigate behavioral correlates of ethanol-induced changes in neural circuits implicated in reward and anxiety.


Assuntos
Comportamento Animal/efeitos dos fármacos , Etanol/farmacologia , Animais , Condicionamento Clássico/efeitos dos fármacos , Condicionamento Psicológico/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Masculino , Recompensa , Fatores Sexuais , Peixe-Zebra
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