SEARCH · PubMed Health

Results for “Model explainability”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,603 records · Page 89Linked to original sources

PubMed1983

Physicians' opinions of expanded clinical pharmacy services.

A statistical interaction model explaining 27 per cent of the variation in physicians' attitudes toward clinical pharmacy among 180 Alabama physicians is presented. Young primary care physicians who prescribe drugs with a low risk of adverse reactions are the most favorable toward pharmacists practicing clinical tasks. Older solo-practice physicians who lack exposure to clinical pharmacy are the least favorable. The implications for the wider acceptance of clinical pharmacy are discussed in terms of its resources of professional power. (Am J Public Health 1983; 73:96-101.)

Adult↗

PubMed2003

Contextual influences on reproductive wellness in northern India.

OBJECTIVES: There has been a growing recognition of the importance of contextual influences on health outcomes. This article examines community-level influences on 5 reproductive wellness outcomes in Uttar Pradesh, India. METHODS: Multilevel modeling is used to estimate household and community-level effects on wellness, with hierarchically organized data from a statewide survey of villages, urban blocks, households, women, health providers, and staff. RESULTS: The household and community have a strong contextual influence on wellness, although the models explain more of the variation in outcomes between households than between communities. CONCLUSIONS: Communities influence wellness outcomes through the socioeconomic environment and the characteristics of the health infrastructure. The specific dimensions of the community and health infrastructure varied between the outcomes.

Adolescent↗

PubMed2002

Magnification in excess of 100-times of the microscopic photothermal lensing signal from solute molecules by two-color excitation with continuous-wave lasers.

A microscopic photothermal lensing measurement under two-color continuous-wave laser excitation was performed to investigate a signal enhancement owing to the transient absorption by photoexcited solute molecules in liquid solutions. An intensity-modulated 409 nm laser beam and an un-modulated 532 nm laser beam were used for excitation, and a 670 nm probe beam was used for detecting the modulation amplitude of thermal lensing signals generated with a microscopic objective lens focusing laser beams into a capillary flow cell of 0.1 mm optical path length. The amplitude of the modulated signal increased as the power of the un-modulated laser beam increased, and a 143-times magnification was observed for an iso-propanol solution of naphthacene having 4.6 x 10(-4) absorbance at 409 nm and a negligible absorbance at 532 nm. A four-level model explaining the signal enhancement is proposed, and an important role of the transient absorption by photoexcited molecules is discussed.

Journal Article↗

PubMed2004

Structure-activity relationships of histamine H2 receptor ligands.

Recent research on histamine H2 receptor agonists was focused on quantitative structure-activity relationships and receptor models explaining the activity of imidazolylpropylguanidines. Their selectivity for guinea pig vs. human isoforms was investigated using H2 receptor-Gsalpha fusion proteins and attributed to amino acid differences in transmembrane domains 1 and 7. New antagonists result from approaches to improve pharmacokinetic properties and to design hybrid drugs which additionally have gastroprotective or anti H. pylori activity.

Animals↗

PubMed2002

Molecular and cellular tools in human cystic echinococcosis.

The latest developments in the molecular and cellular mechanisms that underlie Echinococcus infection have renewed interest in the immunodiagnosis of this disease and have helped in understanding the host-parasite relationship. This review discusses current concepts on the immune response to Echinococcus granulosus in humans, and relates these findings to diagnosis and clinical management. The two most promising molecular tools developed for the immunodiagnosis of cystic echinococcosis involve isolating native or recombinant parasite antigens to detect specific serum antibodies in patients with suspected echinococcosis and producing monoclonal antibodies to detect parasite antigens in clinical samples. Novel drugs should be designed to strengthen host immune responses thus combating parasitic survival. Currently, attention has been focused on understanding T-helper lymphocyte activity; in particular the role of Th1 and Th2 subsets in orchestrating immune responses. The Th1/Th2 model explaining how selective immune responses--including cell-mediated or humoral immunity--develop, seems promising as the rationale for molecular tools that could lead to new therapeutic strategies.

Animals↗

PubMed1989

A path analytic examination of differential social control theory.

Differential social control theory was investigated with survey data from 860 adolescents using path analytic techniques. Peer non-use expectations, peer use, and the adolescent's own attitude each have a direct influence on drug use. Peer non-use expectations have the largest total effect on drug use and are directly influenced by parental, peer, and school attachments. Student's attitude has a direct effect on drug use, however, a majority of the association is spurious. Peers' drug use has the largest, direct influence on drug use. The likelihood of adolescents' associating with drug using friends is reduced by a close relationship with their parents and by knowing that their friends disapprove of drug use. The model explained 60 percent of the variance. Students do not use drugs if they are unwilling to jeopardize their relationship with their parents and non-using friends. They are also less likely to use drugs if they think their parents and friends disapprove of drug use and if their friends do not use drugs themselves.

Adolescent↗

PubMed1988

Finances of unmarried elderly people over time.

This research assessed the effect of widowhood, divorce, and life-long singleness on income and evaluations of finances at two points, and investigated factors associated with satisfaction with level of living in old age. Data were analyzed from two interviews with 2,047 older, unmarried men and women. Models explaining satisfaction with level of living were relatively similar for the marital status groups. Marital status affected the economic circumstances and perceptions of finances of women more often than men. The strains of divorce and widowhood for women and divorce for older men had an enduring influence on finances, and in the instance of men, were heightened over time.

Adult↗

PubMed2005

Automated assessment of the quality of depression websites.

BACKGROUND: Since health information on the World Wide Web is of variable quality, methods are needed to assist consumers to identify health websites containing evidence-based information. Manual assessment tools may assist consumers to evaluate the quality of sites. However, these tools are poorly validated and often impractical. There is a need to develop better consumer tools, and in particular to explore the potential of automated procedures for evaluating the quality of health information on the web. OBJECTIVE: This study (1) describes the development of an automated quality assessment procedure (AQA) designed to automatically rank depression websites according to their evidence-based quality; (2) evaluates the validity of the AQA relative to human rated evidence-based quality scores; and (3) compares the validity of Google PageRank and the AQA as indicators of evidence-based quality. METHOD: The AQA was developed using a quality feedback technique and a set of training websites previously rated manually according to their concordance with statements in the Oxford University Centre for Evidence-Based Mental Health's guidelines for treating depression. The validation phase involved 30 websites compiled from the DMOZ, Yahoo! and LookSmart Depression Directories by randomly selecting six sites from each of the Google PageRank bands of 0, 1-2, 3-4, 5-6 and 7-8. Evidence-based ratings from two independent raters (based on concordance with the Oxford guidelines) were then compared with scores derived from the automated AQA and Google algorithms. There was no overlap in the websites used in the training and validation phases of the study. RESULTS: The correlation between the AQA score and the evidence-based ratings was high and significant (r=0.85, P<.001). Addition of a quadratic component improved the fit, the combined linear and quadratic model explaining 82 percent of the variance. The correlation between Google PageRank and the evidence-based score was lower than that for the AQA. When sites with zero PageRanks were included the association was weak and non-significant (r=0.23, P=.22). When sites with zero PageRanks were excluded, the correlation was moderate (r=.61, P=.002). CONCLUSIONS: Depression websites of different evidence-based quality can be differentiated using an automated system. If replicable, generalizable to other health conditions and deployed in a consumer-friendly form, the automated procedure described here could represent an important advance for consumers of Internet medical information.

Australia↗

PubMed2001

A major gene effect on fasting insulin and insulin sensitivity in familial combined hyperlipidemia.

The most common inherited dyslipidemia, familial combined hyperlipidemia (FCHL), is associated with insulin resistance. Whether insulin sensitivity in these families is inherited is not known. Therefore, we investigated the inheritance of insulin sensitivity in 352 nondiabetic family members from 37 families with FCHL, 105 of whom had undergone testing using the hyperinsulinemic-euglycemic clamp technique for the measurement of insulin sensitivity. First, complex segregation analysis of fasting insulin levels (both unadjusted and age-, age(2)-, and BMI-adjusted) was used for modeling of the variance in fasting insulin levels. In these analyses, Mendelian codominant inheritance (P = 0.320 for unadjusted and P = 0.295 for adjusted insulin values) was not rejected over the most general model and fit the data significantly better than the sporadic model (P < 0.001). Polygenic and environmental models were rejected (P < 0.001). The Mendelian codominant model explained 44 and 45% of the variance in unadjusted and adjusted fasting insulin levels, respectively. The proposed genotypes of this locus, based on segregation analysis, were associated with directly measured insulin sensitivity in 105 FCHL family members who underwent the hyperinsulinemic-euglycemic clamp (P < 0.001). These results provide evidence for a major gene regulating insulin sensitivity in FCHL families. Possible pleiotropic effects of this insulin sensitivity locus on dyslipidemias in FCHL remain to be elucidated.

Adult↗

PubMed2005

Prediction of outcome after ankle fracture.

STUDY DESIGN: Prospective inception cohort study of 62 consecutive patients seen in 2 orthopaedic clinics following ankle fracture. OBJECTIVES: To investigate 4 putative predictors (age, fracture classification, acute management [surgical or nonsurgical], and ankle dorsiflexion range of motion measured at the time of cast removal) of outcome after ankle fracture and to develop simple predictive models of outcome after ankle fracture. BACKGROUND: Ankle fracture is a common condition. However, few studies have investigated factors that predict outcome after ankle fracture. METHODS AND MEASURES: Sixty-two consecutive subjects aged 17 or older with ankle fractures were recruited from 2 hospital orthopaedic clinics. Outcome measures recorded at 6 weeks and 6 months after cast removal included 2 functional questionnaires, patients' ratings of global improvement, and a measure of ankle dorsiflexion. The predictive value of 4 variables selected a priori was analyzed using bivariate and stepwise multiple linear regression. RESULTS: Ankle dorsiflexion and fracture classification predicted outcome 6 weeks and 6 months after cast removal for all outcome measures used (P < .05, r2 = 0.09-0.47). Fracture management (surgical or nonsurgical) inconsistently predicted outcome at both 6 weeks and 6 months, and age did not predict outcome at either 6 weeks or 6 months after cast removal. The predictive models explain between 19% and 58% of the variance in outcomes 6 weeks after cast removal and 19% to 52% of the variance in outcomes 6 months after cast removal. CONCLUSION: Ankle dorsiflexion measured at the time of cast removal and fracture classification are clinically significant predictors of outcome after ankle fracture; however, much unexplained variation in outcomes still exists.

Adolescent↗

PubMed1990

Performance of crosses among Hereford, Angus and Simmental cattle with different levels of Simmental breeding: IV. Maternal heterosis and calf production by two-year-old dams.

The performance of 264 contemporary 2-yr-old straightbred and crossbred dams during 1978 to 1981 was studied and maternal heterosis was estimated. Dam breed groups were Hereford (HH), Angus-Hereford (AH), 25% Simmental-75% Hereford (1S3H), 50% Simmental-50% Hereford (1S1H) and 75% Simmental-25% Hereford (3S1H). Differences among dam breed groups were nonsignificant for length of gestation, calving difficulty and late milk production but were important (P less than .01) for calf weights (birth, early and late milking periods and weaning), calf average daily gains during various intervals from conception to weaning, early milk production and other calf traits at weaning (height, weight/height and visual condition score). Dam breed group means (HH, AH, 1S3H, 1S1H and 3S1H, respectively) for representative calf traits were .37, .39, .39, .42 and .42 kg/d for estimated average daily gain the last 3 mo of gestation; 33.6, 34.7, 35.7, 37.6 and 37.1 kg for birth weight; 191, 205, 209, 228 and 228 kg for weaning and 7.5, 8.4, 8.3, 9.5 and 10.0 kg for 24-h early milk production. Therefore, 2-yr-old crossbred dams raised calves that were generally larger for the preweaning gain traits than HH dams. Differences among dam breed groups were significant for traits involving reproduction; means (HH, AH, 1S3H, 1S1H and 3S1H, respectively) were .58, .92, .72, .91 and .79 for proportion calving and 105, 179, 126, 182 and 154 kg for actual calf weaning weight per cow exposed to breeding. Estimates of percentage maternal heterosis were 6.3, 12.9, 9.0 and 7.6% for calf weights at birth, 40 d, 130 d and weaning, respectively; 1.8, 5.7 and 5.7% for calf hip height, height/weight and condition score at weaning, respectively; and 43.1 and 34.6% for proportion calving and actual calf weaning weight per cow exposed to breeding. The dominance model explained most (greater than 95%) of the variation observed among dam breed group means for most traits.

Animals↗

PubMed1996

Receptorpharmacological models for the therapy of labyrinthine vertigo.

In the mammalian labyrinth, GABAA receptor subtypes are involved in the excitatory neurotransmission between the vestibular type II hair cells and the afferent neurons. Additional afferent ionophoric receptor channels, sensitive to further transmitter candidates, are discussed for both types I and II hair cells. GABA accelerates excitotoxic cell death in cortical neurons. This GABA-ergic neurotoxic action forms an appropriate pathophysiological model explaining peripheral labyrinthine disorders characterized by the spontaneous labyrinthine nystagmus and vertigo in man. A calculated GABAA receptor antagonism was envisaged in order to attenuate the pathological vestibular imbalance following one-sided GABA-accelerated vestibular neurotoxicity. Moderate allosteric blockers of the GABAA receptor channel and weak inverse agonists of the benzodiazepine binding site meet some requirements for potentially successful clinical application. The suppressing action of the suitable drugs picrotoxin and flumazenil on labyrinthine nystagmus and vertigo, tested in clinical trials, supports the hypothesis that GABAA receptors are involved in vestibular neurotransmission, even in humans. The test results promise the development of a successful vestibular receptorpharmacology in the near future.

Binding Sites↗

PubMed1996

Underprivileged area score, ethnicity, social factors and general mortality in district health authorities in England and Wales.

OBJECTIVE: To analyse the relation of ethnicity, social deprivation (Underprivileged area, UPA-score), social class V, unemployment and overcrowding on age- and sex-standardized mortality ratio (SMR). DESIGN: This ecological study used the SMR for people under the age of 65 years as dependent variable. Mortality data for 1983, classified by total population of country of birth (New Commonwealth and Pakistan), unskilled (social class V), unemployed, and overcrowded (>1/room) population with data from 1981 censuses. Underprivileged Area (UPA) score was applied in this study, an index widely used in the UK to identify underprivileged residential areas, calculated from information combining eight variables derived from the decennial census. The data were analysed by multiple regression (least square estimation) with SMR as dependent variable and the other social factors as independent variables. SETTING: All 192 district health authorities in England and Wales. RESULTS: There was a significant association between UPA-score and SMR (R-square = 0.53, p = 0.0001). The second model included the four variables: % unskilled, % unemployed of economically active population, % of residents living in overcrowded households, and % of population from New Commonwealth and Pakistan. This model explained about 77% of the variance. All variables were significant. All coefficients except ethnicity were positive, i.e. the higher the coefficients, the higher the SMR. CONCLUSION: This paper shows that social deprivation, unemployment and overcrowding were related to mortality in district health authorities in England and Wales. The finding that ethnicity was inversely related to general mortality might be important and needs to be further analysed.

Adolescent↗

PubMedDate not supplied

The ICIDH: health problems in a medical and social perspective.

The ICIDH is a classification of health problems. Impairments, disabilities, and handicaps are to be considered as three different interpretations of a person's health state. Use of the ICIDH is indicated when a person's health problems need to be described at a particular point in time, both in medical and in social terms, i.e. including their significance for the daily life functioning of the patient. It is argued that the ICIDH is relevant to health problems other than just those for disabled and for chronically ill. The ICIDH subtitle and the model explaining the relations between disease and impairment-disability-handicap do not reflect a clear notion of the perspective of the ICIDH on health problems. An overview of ICIDH applications shows that the ICIDH is being used not so much for the evaluation of the health-care system but for many other purposes, among these the understanding of therapeutic activities.

Delivery of Health Care↗

PubMed1995

Smoking cessation leads to reduced stress, but why?

Recent longitudinal studies have demonstrated that smoking cessation leads to reduced feelings of stress. This finding is not predicted by either of the two main models for smoking behavior. The nicotine resource model (Warburton) states that nicotine is used to cope with external stressors, and predicts that smokers will suffer from increased stress when they quit smoking. The deprivation reversal model (Schachter), suggests that smoking reverses the deleterious effects of deprivation; cessation will then lead to a period of increased stress, followed by a return to baseline. Although the stress/cessation data agree with neither model, they are consistent with a third explanation, namely that smoking causes stress. This model states that acute nicotine deprivation (i.e., between cigarettes) leads to increased stress. Smokers then use cigarettes to reverse these withdrawal effects and "normalize" their mood. This model explains some paradoxical aspects of the smoking/mood relationship. First, why smokers are calmed by smoking, yet report high average levels of stress. Second, why stress levels become reduced after smoking cessation; this is because the former smoker no longer suffers from the adverse mood effects of acute nicotine depletion.

Adaptation, Psychological↗

PubMed2001

Evaluation of clinical and clinical chemical parameters in periparturient cows.

Certain blood parameters and clinical symptoms have been connected with milk fever and a hypocalcemic condition in the cow. The present study intended to establish a mutual connection between relevant blood parameters and potentially valuable background information about the cow and its observed clinical symptoms at calving. Two veterinarians were summoned within 12 h of parturition of 201 cows, distributed among 41 Danish commercial herds. Cows were at different parity levels (2 to 10) and breeds and management differed broadly among herds. A blood sample was taken from the vena jugularis or the tail vein and was subsequently analyzed in the laboratory. Furthermore, 13 different clinical symptoms were recorded as categorical data. We investigated associations among the data obtained. We assessed an interpretative model for actual blood calcium level with blood parameters and background knowledge of the animals. We established a path analysis using background knowledge, blood parameters, and results of clinical examinations to uncover causal connections among the variables. Twenty-six percent of the animals were diagnosed as having milk fever and subsequent blood analyses revealed a high frequency of hypocalcemia within the general range from 0.69 to 2.73 mmol of Ca per liter. Rectal temperature, inorganic blood phosphate, and potassium were all directly correlated with blood calcium, while glucose, lactate, and magnesium were inversely associated with calcium. Blood osteocalcin was significantly lower in hypocalcemic animals, indicating that de novo synthesis of bone was arrested during hypocalcemia. A mixed effect linear interpretative model explained 75% of the variation in blood calcium. Clinical symptoms like mood, appetite, muscle shivering, rumen motility, and paresis were individually correlated with blood calcium and were thereby predictive of hypocalcemia. The path analysis showed the central role of calcium in affecting the clinical symptoms. However, several other factors contributed to hypocalcemia.

Animals↗

PubMed2002

Repeatability of objective measurements on the rear legs of dairy cows.

The objective of this paper was to estimate the repeatability of objective measurements on the rear legs of dairy cows to see whether higher repeatability estimates could be obtained compared to the corresponding subjective linear score. Between September and November 1998, seven measurements of distance among dewclaw, hip, hock, pinbone, and thurl were taken on 73 cows from the University of Illinois dairy farm. Measurements were combined to define triangles and therefore angles reflecting rear leg structure. Three novice evaluators participated in the experiment, and, on a given day, two sets of measurements were taken by two evaluators. Cows were measured twice at a 1- to 4-wk interval. Size, evaluator, and order of measurement were included in the model as fixed effects. Cow, interactions of cow x evaluator and cow x order of measurement were random effects included in the model. The model explained over 80% of the variation for each variable. Repeatability estimates of the length measurements ranged from 0.61 to 0.89. Repeatability estimates of angles were much lower ranging from 0.00 to 0.24. The variation in natural standing position of the cow hampered the accuracy of the objective measurements. Low estimates of repeatability for angles describing rear leg suggested that objective measurements by novice evaluators were not sufficiently reliable to potentially replace the subjective linear score for rear leg curvature determined by experts. Usefulness of further investigation to find objective measurements that would give a better description of rear legs conformation compared to the corresponding current type trait was questionable.

Aging↗

PubMed1991

Effect of temperature on colostrometer readings for estimation of immunoglobulin concentration in bovine colostrum.

Effect of temperature on colostrometer readings for estimation of immunoglobulin concentration in bovine colostrum was investigated. Twenty-five colostrum samples were collected within 24 h postpartum from Holstein cows. Immunoglobulin concentration of colostrum was measured using a colostrometer through 5 degrees C increments from 0 to 40 degrees C. Two technicians measured independently a total of 225 samples. The agreement between technicians' readings was high (r = .98); thus, readings were averaged and used in regression analysis. A final regression model explained 92.5% of the total variation: corrected reading at 20 degrees C = uncorrected reading - 13.2 + .8 x temperature (degrees C). The regression equation was used to develop a conversion chart for practical field use.

Animals↗