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At least 1,351 records · Page 75Linked to original sources
PubMed2005

The impact of an organ donation registration information program for high school students in the Netherlands.

In 1998, a new organ donor registration system was implemented in the Netherlands to increase the number of potential donors. A high school education program was developed to prepare adolescents to make an informed decision about organ donation. A post-test only randomised controlled trial was conducted in 39 high schools including 2868 students. Students within schools were randomly allocated to either attend the organ donation education program or not. The impact of the program on students' intention to register their organ donation preference (and determinants thereof) were analysed using multivariate multileveling modelling (MlwiN). The results show that students who were exposed to the education program had more favourable registration intentions (B = .40), were more often willing to be donors (OR = 1.45), and had greater knowledge about (B = 3.84) and more positive social outcome expectations (B = .09) and self-efficacy regarding organ donation registration (B=.22). Lastly, they experienced significantly less negative outcome expectations related to organ donation registration (B = -.15). Students' evaluation of the school-based education program was favourable. The present organ donation registration program proved to be effective in changing determinants of organ donation registration, and a large-scale implementation in the Dutch high school curriculum is planned.

Adolescent↗
PubMed2001

Investigating neighborhood and area effects on health.

The past few years have witnessed an explosion of interest in neighborhood or area effects on health. Several types of empiric studies have been used to examine possible area or neighborhood effects, including ecologic studies relating area characteristics to morbidity and mortality rates, contextual and multilevel analyses relating area socioeconomic context to health outcomes, and studies comparing small numbers of well-defined neighborhoods. Strengthening inferences regarding the presence and magnitude of neighborhood effects will require addressing a series of conceptual and methodological issues. Many of these issues relate to the need to develop theory and specific hypotheses on the processes through which neighborhood and individual factors may jointly influence specific health outcomes. Important challenges include defining neighborhoods or relevant geographic areas, identifying significant area or neighborhood characteristics, specifying the role of individual-level variables, incorporating life-course and longitudinal dimensions, combining a variety of research designs, and avoiding reductionism in the way in which "neighborhood" factors are incorporated into models of disease causation and quantitative analyses.analyses.

Epidemiologic Methods↗
PubMed2006

Project Towards No Drug Abuse: long-term substance use outcomes evaluation.

OBJECTIVES: This paper presents up to 5 years post-program outcomes of Project Towards No Drug Abuse (Project TND), a drug abuse prevention program conducted in South California alternative high school system during years 1994-1999. METHODS: The effects of a 9-session health motivation--social skills--decision-making curriculum were evaluated. Twenty-one schools recruited were randomly assigned to standard care (control), classroom only, or a classroom plus semester-long school-as-community component. Last 30-day use of cigarettes, alcohol, marijuana, and hard drugs were assessed at three time intervals: short-term (year 1), middle-term (years 2 or 3), and long-term (years 4 or 5). Multilevel random coefficients modeling were employed to estimate the adjusted levels of substance use. RESULTS: Among 1578 baseline subjects, follow-up data were available for 68% (year 1), 66% (years 2 or 3), and 46% (years 4 or 5) of subjects, respectively. Results revealed significant positive long-term program effects for hard drug use at year 4 or 5 for the two program interventions (P = 0.02). CONCLUSIONS: Project TND reduced hard drug use in the 46% who were successfully followed. It is the first program to demonstrate long-term self-reported behavioral effects on hard drug use among high-risk youth by using a school-based, limited-session model.

Adolescent↗
PubMed2002

Are cognitive impairments associated with sensitivity to stress in schizophrenia? An experience sampling study.

OBJECTIVE: Patients with a diagnosis of schizophrenia display cognitive impairments and abnormal sensitivity to stress. However, little is known about the relationship between these two endophenotypes. METHOD: Neuropsychological tests were administered to 42 patients with schizophrenia or other psychosis to assess cognitive functioning, and the experience sampling method (a structured diary technique assessing current context and mood in daily life) was used to assess 1) appraised subjective stress related to daily events and activities and 2) emotional reaction to these daily life stressors. RESULTS: Multilevel random regression analyses showed that in some instances, cognitive functioning did not alter emotional reaction to stress. In other instances, an inverse relationship was found, indicating that a better performance on neuropsychological tests was related to greater emotional reaction to stress. CONCLUSIONS: The results indicate that emotional reaction to stress in the daily lives of patients with schizophrenia may not be a consequence of cognitive impairments and that the two mechanisms may act through different pathways. Such pathways may be related to the extremes of clinical outcome that have been observed in schizophrenia: an episodic, reactive, good outcome and a more chronic form characterized by high levels of negative symptoms and cognitive impairments.

Adult↗
PubMed2006

Methodological aspects in the assessment of treatment effects in observational health outcomes studies.

Prospective observational studies, which provide information on the effectiveness of interventions in natural settings, may complement results from randomised clinical trials in the evaluation of health technologies. However, observational studies are subject to a number of potential methodological weaknesses, mainly selection and observer bias. This paper reviews and applies various methods to control for selection bias in the estimation of treatment effects and proposes novel ways to assess the presence of observer bias. We also address the issues of estimation and inference in a multilevel setting. We describe and compare the use of regression methods, propensity score matching, fixed-effects models incorporating investigator characteristics, and a multilevel, hierarchical model using Bayesian estimation techniques in the control of selection bias. We also propose to assess the existence of observer bias in observational studies by comparing patient- and investigator-reported outcomes. To illustrate these methods, we have used data from the SOHO (Schizophrenia Outpatient Health Outcomes) study, a large, prospective, observational study of health outcomes associated with the treatment of schizophrenia. The methods used to adjust for differences between treatment groups that could cause selection bias yielded comparable results, reinforcing the validity of the findings. Also, the assessment of observer bias did not show that it existed in the SOHO study. Observational studies, when properly conducted and when using adequate statistical methods, can provide valid information on the evaluation of health technologies.

Bayes Theorem↗
PubMed2004

Children of mothers diagnosed with serious mental illness: patterns and predictors of service use.

Children who have a parent diagnosed with a mental illness are at risk of psychiatric and behavioral problems; yet, these children do not necessarily receive needed services. Research has investigated correlates of child mental health service use, but not for these high-risk children. This study is part of an NIMH-funded, longitudinal investigation and describes child problems, service use, and predictors of service use for 506 children of 252 mothers diagnosed with serious mental illness. Mothers are primarily poor, minority women from urban areas. A multilevel-model approach is used to examine service use for multiple siblings in a family. More than one third of children had received services (from school or mental health agencies) in their lifetimes. Service use was predicted by child demographic characteristics (being male, non-African American, and older), social context variables (more negative life events, less financial satisfaction, and more parenting dissatisfaction), and maternal psychiatric variables (positively by high levels of case management receipt and affective diagnoses, negatively by maternal substance abuse history). In a subsample of "target children," mothers' rating of child behavior problems additionally predicted service use. Implications of results for research and intervention are discussed.

Adolescent↗
PubMed1999

Effects of hostility on ambulatory blood pressure and mood during daily living in healthy adults.

This study (a) tested the effects of hostile attributes on ambulatory blood pressure (BP), heart rate, and mood monitored repeatedly over 3 days in 100 healthy men and women and (b) determined whether the cardiovascular effects of trait hostility were moderated by mood. Multilevel random-coefficients regression analyses showed that hostile individuals exhibited higher systolic and diastolic BP and rated their current moods as more negative and less positive throughout the monitoring. Individuals low in hostility exhibited high BP only during the few occasions when they experienced negative mood. However, these patterns were true only when participants were classified by Potential for Hostility ratings from the Structured Interview (R. H. Rosenman, 1978), not by the Cynical Hostile Attitudes score derived from the Cook-Medley scale. Results provide convergent and ecological validity of interview rating of hostility and illuminate one possible dynamic mechanism by which overt hostile behaviors might contribute to the rates of increased cardiovascular morbidity and mortality.

Activities of Daily Living↗
PubMed1990

Nonlinear system identification for cascaded block model: an application to electrode polarization impedance.

A new algorithm has been developed to identify a system divided into cascaded blocks of dynamic linear (L), static nonlinear (N), and dynamic linear (L) subsystems based strictly on the input-output relationship. The nonlinear element is assumed to be equicontinuous, or must be satisfied by the Weierstrass criterion. Therefore, it could either be continuous type as represented by polynomial approximation or abrupt type as represented by piecewise-linear segments. The process uses a series of multilevel input to decouple the two linear subsystems from the nonlinear subsystem and then applies the predictor-corrector algorithm to minimize a cost function to obtain the parameter of the subsystem. The method does not restrict the type of input signal and no prior knowledge of the subsystems is necessary. Numerical example for a prescribed system is given and the results show almost identical values by any one of the three types of input, namely: step, sinusoidal, or white noise. Three computer programs have been developed for the identification of the system with odd, even, and piecewise abrupt types of nonlinearity. The method is applied to model the interfacial phenomenon of noble metal electrode (Pt) at the nonlinear range and the algorithm is verified by comparison with the result developed previously.

Algorithms↗
PubMed1991

Multilevel model to assess appropriateness of pediatric serum drug concentrations.

A multilevel model reviewing four assessment levels for pediatric serum drug concentrations was developed. Criteria for appropriate indication, sample collection, documentation, and utilization were based on therapeutic drug monitoring principles. The model was applied to 222 pediatric serum drug concentrations. Inadequate documentation was a major problem, but it occurred at a lower rate (37%) than previously reported. The rates of inappropriateness for indication (15%), sample collection (16%), and utilization (10%) were well within reported ranges but were significantly lower with pharmacy input. Overall, 48.2% of drug concentrations were inappropriate. Digoxin, phenobarbital, and aminoglycosides had the highest error rates. The annualized cost of inappropriate serum drug concentrations was $12,325. The described method allows for targeting of educational programs with defined areas for improvement. The findings of this study also support the involvement of clinical pharmacists in the therapeutic drug monitoring process.

Costs and Cost Analysis↗
PubMed1977

A systems approach to the child, school, family, and community in an urban area.

Fifteen eighth-grade students, their parents, teachers, and relevant school administrators received a multilevel systems consultation from a community mental health center. Clients were conceptualized and worked with in terms of the subsystem to which they belonged and with regard to the interrelationships of the other subsystems comprising the school-community system. Theoretical considerations following Lewin's life-space concept are described as a basis for this approach in contrast to more traditional ones which typically fail to treat directly, simultaneously, and/or sequentially all client subsystems, e.g., child, school, family, and community. The consultation is described as a case example with each client contributing to the evaluation of the intervention. Although the consultation could not be carried out entirely along the lines originally conceived, it serves as a helpful model for making a more potent impact in school interventions.

Child Behavior Disorders↗
PubMed2004

Daily processes in stress and smoking: effects of negative events, nicotine dependence, and gender.

The author used a multilevel daily process design to examine relations among daily negative events, perceived stress, smoking, and smoking urges. The moderating effects of gender and nicotine dependence were also explored. Fifty-one adult community-residing smokers recorded negative events, perceived stress, cigarette smoking, and urges to smoke 4 times daily for 14 days. Analyses of within-person relations showed that participants smoked more cigarettes and experienced more urges to smoke on occasions with higher numbers of negative events and higher levels of perceived stress. These relations were stronger for men than for women. Nicotine dependence did not interact with events or stress in predicting smoking or urges. These findings build on laboratory studies and cross-sectional surveys by showing that in naturalistic settings, occasions with negative events and perceived stress are associated with smoking and urges to smoke.

Adult↗
PubMed2003

Neural correlates of "hot" and "cold" emotional processing: a multilevel approach to the functional anatomy of emotion.

The neural correlates of two hypothesized emotional processing modes, i.e., schematic and propositional modes, were investigated with positron emission tomography. Nineteen subjects performed an emotional mental imagery task while mentally repeating sentences linked to the meaning of the imagery script. In the schematic conditions, participants repeated metaphoric sentences, whereas in the propositional conditions, the sentences were explicit questions about specific emotional appraisals of the imagery scenario. Five types of emotional scripts were proposed to the subjects (happiness, anger, affection, sadness, and a neutral scenario). The results supported the hypothesized distinction between schematic and propositional emotional processing modes. Specifically, schematic mode was associated with increased activity in the ventromedial prefrontal cortex whereas propositional mode was associated with activation of the anterolateral prefrontal cortex. In addition, interaction analyses showed that schematic versus propositional processing of happiness (compared with the neutral scenario) was associated with increased activity in the ventral striatum whereas "schematic anger" was tentatively associated with activation of the ventral pallidum.

Adult↗
PubMed2000

The impact of area deprivation on differences in health: does the choice of the geographical classification matter?

OBJECTIVE: Many studies show the average health status in deprived areas to be poorer and the use of health care to be higher, but there is hardly any information on the impact of the geographical classification on the size of these differences. This study examines the impact of the geographical classification on the clustering of poor health per area and on the size of the differences in health by area deprivation. DESIGN: Data on self reported health regarding 5121 people were analysed using three classifications: neighbourhoods, postcode sectors and boroughs. Multilevel logistic models were used to determine the clustering of poor health per area and the size of the differences in health by area deprivation, without and subsequently with adjustment for individual socioeconomic status. SETTING: General population aged 16 years and over of Amsterdam, The Netherlands. MAIN OUTCOME MEASURES: Self rated health, mental symptoms (General Health Questionnaire, 12-item version), physical symptoms and long term functional limitations. MAIN RESULTS: The clustering of poor health is largest in neighbourhoods and smallest in postcode sectors. Health differences by area deprivation differ only slightly for the three geographical classifications, both with and without adjustment for individual socioeconomic status. CONCLUSIONS: In this study, the choice of the geographical classification affects the degree of clustering of poor health by area but it has hardly any impact on the size of health differences by area deprivation.

Adolescent↗
PubMed2005

Low linking social capital as a predictor of coronary heart disease in Sweden: a cohort study of 2.8 million people.

This study investigated the association between the recently minted concept of linking social capital and incidence of coronary heart disease (CHD). A follow-up study of 1,358,932 men and 1,446,747 women in Sweden aged 45-74 years was conducted between 1 January 1998 and 31 December 1999. Neighbourhood linking social capital was conceptualised as proportions of individuals voting in local government elections at neighbourhood level. The neighbourhood- and individual-level factors were analysed within a multilevel framework. Linking social capital was associated with CHD in both men and women beyond individual-level factors: in neighbourhoods with low linking social capital the odds ratios were 1.19 (CI = 1.14-1.24) and 1.29 (CI = 1.21-1.38) for men and women, respectively, after adjustment for age, country of birth, education, marital status, and housing tenure. The significant between-neighbourhood variance (i.e. the random intercept) showed significant differences in CHD incidence between neighbourhoods. Even in a relatively egalitarian society, as exemplified by the Swedish Welfare State, individual health is affected by differences between neighbourhoods in linking social capital. The use of linking social capital represents a novel conceptual advance in research on the association between CHD, one of the major causes of death in Western countries, and the multidimensional aspects of social capital.

Aged↗
PubMed1998

Posterolateral fusion for isthmic spondylolisthesis in adults: analysis of fusion rate and clinical results.

This is a retrospective study of 83 consecutive adult patients with isthmic spondylolisthesis who underwent identical decompressive surgery combined with posterolateral spine fusion. We sought to determine factors that affect the fusion rate and clinical outcomes for adult patients with isthmic spondylolisthesis. The outcome of operative treatment for isthmic spondylolisthesis in adults has been poorly documented, as opposed to the treatment of children and adolescents. From 1989 to 1994, 83 consecutive adult patients (age 19-66 years; average, 38 years) underwent surgical treatment consisting of the Gill procedure and posterolateral fusion for isthmic lumbosacral spondylolisthesis. Seventy-three patients (46 men and 27 women) were available for an average of 3.8 years' follow-up (1.0-7.4 years). Thirty-eight underwent one-level fusion, and 35 underwent two-level fusions. Pedicle screw instrumentation was performed in 69 patients. A postoperative questionnaire including the Roland index, clinical charts, and radiographs were reviewed by an independent observer to assess the postoperative course, clinical results, and fusion status. Twenty-five variables were evaluated to determine which affected the fusion and success rates. Primary radiologic fusion and clinical success rates were 78 and 71%, respectively. There was a strong positive correlation between radiologic fusion and clinical success. Overall, single-level fusions showed an 82% fusion rate, and two-level fusions, a 74% rate. For two-level fusions, a significantly higher fusion rate was achieved with a rigid pedicle screw-fixation system than a semirigid system (79 vs. 57%). For smokers, cessation from smoking postoperatively did not increase the fusion rate, and patients who continued to smoke after surgery showed a significantly higher rate of pseudarthrosis. Worker's compensation status did not affect clinical results significantly. Patients who continued to take nonsteroidal antiinflammatory drugs (NSAIDs) >3 months postoperatively showed significantly lower fusion and success rates (44 and 37%). Single-level lumbar fusion for isthmic spondylolisthesis was equally effective with either rigid or semirigid pedicle screw instrumentation. For multilevel spine fusion in isthmic spondylolisthesis, rigid pedicle screw-fixation systems resulted in a high fusion rate. A smoking history or NSAIDs use postoperatively had strong negative influences on the fusion and clinical success rates.

Adult↗
PubMed2002

Access to specialist cancer care: is it equitable?

The first principle of the Calman-Hine report's recommendations on cancer services was that all patients should have access to a uniformly high quality of care wherever they may live. This study aimed to assess whether the uptake of chemotherapy for colorectal cancer varied by hospital type in Scotland. Hospitals were classified according to cancer specialisation rather than volume of patients. To indicate cancer specialisation, hospitals were classified as 'cancer centres', 'cancer units' and 'non-cancer' hospitals. Colorectal cancer cases were obtained from cancer registrations linked to hospital discharge data for the period January 1992 to December 1996. Multilevel logistic regression was used to model the binary outcome, namely whether or not a patient received chemotherapy within 6 months of first admission to any hospital. The results showed that patients admitted first to a 'non-cancer' hospital were less than half as likely to go on to receive chemotherapy as those first admitted to a cancer unit or centre (OR=0.28). This result was not explained by distance between hospital of first admission and nearest cancer centre, nor by increasing age or severity of illness. The study covers the period immediately preceding the introduction of the Calman-Hine report in Scotland and should serve as a baseline for future monitoring of access to specialist care.

Adolescent↗
PubMed2000

Impact of HIV-positive speakers in a multicomponent, school-based HIV/STD prevention program for inner-city adolescents.

Qualitative and quantitative data from Safer Choices, a school-based multicomponent HIV prevention program, were examined to determine the impact of HIV-positive speakers on inner-city adolescents' HIV risk perception and empathy for people with HIV or AIDS. Inductive analyses were used to assess student reactions to speakers. Multilevel regression modeling techniques were used to analyze student survey data (n = 1,491) to determine the effect of speakers alone, as well as in combination with the multicomponent intervention, and a knowledge-based curriculum (comparison condition). Results showed that speakers were highly popular with students and teachers, and had a positive short-term impact on students' attitudes. Although not statistically significant, the combination of intervention and speakers had the greatest impact on outcome variables. Integrating HIV-positive speakers into multicomponent programs may have a positive impact on inner-city youth. Utilizing speakers without other educational components may have minimal effects. Strategies for training and utilizing HIV-positive speakers in school settings are included.

Adolescent↗
PubMed2000

Small area variations in health related behaviours; do these depend on the behaviour itself, its measurement, or on personal characteristics?

In this paper we examine the patterning, by small areas, of four health related behaviours (smoking, alcohol consumption, diet, and exercise) in the West of Scotland, after controlling for a range of individual/household characteristics, using multilevel models. Smoking and drinking were measured both as binary and as continuous variables, and diet and exercise were each measured in two ways: 'good' (health promoting) and 'bad' (health damaging). 'Area effects' (unattributed variation by post code sector) were found for 'bad' diet only. 'Good' and 'bad' diet, 'bad' exercise patterns and current smoking were associated with postcode sector deprivation. For 'bad' diet this effect was found only for individuals in more affluent households, and for 'good' exercise and current smoking the association with area deprivation differed between adolescents and adults. We conclude that the influence of area on health related behaviours varies according to the behaviour and the way it is measured, and that the influence of area deprivation and/or of area can vary by age and household deprivation.

Adolescent↗