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PubMed1985

Self-esteem, ethnic identity, and behavioral adjustment among Anglo and Chicano adolescents in West Texas.

This study provides a comparison of similarities and differences with respect to ethnic identity between Anglo and Chicano adolescents from Texas. A path analysis model was used to test a theoretical assumption concerning proposed antecedents and consequences of self-esteem. Research instruments included the Rosenberg Self Esteem Scale, the Semantic Differential (scales for Myself and My Ethnic Group) and the McGuire White Measure of Social Status. Results were consistent with the interpretation that there is a relationship between being Chicano and having lower self-esteem, lower behavioral adjustment, and higher ethnic esteem. The prediction that ethnic esteem would mediate between ethnic group and self-esteem was upheld. Variables such as ethnic group membership per se and sex appear as or more important to the prediction of behavioral level. Clinical implications include recognizing that Chicanos low in self-esteem or behavioral adjustment should not automatically be considered unusual. The problems faced by this group are considered as having something in common with other groups of people who have more problems, lesser status, fewer resources, and fewer sources of available help.

Adolescent↗

PubMed1976

[Analogs and models of systemic arterial circulation].

This review article is primarily aimed at those researches using the experimental physiological approach and gives a survey of analogs and models of the systemic arterial blood flow. They are presented in increasing order of complexity in two sections: the "lumped" and the "distributed" parameter models. In the first section a brief description is given of the purely resistive, Windkessel and multi-element analogs with emphasis on their use in physiology for estimating several hemodynamic variables. The distributed parameter models, whose central idea is pulse wave propagation along the arterial tree, are then presented in five categories, using a new classification scheme. These categories are based on four criteria derived from the assumptions used in the formulation of the fluid and wall equations. The most recent non-linear models are treated in more detail with their common properteis as well as their particular contribution emphasized. In conclusion it is noted that the distributed parameter models also begin to be used to evaluate physiological variables in the experimental and clinical context and that this trend can only become more important in view of the advances made in the field of biomedical instrumentation.

Animals↗

PubMed1995

Implications for the alcohol/drug education specialist working with children of alcoholics: a review of the literature from 1988 to 1992.

This article reviews the scientific literature on children of alcoholics (COAs) from 1988 to 1992. First the publications were divided into two classifications: practitioner-oriented and research-oriented literature. Each practitioner-oriented article was evaluated on the following criteria: program description, theoretical model, recommendations substantiated by research, behavioral indicators of COAs, suggestions for intervening, and resource lists. For each of the research-oriented articles, the variables measured, sample source, sample size, and number of COAs in the sample are listed. Additionally, those articles are evaluated for research design, instruments, and analytical techniques. Reviews of early research in this area identified severe methodological limitations across the majority of articles. However, results of this more recent review indicate that research on COAs no longer suffers from previously common methodological weaknesses and sampling biases. The research-based literature also indicated that a larger number of COAs are resilient, which calls into question common assumptions about the inevitable negative effects of familial alcoholism. Alcohol/drug education specialists need to be cognizant of the more recent results on non-clinical samples of COAs in designing and implementing sensitive programs.

Alcoholism↗

PubMed2006

The effect of discordance among violence and general recidivism risk estimates on predictive accuracy.

INTRODUCTION: Previous research has shown that the prediction of short-term inpatient violence is negatively affected when clinicians' inter-rater agreement is low and when confidence in the estimate of risk is low. This study examined the effect of discordance between risk assessment instruments used to predict long-term general and violence risk in offenders. METHODS: The Psychopathy Checklist - Revised (PCL-R), Level of Service Inventory - Revised (LSI-R), Violence Risk Appraisal Guide (VRAG), and the General Statistical Information on Recidivism (GSIR) were the four risk-prediction instruments used to predict post-release general and violent recidivism within a sample of 209 offenders. RESULTS: The findings lend empirical support to the assumption that predictive accuracy is threatened where there is discordance between risk estimates. Discordance between instruments had the impact of reducing predictive accuracy for all instruments except the GSIR. Further, the influence of discordance was shown to be greater on certain instruments over others. Discordance had a moderating effect on both the PCL-R and LSI-R but not on the VRAG and GSIR. CONCLUSIONS: There is a distinct advantage when attempting to predict recidivism to employing measures such as the LSI-R, which includes dynamic variables and intervention-related criminogenic domains, over a measure purely of fixed characteristics, such as the GSIR; however, if there is discordance between the risk estimates, caution should be exercised and more reliance on the more static historically based instrument may be indicated.

Adolescent↗

PubMed1981

Are prejudices against disabled persons determined by personality characteristics? Reviewing a theoretical approach on the basis of empirical research findings.

Taking as point of departure the results obtained from research on prejudice, many authors believe that the quality of attitudes toward disabled persons is influenced by the personality structure of the nondisabled. In order to verify this assumption, a secondary analysis of 67 empirical studies was undertaken. These studies referred to different personality variables such as authoritarianism, ethnocentrism, dogmatism, rigidity, intolerance of ambiguity, cognitive simplicity, anxiety, ego-weakness, self-concept, body-concept, aggressiveness, empathy, intelligence, etc. The results can be summarized as follows: Statistical criteria show that single personality traits have relatively little influence on the attitudes towards disabled persons. An adequate evaluation of the research findings is complicated by, at times, considerable methodological problems which arise when applying the proper test instruments to non-clinical populations. Marked correlations are to be found in particular in the case of authoritarianism, ethnocentrism, intolerance of ambiguity, anxiety, and ego-weakness. The intercorrelations, however, between most of the personality variables are rather high, which by cumulation of "extreme" factors may, in fact, sometimes result in particularly unfavorable attitudes toward the disabled. Thus, personality-related research findings to provide certain valuable explanations. Special attention should be devoted to the multiple connections between personality structure and social structure.

Attitude to Health↗

PubMed2002

Spatial patterns of tuberculosis incidence in Cologne (Germany).

In many European countries, the decline of tuberculosis notification rates levelled off in the mid 1980s. Germany has been facing only a very modest resurgence of tuberculosis (TB) in the early 1990s, but until now, the notification rate does not yet fulfil the WHO definition of a low incidence country. Mainly immigration from high incidence countries is held responsible for the delayed decline and temporary increase of TB. This paper seeks to investigate the inner-urban strength of association between tuberculosis and several potential risk factors in the city of Cologne using geographical and statistical methods within a small-area division based, GIS-supported ecological study, which never before has been conducted for a German city. Standardised annual TB incidence rates for 78 urban subdistricts between 1986 and 1997, disaggregated by age, have been analysed. Twelve independent variables representing contemporary ethnic and socioeconomic conditions are used to calculate Poisson regression models. For the entire population and for the <60 age group, a strong positive association was found between tuberculosis incidence and share of immigrants. Interestingly enough the share of German-origin immigrants from eastern Europe was seen not to be instrumental in increasing TB rates. Reflecting strong ecological correlations between variables depicting economic conditions and TB as well as immigration variables, the deprivation of certain ethnicities rather than high prevalence immigration background is inferred to be significant to TB level. As for the 60 + age group regression analysis fails to model the TB incidence patterns sufficiently it seems reasonable to assume an autonomous, spatially disaggregated TB epidemic of the elderly, echoing a severe post-war epidemic by reactivation, only marginally associated with contemporary living conditions, but contributing substantially to the current TB incidence level. This assumption is reinforced by further results of the statistical analysis (deviance of regression null models, testing for Normal distribution, time trends). It could be shown that in Cologne the HIV/AIDS epidemic is not significantly influencing the TB incidence rate of men aged 30-49 being the most AIDS-afflicted population subgroup.

Adult↗

PubMedDate not supplied

Sonometric evaluation of eustachian tube function using broadband stimuli.

New measurements of acoustical transmission through the eustachian tube (ET) have been obtained in a series of experiments directed toward the development of a clinical instrument to assess ET function behind an intact tympanic membrane (TM). Using a sound conduction method, a sound source was placed in one nostril, and the acoustical energy that was transmitted through the ET was measured by a microphone placed in the ear canal. The present study used a broadband noise as the acoustical stimulus, in contrast to the tonal stimuli employed in previous investigations. This stimulus was chosen because it is believed to reduce the variability in the data due to intersubject differences in the acoustics of the nasopharynx and ET, and to avoid any a priori assumptions concerning the specific frequencies that would be of greatest diagnostic significance. Averaged spectra of the sound transmitted to the ear canal were obtained for three experimental conditions: acoustical source present during subject swallowing, source present with no swallowing, and subject swallowing with source absent. A Bayesian classification scheme based on the statistics of these spectra was used in classifying subjects into one of two possible categories, normal and abnormal ET function. A comparison was made between sonometric classification and classification based on a tympanometric ET function test. Correlation between the two methods was 87.1%.

Acoustic Impedance Tests↗

PubMed1985

Perceived parental rearing behaviour in unipolar and bipolar depressed patients. A verification study in an Italian sample.

Two groups of former depressed Italian patients comprising 54 bipolars and 52 unipolars completed the Italian version of the EMBU, a Swedish instrument aimed at assessing the experience of parental rearing behaviour. As in a previous study of Swedish depressives, three factors, "rejection", "emotional warmth", and "over-protection", have been taken into account. The results obtained in the patient group have been compared with those obtained in Italian healthy controls. Depressed patients rated both parents significantly lower than the controls on the factor "emotional warmth". The present results cross-validate those obtained previously in the Swedish depressives and strengthen, together with other findings in the literature, the assumption that the lack of emotional warmth in the parents' rearing practices might be a crucial variable in the pathogenesis of depressive illnesses.

Attitude↗

PubMed1986

Dental anxiety--the development of a measurement model.

A more detailed measurement instrument for dental anxiety has been developed. To investigate the dimensionability of the response, two instruments were administered to 452 persons. The first set of items (33) concerned stimuli which might prove fearsome to patients. Some of these were dental specific, others were not. A second instrument (20 items) elicited the anxiety symptoms experienced. By comparing separate Kaiser-Caffrey Alpha Factor Analyses two factors were identified within each instrument. These were labelled "generalized" phobias and "dental specific" phobias; and "endogenous" and "exogenous" (anticipatory) anxiety symptoms. Four scales were constructed using simple summations of highly loaded variables. The scales are quite reliable. Although correlations among the scales proved to be significant they are all quite low, indicating that the four scales give more or less non-redundant information about the patient. The scale had discriminating validity in differentiating between patients who acknowledge experiencing spontaneous panic/anxiety attacks and those who did not. The data confirm that dental fears are relatively independent of other generalized anticipatory fears. The results cast doubt on previously held assumptions regarding the unidimensionality of anxiety. They are consistent with a new classification of anxiety and phobic disorders presented elsewhere. The implications for research and patient management are discussed.

Anxiety Disorders↗

PubMed2002

DNA microarrays and toxicogenomics: applications for ecotoxicology?

Toxicogenomics attempts to define how the regulation and expression of genes mediate the toxicological effects associated with exposure to a chemical. DNA microarrays are rapidly becoming one of the tools of choice for large-scale toxicogenomic studies. An approach in modern toxicogenomics has been to classify toxicity based on gene transcriptional patterns; comparing the transcriptional responses of a chemical with unknown toxicity to those for which the transcriptional profiles and toxicological endpoints have been well characterized. Recent evidence suggests that gene expression microarrays may be instrumental in defining mechanisms of action of toxicants. However, several assumptions are inherent to a toxicogenomic-based approach in toxicology, many of which remain to be validated. Gene expression profiling using DNA microarrays represents a snapshot of the gene transcriptional responses occurring at a particular time and within a particular tissue. Toxicity, on the other hand, represents a continuum of possible effects governed by both temporal and spatial factors that are inextricably contingent upon the exposure conditions. The perceived toxicological properties of any chemical are dependent on the route, dose, and duration of the exposure, and as such, gene expression patterns are also subject to these variables. Correct interpretation of DNA microarray data for the assessment of the toxicological properties of chemicals will require that temporal and spatial gene expression profiles be accounted for. These considerations are further compounded in ecotoxicological studies, during which altered gene expression patterns induced from exposure to an anthropogenic substance must be discernible over and above the complex effects that phenotypic, genotypic, and environmental variables have on gene expression. To this end, the greatest utility of DNA microarrays in the field of ecotoxicology may be in predicting the toxicological modes of action of anthropogenic substances on host physiology, particularly in non-model organisms. Predictable and accurate assessment of the impacts of a chemical substance in ecotoxicology will require that classical toxicological endpoints be used to validate any effects predicted based on gene expression profiling. Validated expression profiling may subsequently find utility in ecotoxicological-based computer simulation models, such as the Biotic Ligand Model (BLM), in which gene expression information may be integrated with geochemical, pharmacokinetic, and physiological data to accurately assess and predict toxicity of metals to aquatic organisms.

Journal Article↗

PubMed1967

The relation between heat produced and phosphorylcreatine split during isometric contraction of frog's muscle.

1. Heat production, tension development and phosphorylcreatine (PC) splitting have been measured simultaneously during isometric contractions of iodoacetate-poisoned frogs' sartorii at 0 degrees C. The muscles were stimulated to produce a series of 30 twitches or a 10 sec tetanus or a 30 sec tetanus.2. Of the several possible methods of calculating PC breakdown the best appears to be the one based on the assumption that PC/(total creatine) was originally the same in the two muscles of a pair.3. The difficulty of expressing PC break-down, heat production etc. in terms of the muscle's size is demonstrated.4. Several artifacts are discussed, including the heat produced by the stimulus and the possible role of reactions other than PC splitting.5. Even when these have been substantially eliminated there remains the rather intractable statistical problem of establishing a functional relationship between heat produced and PC split when both of these variables contain errors, so that ordinary regression analysis is misleading. It is shown that this problem can be dealt with satisfactorily by introducing other instrumental variables that can be determined experimentally.6. The final conclusion is that the in vivo enthalpy of hydrolysis of PC is about 10.6 kcal/mole, and is the same in twitches and in tetani.

Animals↗

PubMed2004

The Proview phosphene tonometer fails to measure ocular pressure accurately in clinical practice.

PURPOSE: To evaluate the Proview Eye Pressure Monitor as a medical instrument and as a technique for enabling a patient to obtain an accurate measure of his or her intraocular pressure (IOP). DESIGN: An experimental laboratory evaluation and an independent prospective clinical study to test the reproducibility and accuracy of the Proview technique relative to Goldmann applanation tonometry. PARTICIPANTS: For the laboratory study, we analyzed 3 tonometers, each packaged as a Proview Eye Pressure Monitor by Bausch & Lomb. In the independent prospective experimental study, 137 subjects participated, consisting of healthy volunteers and glaucoma patients. METHODS: For laboratory testing, we held each tonometer with a micrometer to assure controlled positioning and pressed its sensing tip against a force meter that produced a calibrated, digital force reading. For clinical testing, we taught subjects (n = 137) to use the Proview technique in accordance with the manufacturer's instructions. Each subject obtained 5 measurements with each of the 5 different Proview devices. A clinician measured the IOP using Goldmann applanation tonometry. MAIN OUTCOME MEASURES: We measured the absolute value, linearity, and repeatability of the force meter readings on the tonometers during the instrument laboratory evaluation. The accuracy was evaluated by comparing the Proview measurements to the Goldmann applanation measurements. Reproducibility of clinical Proview measurements was also measured. All measurements were in mmHg during the clinical evaluation. RESULTS: Laboratory: There was a linear relationship between the pressures read by the Proview tonometers and known forces. The Proview tonometers read the maximum pressure applied. Clinical: The Proview technique is simple to use because it was comfortable and reproducible, with an average variance of the measurements by the same patient of 3.4 mmHg(2). Other variables besides IOP seem to affect the Proview pressure measurements, as seen in the large scatter in our data, measured by our correlation coefficient of r = 0.41. The sensitivity of the Proview technique to detect patients with high IOP (which we defined as a Goldmann pressure of >/=22 mmHg) is low; the Proview pressure identified only 18% (4/22) of these patients. CONCLUSIONS: The Proview instrument and technique were reproducible. However, the Proview tonometer seems not to be reliable as an indicator of IOP. The sensitivity for detecting high IOP was low in this cohort, and the agreement with Goldmann applanation was poor for some individuals. This brings into question the underlying assumption that a force proportional to the IOP generates phosphenes.

Adolescent↗

PubMed2006

Income disparities in the quality of life of cancer survivors.

BACKGROUND: Studies of cancer survivors usually report positive correlations between income and health-related quality of life (QoL). These correlations cannot necessarily be interpreted as income disparities because earnings and income are affected by health, as well as the reverse. OBJECTIVES: The goal of this study was to quantify income disparities in QoL among cancer survivors by using instrumental variables (IV) to assess and, if necessary, correct for reverse causality. METHODS: We constructed an instrumental variable for income from home ownership, sources of unearned income, marital status at diagnosis, and spousal characteristics. Then, we examined income's effect on QoL in regressions controlling for other clinical and demographic predictors of QoL. The data were from interviews in 2002 with a cohort of cancer survivors who were 25 to 62 years of age when diagnosed during 1997 to 1999. MEASURES: The Functional Assessment of Cancer Therapy-General (FACT-G) and the SF-12 measured QoL in multiple domains. Questions adapted from the Health and Retirement Study ascertained the ratio of annual family income to the poverty threshold in 2001. RESULTS: Endogeneity tests were sensitive to assumptions of linearity for the income-QoL relationship and the choice of QoL measure. Consistently estimated income disparities were significant in all QoL models. The income elasticity of QoL ranged from 2% to 10%. CONCLUSIONS: There are income-related disparities in the QoL of cancer survivors that cannot be explained away by the effect of health on earnings. High-income patients are not only more likely to survive cancer, but they enjoy better QoL as survivors.

Adult↗

PubMed2001

Institutionalization of demented elderly: the role of caregiver characteristics.

BACKGROUND: Three sets of caregiver characteristics were examined with respect to their explanatory value for institutionalization of demented elderly people: commitment to the caregiving relationship, psychological distress, and personality traits. METHOD: Logistic regression was used to test whether these caregiver characteristics were risk factors for institutionalization of demented elderly people in the first year after baseline measurement (N = 138). Control variables were caregivers' sex, age and education. RESULTS: The results showed the importance of commitment to the caregiving relationship, indicated by type of relationship between caregiver and care recipient. Demented people cared for by non-spouses were more likely to be institutionalized as compared to those cared for by spouses. For non-spouse care-givers, being more extravert increased the likelihood of institutional placement, whereas for spouse caregivers perceiving more pressure from informal increased this likelihood. CONCLUSIONS: These findings are in agreement with the assumption that non-spouses are less strongly committed to the caregiving relationship as compared to spouses. Results were independent from elders' impairment in cognitive functioning and (Instrumental) Activities of Daily Living. Caregivers' psychopathology was not a risk factor at all, which is a matter of concern, regarding the consequences for caregivers' own health and health-care utilization, but also for their treatment of the demented elder.

Aged↗

PubMed1986

A comparative study of adult developmental patterns of RN and generic students in a baccalaureate nursing program.

The current influx of RN students into baccalaureate nursing programs has led to many curriculum changes that are based on the unverified assumption that the RN students are "different." This study examined the differences and similarities among RN and generic nursing students using a conceptual framework designed by Weathersby (1977) which incorporated into a single framework Levinson's life stage, Loevinger's ego development, and Kolb's learning styles theories in order to trace the adult development patterns of generic and RN students. Three instruments were used: The Washington University Sentence Completion Test, the Kolb Learning Style Inventory, and Tarule's Educational Experience Inventory. The sample consisted of 49 RNs and 30 generic students enrolled at a large southern state university. The results of the analyses revealed significant difference between RN and generic students on the variables life stages and ego development but not on learning styles. These results substantiated the premise that RN and generic students differ significantly in their stages of adult development, and consequently affect the students' perception and expectations of the educational process.

Adult↗

PubMed1986

Peripheral circulatory alterations in canine anaphylactic shock.

We have examined peripheral circulatory variables that might contribute to the decrease in cardiac output and arterial pressure characteristic of anaphylactic shock. In six dogs instrumented with a right heart bypass, the intravenous administration of Ascaris suum antigen caused a 53% decrease in cardiac output and a 58% decrease in arterial pressure. Resistance to venous return increased from 0.0038 +/- 0.0004 to 0.0056 +/- 0.0006 mmHg X ml-1 X min (P less than 0.05), mean systemic pressure decreased from 7.0 +/- 0.6 to 4.4 +/- mmHg (P less than 0.005), and vascular compliance did not change. Assuming a constant vascular volume, the decrease in mean systemic pressure could be explained by a rightward shift of the systemic pressure volume curve. This constant-volume assumption was tested in intact (n = 6) and splenectomized dogs (n = 7). Serial measurements of protein oncotic pressure and hematocrit were used to estimate plasma volume changes during anaphylaxis. Both methods for estimating volume showed small increases in plasma volume at the time of the largest decrease in arterial pressure in both groups of animals. These results suggest that the primary circulatory mechanisms responsible for anaphylactic shock are an increase in resistance to venous return and a shift of the systemic pressure volume curve and not an acute loss of plasma volume.

Anaphylaxis↗

PubMed1990

[A study of factors influencing the state of adaptation of hemiplegic patients].

The purposes of this study are to delineate a profile of the state of a stroke patient's adaptation at 3 months after hospitalization and to explore the relationship between the level of adaptation and the variables which influence the adaptation of hemiplegic patients. To these ends, theoretical framework was derived basically from the stress adaptation model. The basic assumption underlying the level of adaptation is influenced by the presenting focal, contextual and residual stimuli. This group of stimuli is further operationalized and represented by a perception of stress, which is the perceived effect of the disability and by the mediating variables such as sociodemographic factors as an external conditioning variables and perceived social support and hardiness personality characteristics as an internal intervening variables. The dependent variables in this study is the level of physical, psychological and social adaptation and is hypothesized to be a function of the interaction between 3 sets of variables namely, the perceived disability effect, external conditioning variables and internal intervening variables. A total of fourty three subjects from 3 general hospitals in Seoul were observed and interviewed with the aid of 7 structured instruments. The data were collected twice on each subject: first, at the pre-discharge period and at 3 months post-discharge from hospital for the second time. The study was carried out for the period from February to August, 1988. The instruments used for the study include 4 existing scales and 3 scales developed by the researcher for this study. They are: 1) The ADL dependency scale and the scale of the clinical physical functions for the assessment of physical adaptation. 2) the SDS (self report of depression) to measure the level of psychological adaptation. 3) The scale for the amount of social activities for the measurement of the level of social adaptation. 4) The scale for the perceived effect of disability for the measurement of the focal stimuli. 5) The health related hardiness scale and the perceived interpersonal support self evaluation list (ISEL) for the measurement of the hardiness personality character and the perceived social support. The data obtained were analyzed using percentage, one way ANOVA, Pearson coefficients correlation and stepwise multiple regression. The findings provide valuable information about the present level of physical adaptation at 3 months after discharge. The patient revealed a decreased ADL dependency and lowered limitation of physical function as compared with pre-discharge state. Psychologically, the average degree of depression at follow up was within normal range of depression.(ABSTRACT TRUNCATED AT 400 WORDS)

Activities of Daily Living↗

PubMed2007

Interval estimation for rank correlation coefficients based on the probit transformation with extension to measurement error correction of correlated ranked data.

The Spearman (rho(s)) and Kendall (tau) rank correlation coefficient are routinely used as measures of association between non-normally distributed random variables. However, confidence limits for rho(s) are only available under the assumption of bivariate normality and for tau under the assumption of asymptotic normality of tau. In this paper, we introduce another approach for obtaining confidence limits for rho(s) or tau based on the arcsin transformation of sample probit score correlations. This approach is shown to be applicable for an arbitrary bivariate distribution. The arcsin-based estimators for rho(s) and tau (denoted by rho(s,a), tau(a)) are shown to have asymptotic relative efficiency (ARE) of 9/pi2 compared with the usual estimators rho(s) and tau when rho(s) and tau are, respectively, 0. In some nutritional applications, the Spearman rank correlation between nutrient intake as assessed by a reference instrument versus nutrient intake as assessed by a surrogate instrument is used as a measure of validity of the surrogate instrument. However, if only a single replicate (or a few replicates) are available for the reference instrument, then the estimated Spearman rank correlation will be downwardly biased due to measurement error. In this paper, we use the probit transformation as a tool for specifying an ANOVA-type model for replicate ranked data resulting in a point and interval estimate of a measurement error corrected rank correlation. This extends previous work by Rosner and Willett for obtaining point and interval estimates of measurement error corrected Pearson correlations.

Confidence Intervals↗