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Confounding Factors (confounding + factor)
Kinds of Confounding Factors Selected AbstractsConfounding Factors in Infant Pain Assessment During Recovery From AnesthesiaJOURNAL FOR SPECIALISTS IN PEDIATRIC NURSING, Issue 2 2003Madalynn Neu ISSUES AND PURPOSE. To investigate in what ways infant pain assessments differed between outpatient surgical recovery areas (OPSRA) and other clinical settings that included inpatient postsurgical recovery areas. METHODS. Using a qualitative descriptive design, 8 nurse participants working in OPSRA and 7 nurse participants working in other clinical settings were interviewed. RESULTS. The assessments of participants in the OPSRA differed from those of other participants and were confounded by effects of a short-acting anesthetic, lower expectations of pain, and several extraneous factors. PRACTICE IMPLICATIONS. Recognizing infant pain in OPSRA is complex. Nurses working in OPSRA may need to assume leadership to address issues relating to accurate identification of infant pain and alleviating extraneous factors that may influence adequate treatment of pain. [source] Cognitive functioning in substance abuse and dependence: a population-based study of young adultsADDICTION, Issue 9 2009Antti Latvala ABSTRACT Aims To investigate whether substance use disorders (SUDs) are associated with verbal intellectual ability, psychomotor processing speed, verbal and visual working memory, executive function and verbal learning in young adults, and to study the associations of SUD characteristics with cognitive performance. Participants A population-based sample (n = 466) of young Finnish adults aged 21,35 years. Measurements Diagnostic assessment was based on all available information from a structured psychiatric interview (SCID-I) and in- and out-patient medical records. Established neuropsychological tests were used in the cognitive assessment. Confounding factors included in the analyses were comorbid psychiatric disorders and risk factors for SUDs, representing behavioural and affective factors, parental factors, early initiation of substance use and education-related factors. Findings Adjusted for age and gender, life-time DSM-IV SUD was associated with poorer verbal intellectual ability, as measured with the Wechsler Adult Intelligence Scale,Revised (WAIS-R) vocabulary subtest, and slower psychomotor processing, as measured with the WAIS-R digit symbol subtest. Poorer verbal intellectual ability was accounted for by parental and own low basic education, whereas the association with slower psychomotor processing remained after adjustment for SUD risk factors. Poorer verbal intellectual ability was related to substance abuse rather than dependence. Other SUD characteristics were not associated with cognition. Conclusions Poorer verbal intellectual ability and less efficient psychomotor processing are associated with life-time alcohol and other substance use disorders in young adulthood. Poorer verbal intellectual ability seems to be related to parental and own low basic education, whereas slower psychomotor processing is associated with SUD independently of risk factors. [source] Guidelines for mechanical lung function measurements in psychophysiologyPSYCHOPHYSIOLOGY, Issue 5 2002Thomas Ritz Studies in psychophysiology and behavioral medicine have uncovered associations among psychological processes, behavior, and lung function. However, methodological issues specific to the measurement of mechanical lung function have rarely been discussed. This report presents an overview of the physiology, techniques, and experimental methods of mechanical lung function measurements relevant to this research context. Techniques to measure lung volumes, airflow, airway resistance, respiratory resistance, and airflow perception are introduced and discussed. Confounding factors such as ventilation, medication, environmental factors, physical activity, and instructional and experimenter effects are outlined, and issues specific to children and clinical groups are discussed. Recommendations are presented to increase the degree of standardization in the research application and publication of mechanical lung function measurements in psychophysiology. [source] Hereditary Breast Cancer: Part I. Diagnosing Hereditary Breast Cancer SyndromesTHE BREAST JOURNAL, Issue 1 2008Henry T. Lynch MD Abstract:, Hereditary breast cancer (HBC) accounts for as much as 10% of the total BC burden. Most of these cases will be found to be due to a BRCA germline mutation. An estimated additional 15,20% of those affected with BC will have one or more first- and/or second-degree relatives with BC. Therefore, when these numbers are combined, familial BC risk accounts for approximately 20,25% of the total BC burden. However, because of the often limited information on family history in the etiologic assessment of BC, this may be an underestimate. Confounding factors include its phenotypic and genotypic heterogeneity, given the association of HBC with a plethora of differing cancer syndromes. Its most common occurrence is its association with ovarian cancer in the so-called hereditary breast-ovarian cancer syndrome due to BRCA1 and BRCA2 mutations. More rarely, it occurs in the Li-Fraumeni syndrome, caused by a p53 germline mutation, in which markedly early-onset BC is found in association with brain tumors, sarcomas, leukemia, lymphoma, malignant melanoma, and adrenal cortical carcinoma. Importantly, the age-adjusted incidence of BC in women in the United States fell sharply, by 6.7%, in 2003, when compared with the rate identified in 2002. We postulate that increasing knowledge about the genetics of BC may have partially contributed to the identification of high-risk patients who thereby may have benefited significantly from early diagnosis. [source] Sphincter preservation in rectal cancer is associated with patients' socioeconomic statusBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 10 2010L. I. Olsson Background: Decision making regarding the choice of surgical procedure in rectal cancer is complex. It was hypothesized that, in addition to clinical factors, several aspects of patients' socioeconomic background influence this process. Methods: Individually attained data on civil status, education and income were linked to the Swedish Rectal Cancer Registry 1995,2005 (16 713 patients) and analysed by logistic regression. Results: Anterior resection (AR) was performed in 7433 patients (44·5 per cent), abdominoperineal resection (APR) in 3808 (22·8 per cent) and Hartmann's procedure in 1704 (10·2 per cent). Unmarried patients were least likely (odds ratio (OR) 0·76, 95 per cent confidence interval (c.i.) 0·64 to 0·88) and university-educated men were most likely (OR 1·30, 1·04 to 1·62) to have an AR. Patients with the highest income were more likely to undergo AR (OR 0·80, 0·85 and 0·86 respectively for first, second and third income quartiles). Socioeconomic differences in the use of AR were smallest among the youngest patients. Unmarried patients were more likely (OR 1·21, 95 per cent c.i. 1·00 to 1·48) and university-educated patients less likely (OR 0·78, 95 per cent c.i. 0·63 to 0·98) to have an APR. Conclusion: The choice of surgical strategy in rectal cancer is not socioeconomically neutral. Confounding factors, such as co-morbidity or smoking, may explain some of the differences but inequality in treatment is also plausible. Copyright © 2010 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. [source] Illusory and spurious correlations: distinct phenomena or joint outcomes of exemplar-based category learning?EUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 3 2006Thorsten Meiser Stereotype formation about novel groups was analyzed with trivariate stimulus distributions that were generated by group membership, valence of behavior, and a context variable. Within this stimulus setting, we manipulated the confounding role of the context variable and the distinctiveness of events in terms of their relative infrequency. The experimental procedure allowed us to analyze illusory and spurious correlations in a joint framework, to conduct focused tests for memory effects of relative infrequency and to investigate the detection of covariations with the context variable. The results revealed that illusory and spurious correlations were formed without enhanced memory for infrequent events and with existing covariations of the confounding context factor being well extracted. These observations suggest that illusory and spurious correlations can be understood without assuming specific cognitive processes that are tied to the particular characteristics of a given stimulus distribution, such as enhanced memory in the case of relative infrequency and neglect of a context variable in the case of a confounding factor. Instead, computer simulations with an exemplar-based learning model demonstrated that exemplar-based category learning may provide a coherent and integrative theoretical framework for illusory correlations, spurious correlations and true contingency learning in social cognition. Copyright © 2006 John Wiley & Sons, Ltd. [source] Proliferative activity and diagnostic delay in oral cancerHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 10 2010Juan Seoane PhD Abstract Background Tumor stage may relate to the chronology of neoplasm growth and has been used as an outcome variable when studying diagnostic delay in oral cancer. However, tumor growth rate may act as a confounding factor. Methods We reviewed a total of 63 incident cases of oral cancer. The variables considered for the study included age, sex, smoking history, tumor site, TNM stage, Ki-67 score, and diagnostic delay. Results Significant differences between survivors and exitus were found in terms of tumor stage at diagnosis (I,II vs III,IV), sex, and Ki-67 scores. When the analysis was adjusted for tumor stage at diagnosis (I,II vs III,IV), proliferative activity resulted to be an independent prognostic factor for survival, whereas diagnostic delay did not influence survival. Conclusion These results seem to suggest that survival from oral cancer is affected more by the biology of the cancer (rapid tumor growth) than by diagnostic delay. © 2010 Wiley Periodicals, Inc. Head Neck, 2010 [source] Back to the Future: Middle Molecules, High Flux Membranes, and Optimal DialysisHEMODIALYSIS INTERNATIONAL, Issue 1 2003Raymond C. Vanholder Middle molecules can be defined as compounds with a molecular weight (MW) above 500 Da. An even broader definition includes those molecules that do not cross the membranes of standard low-flux dialyzers, not only because of molecular weight, but also because of protein binding and/or multicompartmental behavior. Recently, several of these middle molecules have been linked to the increased tendency of uremic patients to develop inflammation, malnutrition, and atheromatosis. Other toxic actions can also be attributed to the middle molecules. In the present publication we will consider whether improved removal of middle molecules by large pore membranes has an impact on clinical conditions related to the uremic syndrome. The clinical benefits of large pore membranes are reduction of uremia-related amyloidosis; maintenance of residual renal function; and reduction of inflammation, malnutrition, anemia, dyslipidemia, and mortality. It is concluded that middle molecules play a role in uremic toxicity and especially in the processes related to inflammation, atherogenesis, and malnutrition. Their removal seems to be related to a better outcome, although better biocompatibility of membranes might be a confounding factor. [source] Endogenous testosterone levels and smoking in men.INTERNATIONAL JOURNAL OF ANDROLOGY, Issue 3 2007The fifth Tromsø study Summary Smoking is a risk factor of coronary heart disease (CHD), while the role of testosterone in the development of CHD is controversial. The reported effects of cigarette smoking on testosterone levels in men are conflicting, and smoking may be an important confounding factor when evaluating the relationship between testosterone levels and CHD. Thus, the objective of the present study was to examine the associations of smoking status and number of cigarettes smoked per day with total and free testosterone levels in a cross-sectional population-based study of 3427 men participating in the fifth Tromsø study. Total testosterone, luteinizing hormone, follicle-stimulating hormone and sex hormone-binding globulin levels were measured with immunoassay while free testosterone levels were calculated. Waist circumference was also measured and two standardized questionnaires were completed, including smoking status and number of cigarettes smoked. The data were analysed with analysis of variance and covariance and multiple regression analysis. Smoking men had significantly higher levels of total and free testosterone compared with men who never smoked (p < 0.001 and <0.01 respectively). Both total and free testosterone levels increased significantly with increasing number of cigarettes smoked daily (p < 0.001). Smoking men had 15% higher total and 13% higher free testosterone levels compared with men who never smoked. Thus, smoking seems to be an important confounding factor when evaluating testosterone levels, and could possibly mask borderline hypogonadism. [source] Generalized cervical root resorption associated with periodontal diseaseJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 11 2001Wouter Beertsen Abstract Background and description of case: The etiology and pathogenesis of generalized cervical root resorptions is not well understood. In the present report, a case of severe cervical root resorption involving 24 anterior and posterior teeth is presented. The lesions developed within a period of 2 years after the patient had changed to an acid-enriched diet. They extended far into the coronal dentin and were associated with gingival inflammation and crestal bone resorption. However, no generalized clinical attachment loss had occurred. Culturing of subgingival plaque revealed the presence of several putative periodontal pathogens among which Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis. Treatment consisted of mechanical debridement supported by systemic antibiotics (amoxycillin plus metronidazole) and dietary advice. Results: Within 1 year after the onset of treatment, all resorptive lesions had repaired by ingrowth of a radio-opaque mineralized tissue. The crestal areas showed radiological evidence of bone repair. 3 years after the onset of therapy, one premolar was extracted and examined histologically. It appeared that irregularly-shaped masses of woven bone-like tissue had invaded into the domain of the resorbed coronal dentin and were bordered by thin layers of acellular cementum. Conclusion: It is concluded that, in this patient, the cervical resorptions were likely the result of an osteoclastic response extending into the roots because the root-protective role of the junctional epithelium did not develop. We hypothesize that this was due to the combined effects of a periodontopathogenic microflora and a dietary confounding factor. Zusammenfassung Hintergrund und Beschreibung des Falls: Die Ätiologie und die Pathogenese der generalisierten Wurzelresorptionen ist nicht besonders bekannt. In der vorliegenden Fallpräsentation wird ein schwerer Fall von Wurzelresorption gezeigt, die 24 anteriore und posteriore Zähne einbezog. Die Läsionen entwickelten sich innerhalb einer Periode von 2 Jahren, nachdem der Patient zu einer Säure-angereicherten Diät gewechselt hatte. Die Läsionen dehnten sich in das koronale Dentin aus und waren mit gingivaler Entzündung und krestaler Knochenresorption verbunden. Jedoch wurde kein generalisierter Attachmentverlust beobachtet. Die Kultur der subgingivalen Plaque erbrachte das Vorhandensein von verschiedenen putativen parodontalen Pathogenen, unter ihnen Actinobacillus actinomycetemcomitans und Porphyromonas gingivalis. Die Behandlung bestand in der mechanischen Reinigung unterstützt mit systemischen Antibiotika (Amoxicillin und Metronidazol) und Diätanweisungen. Ergebnisse: Innerhalb eines Jahres nach dem Beginn der Therapie waren alle Resorptionsläsionen repariert durch das Einwachsen von röntgenopakem mineralisierten Gewebe. Die krestalen Regionen zeigten radiologisch nachgewiesene Knochenreparatur. 3 Jahre nach Therapiebeginn wurde ein Prämolar extrahiert und histologisch untersucht. Es schien, daß irreguläre geformte Massen von verflochtenem knochen-ähnlichen Gewebe in den Hauptteil des resorbierten koronalen Dentins hineingelangt sind und von dünnen Schichten azellulären Zementes begrenzt wurden. Zusammenfassung: Es wird geschlußfolgert, daß bei diesem Patient die zervikalen Resorptionen wahrscheinlich das Ergebnis einer osteoklastischen Reaktion waren, bis in die Wurzeln ausgedehnt, weil sich die wurzelschützende Rolle des Verbindungsepithels nich entwickelt hatte. Wir nehmen an, daß dies in der Folge eines kombinierten Effektes von parodontopathogenen Keimen und eines verwirrenden diätetischen Faktors geschah. Résumé Origine: L'étiologie et la pathogenèse des résorptions radiculaires cervicales généralisées ne sont pas suffisamment connues. Dans le rapport présent, un cas de résorption radiculaire cervicale sévère se rapportant à 24 dents antérieures et postérieures est présenté. Les lésions s'étaint développées durant les 2 années qui ont suivi le changement de régime alimentaire du patient vers un régime plus acide. Elles s'étendaient profondément dans la dentine coronaire et étaient associées à une inflammation gingivale et une résorption osseuse crestale. Cependant, aucune perte d'attache clinique généralisée n'est apparue. La culture de la plaque dentaire sous-gingivale a révélé la présence de plusieurs pathogènes parodontaux putatifs parmi lesquels l'Actinobaccilus actinomycetemcomitans et le Porphyromonas gingivalis. Le traitement a consisté en un nettoyage mécanique associéà l'utilisation d'antibiotiques par voie systémique (amoxycilline + métronidazole) et un conseil diététique. Résultats. Dans l'année qui a suivi ce traitement, toutes les lésions de résorption ont été guéries par la croissance d'un tissu minéralisé radio-opaque. Les zones crestales montraient une évidence radiologique de réparation osseuse. 3 ans après le démarrage de ce traitement, une prémolaire a été avulsée et examinée histologiquement. Il est apparu que des masses de formes irrégulières de tissus ressemblant à de l'os ouaté avaient envahi le domaine de dentine coronaire résorbé et étaient entourées par de fines couches de cément acellulaire. Conclusions: Chez ce patient, les résorptions cervicales étaient vraisemblablement dûes à une réponse ostéoclastique s'étendant dans les racines parce que le rôle de protection radiculaire de l'épithélium de jonction ne s'étaient pas développé. Cette situation était vraisemblablement dûe à des effets combinés de la microflore parodonto-pathogène et d'un facteur diététique. [source] Post-transfusion white cell count in the sick preterm neonateJOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 1 2001IMR Wright Objective: A previous report demonstrated post-transfusion leucocytosis as a potential confounding factor in the diagnosis of sepsis in critically ill adult patients. In We wished to establish if the same phenomenon occurred in the sick preterm neonate and whether this significantly altered the indices considered for potential neonatal infection. Methodology: Transfusion and full blood count data in a level 3 neonatal intensive care unit were prospectively recorded for 3 months. Results: One hundred and fourteen transfusion events were recorded from 37 infants. Median white blood cell count increased 0.9 × 109/L (confidence interval (CI) 0.4,2.4) in the first 8 h following transfusion (P = 0.032). Median neutrophil count increased by 0.4 × 109/L (CI 0.1,1.7) in the same 8 h (P = 0.05). Median neutrophil left shift decreased 1.2% (CI 1.1,5.8%) over the 24 h post-transfusion. No change in band count was observed. Conclusions: A mild post-transfusion white cell increase occurs in sick neonates. Because of the magnitude of effect, it is unlikely that this interesting physiological response would interfere with the diagnosis of sepsis in this population. [source] Naming speed and word familiarity as confounding factors in decodingJOURNAL OF RESEARCH IN READING, Issue 2 2002R. Malatesha Joshi The present investigation has three aims: (1) to establish a suitable composite index which combines speed and accuracy in the measurement of decoding skill; (2) to examine whether speed acts as a confounding factor in the measurement of decoding ability; and (3) to see whether familiarity with the word, as indicated by the ability to pronounce it, or lack of it acts as a confounding factor in the assessment of spelling skills. Three studies were conducted to fulfill these aims. In the first study, 33 children from Grade 2 were asked to name a list of 40 letters of the alphabet as quickly and as accurately as possible. A combined index of speed and accuracy was computed from these two sets of data using two formulas, which were based on the ,z' score and the mean variance score. A Pearson product-moment correlation coefficient of 0.94 was obtained between the results of the two formulas indicating that the two formulas yield almost identical results. In the second study, 37 fifth-graders were administered the word-attack sub-test of Woodcock Language Proficiency Battery. When the speed and accuracy composite index, based on the ,z formula' was applied to the word-attack scores, it was found that three children were slow decoders even though their scores were within the normal range. In the third study, 39 children from Grade 3 and 40 children from Grade 5 were asked to read aloud a list of words and then these words were administered as a spelling test. Subsequently, their spelling ability was assessed by computing the number of words they could both read and spell correctly. When familiarity of words was included as a factor in assessing spelling ability, five children in Grade 3 and three children in Grade 5 were found to be misclassified as poor spellers. This indicates that including word-naming speed and word familiarity (i.e. ability to pronounce) produce different metrics than when they are not. Inclusion of speed and familiarity factors in assessment can be helpful in avoiding false negatives and false positives. [source] Eosinophilic oesophagitis in adultsNEUROGASTROENTEROLOGY & MOTILITY, Issue 10 2009N. Gonsalves Abstract, Previously considered a rare condition, eosinophilic oesophagitis (EoE) has become increasingly recognized as an important cause of dysphagia and food impactions in adults. This is likely attributable to a combination of an increasing incidence of EoE and a growing awareness of the condition. EoE may occur in isolation or in conjunction with eosinophilic gastroenteritis. However, the burgeoning field is likely attributable to the variant that uniquely affects the oesophagus. Adults classically present with symptoms of dysphagia, food impactions, and heartburn. Typical endoscopic features include concentric mucosal rings, linear furrowing, white plaques or exudates and a narrow caliber oesophagus. In some cases, the endoscopic features may appear normal. For years, EoE went unrecognized because eosinophilic infiltration was accepted as a manifestation of reflux, which continues to be a confounding factor in some patients. Current consensus is that the diagnosis of EoE is established by 1) the presence of symptoms, especially dysphagia and food impactions in adults, 2) ,15 eosinophils per high power field in oesophageal tissue, and 3) exclusion of other disorders with similar presentations such as GERD. Current understanding of EoE pathophysiology and natural history are limited but the entity has been increasingly linked to food allergies and aeroallergens. The main treatment options for EoE are proton pump inhibitors, dietary manipulation, and topical or oral glucocorticoids. This review highlights recent insights into EoE in adults although, clearly, much of the available data overlap with pediatrics and, occasionally, with eosinophilic gastroenteritis. [source] Understanding Atrial Symptom Reports: Objective versus Subjective PredictorsPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 8 2005SAMUEL F. SEARS Background: Atrial fibrillation (AF) is the most common cardiac arrhythmia and is associated with a variety of symptoms such as dizziness, palpitations, shortness of breath, and other signs of heart failure, which in turn impact quality of life (QOL). Implantable cardioverter defibrillators with atrial therapies (ICDs-ATs) have been shown to reduce AF symptoms and improve QOL in select AF samples. Method: This study examined the strength of relationships between objective (device-detected AF events) versus subjective (emotional symptoms) data and AF symptoms (number) reported as part of the Patient Atrial Shock Survey of Acceptance and Tolerance Study (N = 96, 72% men, M age = 65, SD = 12). Depression and anxiety were assessed via the Center for Epidemiological Studies,Depression Scale and the-State Trait Anxiety Inventory. AF disease burden was measured via a number of device-detected AF episodes and the Atrial Tachyarrhythmia Symptom Severity Scale. Results: Hierarchical multiple regression analysis indicated that negative emotions accounted for a significant 13.2% of unique variance in AF symptom score (F change (1, 54) = 9.625, P = 0.003). On the other hand, the number of device-detected AF episodes accounted for non-significant 8.2% of unique variance in the AF symptom score (P = 0.167). The full model explained 25.7% of the variance in AF symptom score (F(6, 54) = 3.110, P = 0.011). Specifically, greater number of treated AF episodes (,= 0.251, P = 0.043) and higher levels of negative emotions (,= 0.369, P = 0.003) predicted greater number of reported AF symptoms. Conclusion: Therefore, psychological distress may be a significant confounding factor affecting patient's report of AF symptoms rather than the actual experience of recurrent AF episodes. [source] Comparison of EML 105 and Advantage analysers measuring capillary versus venous whole blood glucose in neonatesACTA PAEDIATRICA, Issue 9 2001PJ McNamara Aim: Near-patient blood glucose monitoring is an essential component of neonatal intensive care but the analysers currently used are unreliable and inaccurate. The aim of this study was to compare a new glucose electrode-based analyser (EML 105) and a non-wipe reflectance photometry method (Advantage) as opposed to a recognized laboratory reference method (Hexokinase). We also investigated the effect of sample route and haematocrit on the accuracy of the glucose readings obtained by each method of analysis. Methods: Whole blood glucose concentrations ranging from 0 to 3.5mmol/l were carefully prepared in a laboratory setting and blood samples from each respective solution were then measured by EML 105 and Advantage analysers. The results obtained were then compared with the corresponding plasma glucose reading obtained by the Hexokinase method, using linear regression analysis. An in vivo study was subsequently performed on 103 neonates, over a 1-y period, using capillary and venous whole blood samples. Whole blood glucose concentration was estimated from each sample using both analysers and compared with the corresponding plasma glucose concentration estimated by the Hexokinase method. Venous blood was centrifuged and haematocrit was estimated using standardized curves. The effect of haematocrit on the agreement between whole blood and plasma glucose was investigated, estimating the degree of correlation on a scatterplot of the results and linear regression analysis. Results: Both the EML 105 and Hexokinase methods were highly accurate, in vitro, with small proportional biases of 2% and 5%, respectively. However, in vivo, both study analysers overestimated neonatal plasma glucose, ranging from at best 0.45 mmol/l (EML 105 venous) to 0.69 mmol/l (EML capillary). There was no significant difference in the agreement of capillary (GD = 0.12, 95% CI. {-0.32,0.08}, p= 0.2) or venous samples (GD = 0.05, 95% CI. {0.09, 0.19}, p= 0.49) with plasma glucose when analysed by either study method (GD = glucose difference between study analyser and reference method) However, the venous samples analysed by EML 105 estimated plasma glucose significantly better than capillary samples using the same method of analysis (GD = 0.24, 95% CI. {0.09, 0.38}, p < 0.01). The relationship between haematocrit and the resultant glucose differences was non-linear with correlation coefficients of r= -0.057 (EML 105 capillary), r= 0.145 (EML 105 venous), r= -0.127 (Advantage capillary) and r= -0.275 (Advantage venous). There was no significant difference in the effect of haematocrit on the performance of EML 105 versus Advantage, regardless of the sample route. Conclusion: Both EML 105 and Advantage overestimated plasma glucose, with no significant difference in the performance of either analyser, regardless of the route of analysis. Agreement with plasma glucose was better for venous samples but this was only statistically significant when EML 105 capillary and venous results were compared. Haematocrit is not a significant confounding factor towards the performance of either EML 105 or Advantage in neonates, regardless of the route of sampling. The margin of overestimation of blood glucose prohibits the recommendation of both EML 105 and Advantage for routine neonatal glucose screening. The consequences include failure accurately to diagnose hypoglycaemia and delays in the instigation of therapeutic measures, both of which may potentially result in an adverse, long-term, neurodevelopmental outcome. [source] THE EFFECT OF COUNTY-LEVEL PRISON POPULATION GROWTH ON CRIME RATES,CRIMINOLOGY AND PUBLIC POLICY, Issue 2 2006TOMISLAV V. KOVANDZIC Research Summary: Prior macro-level studies examining the impact of prison population growth on crime rates have produced widely varying results. Studies using national-level time series data find large impacts of prison growth on crime, whereas those using state panel data find more modest ones. Critics of the former studies maintain that the estimates are implausibly large, arguing that the effects are instead due to analysts' inability to control for potential confounding factors. Conversely, critics of the latter studies argue that they underestimate the total impacts of imprisonment by failing to account for potential free-riding effects. This study uses panel data for 58 Florida counties for 1980 to 2000 to reexamine the link between prison population growth and crime. Unlike previous studies, we find no evidence that increases in prison population growth covary with decreases in crime rates. Policy Implications: Our findings suggest that Florida policymakers carefully weigh the costs and benefits of their continued reliance on mass incarceration against the potential costs and benefits of alternatives. If the costs of mass incarceration do not return appreciable benefits, i.e., a reduction in crime, it is time to reconsider our approach to crime and punishment. Other research offers evidence of crime prevention programs operating inside the criminal justice system and in communities that hold promise for reducing crime; our findings indicate that policymakers carefully consider these options as a way to achieve their goals. [source] Guidelines for improving the reproducibility of quantitative multiparameter immunofluorescence measurements by laser scanning cytometry on fixed cell suspensions from human solid tumorsCYTOMETRY, Issue 1 2006Stanley Shackney Abstract Background: Laser scanning Cytometry (LSC) is a versatile technology that makes it possible to perform multiple measurements on individual cells and correlate them cell by cell with other cellular features. It would be highly desirable to be able to perform reproducible, quantitative, correlated cell-based immunofluorescence studies on individual cells from human solid tumors. However, such studies can be challenging because of the presence of large numbers of cell aggregates and other confounding factors. Techniques have been developed to deal with cell aggregates in data sets collected by LSC. Experience has also been gained in addressing other key technical and methodological issues that can affect the reproducibility of such cell-based immunofluorescence measurements. Methods and results: We describe practical aspects of cell sample collection, cell fixation and staining, protocols for performing multiparameter immunofluorescence measurements by LSC, use of controls and reference samples, and approaches to data analysis that we have found useful in improving the accuracy and reproducibility of LSC data obtained in human tumor samples. We provide examples of the potential advantages of LSC in examining quantitative aspects of cell-based analysis. Improvements in the quality of cell-based multiparameter immunofluorescence measurements make it possible to extract useful information from relatively small numbers of cells. This, in turn, permits the performance of multiple multicolor panels on each tumor sample. With links among the different panels that are provided by overlapping measurements, it is possible to develop increasingly more extensive profiles of intracellular expression of multiple proteins in clinical samples of human solid tumors. Examples of such linked panels of measurements are provided. Conclusions: Advances in methodology can improve cell-based multiparameter immunofluorescence measurements on cell suspensions from human solid tumors by LSC for use in prognostic and predictive clinical applications. © 2005 Wiley-Liss, Inc. [source] Prognostic impact of psychoactive substances use during hospitalization for intentional drug overdoseACTA PSYCHIATRICA SCANDINAVICA, Issue 2 2005M. Tournier Objective:, To assess whether current use of psychoactive substance(s) is a prognostic factor during hospitalization for intentional drug overdose (IDO). Method:, Current intoxication with psychoactive substance(s) [cannabis, opiate, buprenorphine, amphetamine/ecstasy, cocaine, lysergic acid diethylamide (LSD)] was identified using toxicological urinalysis in 671 patients with IDO. An IDO was a priori defined as serious if associated with one of the following events: death, hospitalization in intensive care unit longer than 48 h, respiratory support, use of vasopressive drugs, cardiac massage or dialysis. Results:, Subjects positive for toxicological assays were twice as likely to present with serious IDO (OR = 1.9, 95% CI: 1.3,2.8, P = 0.001), independently from a large range of confounding factors. The risk of serious IDO was especially marked in subjects using LSD, buprenorphine or opiates. Conclusion:, Systematic investigation of substance use could be important to adapt medical management of subjects with IDO in general hospital, but also in primary care and psychiatric settings. [source] Association of the metabolic syndrome with depression and anxiety in Japanese men: A 1-year cohort studyDIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue 8 2009Takeaki Takeuchi Abstract Background Recent studies on the association between the metabolic syndrome (MetS) and depression have reported conflicting findings. This 1-year cohort study aims to evaluate the association of MetS with the development of both depression and anxiety. Methods The cohort comprised 956 Japanese male employees of an enterprise (mean age, 42.7 years; SD, 10.2 years). MetS was diagnosed according to the International Diabetes Federation criteria. The psychological conditions of depression and anxiety were assessed in 2 successive years by using the profile of mood states (POMS) questionnaire and by conducting clinical interviews as per the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV). We evaluated the temporal and dose-response relationships between MetS and the development of depression and anxiety, controlling for potential confounding factors like age and lifestyle-related factors. Results We identified a positive relationship between MetS at baseline and new-onset depression in the subsequent year (OR 2.14, 95% CI 1.10,4.17). Of the five MetS components examined, only waist circumference was significantly related to new-onset depression (OR 2.08, 1.23,3.50). Trend analysis revealed a significant positive trend of association between the number of MetS components identified and new-onset depression (Ptrend < 0.01), but not between Mets and new-onset anxiety. Conclusions Our results suggest that MetS is a predictive factor for the development of depression, and that waist circumference largely contributes to the association between MetS and depression. Copyright © 2009 John Wiley & Sons, Ltd. [source] Interactive effect of central obesity and hypertension on cognitive function in older out-patients with Type 2 diabetesDIABETIC MEDICINE, Issue 12 2008E. Kim Abstract Aim Central obesity, hypertension and diabetes mellitus have been related individually to cognitive dysfunction. We aimed to study the interactive effects of these co-occurring risk factors on cognitive decline, which remain unclear in older patients with diabetes. Methods We assessed metabolic profiles and neuropsychological functions in 60 older out-patients with Type 2 diabetes to examine the associations of central obesity with cognitive functions, while controlling for other confounding factors in these subjects. Results Waist circumference was associated with poor performance in digits forward (r2 = 0.11, P = 0.02), choice reaction time (r2 = 0.08, P = 0.04) and cognitive reaction time (r2 = 0.07, P < 0.05) even after adjustment for potential confounders including age, gender, education and HbA1c. There were also significant interactions between central obesity and hypertension with respect to performance of digits forward (P = 0.04) and delayed verbal cued recall (P = 0.03). Conclusion Our findings suggest that, in addition to glycaemic control, central obesity and hypertension influence cognitive functions, such as attention and psychomotor speed in older patients with Type 2 diabetes. [source] Glycaemic control in relation to xanthine oxidase and antioxidant indices in Malaysian Type 2 diabetes patientsDIABETIC MEDICINE, Issue 10 2005U. R. Kuppusamy Abstract Aims Increased oxidative stress and oxidative damage are present in Type 2 diabetes mellitus (DM). The aim of this study was to assess the oxidative stress levels in the three major ethnic groups in Malaysia and to study the association between glycaemic control and oxidant,antioxidant levels in these patients. Methods Oxidative indices and glycaemic control were assessed in 650 Type 2 DM patients and 280 healthy age-matched controls by known established methods. Results Type 2 DM patients had significantly lower levels of antioxidant enzymes and non-enzymatic antioxidant (FRAP) and increased levels of HbA1c, fasting blood glucose (FBG), malondialdehyde (MDA) and xanthine oxidase (XO) when compared with control subjects. Markers of oxidative stress were more apparent in Indian patients compared with Malay and Chinese patients. Correlation analysis of oxidant,antioxidant parameters as a function of HbA1c in each ethnic group revealed a strong association of HbA1c with oxidative indices. Conclusions The present study provides evidence for the possible contribution of XO to oxidative stress and the pathophysiology of diabetes. HbA1c remains an important marker of glycaemic control for the management of Type 2 DM, but other confounding factors that predispose or lead to oxidative stress should also be taken into consideration. [source] MDMA, methamphetamine and their combination: possible lessons for party drug users from recent preclinical researchDRUG AND ALCOHOL REVIEW, Issue 1 2007KELLY J. CLEMENS Abstract The substituted amphetamines 3,4-methylenedioxymethamphetamine (MDMA, ,Ecstasy') and methamphetamine (METH, ,ice', ,speed') are increasingly popular drugs amongst party-drug users. Studies with humans have investigated the acute and possible long-term adverse effects of these drugs, yet outcomes of such studies are often ambiguous due to a variety of confounding factors. Studies employing animal models have value in determining the acute and long-term effects of MDMA and METH on brain and behaviour. Self-administration studies show that intravenous METH is a particularly potent reinforcer in rats and other species. In contrast, MDMA appears to have powerful effects in enhancing social behaviour in laboratory animals. Brief exposure to MDMA or METH may produce long-term reductions in dopamine, serotonin and noradrenaline in the brain and alterations in the density of various receptor and transporter proteins. However it is still unclear, particularly in the case of MDMA, whether this reflects a ,neurotoxic' effect of the drug. Lasting alterations in social behaviour, anxiety, depressive symptoms and memory have been demonstrated in laboratory rats given MDMA or METH and this matches long-term changes reported in some human studies. Recent laboratory studies suggest that MDMA/METH combinations may produce greater adverse neurochemical and behavioural effects than either drug alone. This is of some concern given recent evidence that party drug users may be frequently exposed to this combination of drugs. [source] Effects of Continuous Positive Airway Pressure Therapy on Right Ventricular Function Assessment by Tissue Doppler Imaging in Patients with Obstructive Sleep Apnea SyndromeECHOCARDIOGRAPHY, Issue 10 2008Nihal Akar Bayram M.D. Objectives: The effects of continuous positive airway pressure (CPAP) therapy on right ventricular (RV) function in patients with obstructive sleep apnea syndrome (OSAS) has not been previously studied by tissue Doppler imaging (TDI). The aim of this study was to assess RV function using TDI in patients with OSAS before and after CPAP therapy. Methods: Twenty-eight patients with newly diagnosed OSAS in the absence of any confounding factors and 18 controls were included in this study. The peak systolic velocity (S,m), early (E,m) and late (A,m) diastolic myocardial peak velocities at tricuspid lateral annulus, isovolumic acceleration (IVA), myocardial precontraction time (PCT,m), myocardial contraction time (CT,m), and myocardial relaxation time (RT,m) were measured. All echocardiographic parameters were calculated 6 months after CPAP therapy. Results: The RV diastolic parameters such as E,m velocity and E,m-to-A,m ratio were significantly lower, RT,m was significantly prolonged, A,m velocity was similar in patients with OSAS compared to controls; and the RV systolic parameters such as IVA and CT,m were significantly lower and S,m was similar in patients with OSAS compared to controls. At the end of the treatment, 20 of 28 patients were compliant with CPAP therapy. E,m velocity, E,m-to-A,m ratio, IVA, and CT,m increased, PCT,m, PCT,m-to-CT,m ratio, and RT,m decreased significantly after therapy, whereas S,m velocity and A,m velocity did not change after CPAP treatment in the compliant patients. Conclusion: OSAS is associated with RV systolic and diastolic dysfunction, and 6 months of CPAP therapy improves the RV systolic and diastolic dysfunction. [source] Association of adolescent symptoms of depression and anxiety with daily smoking and nicotine dependence in young adulthood: findings from a 10-year longitudinal studyADDICTION, Issue 9 2010Maria McKenzie ABSTRACT Aims To examine the association of adolescent depression and anxiety symptoms with daily smoking and nicotine dependence in young adulthood. Design A prospective cohort study of adolescent and young adult health (n = 1943). Teen assessments occurred at 6-monthly intervals, with two follow-up assessments in young adulthood (wave 7, 1998; wave 8, 2001,03). Setting Victoria, Australia. Participants Students who participated at least once during the first six (adolescent) waves of the cohort study. Measurements Adolescent depression and anxiety symptoms were assessed using the Revised Clinical Interview Schedule (CIS-R). Young adult tobacco use was defined as: daily use (6 or 7 days per week) and dependent use (,4 on the Fagerstrom Test for Nicotine Dependence). Findings Among adolescent ,less than daily' smokers, those with high levels of depression and anxiety symptoms had an increased risk of reporting nicotine dependence in young adulthood [odds ratio (OR) 3.3, 95% confidence interval (CI) 1.2,9.1] compared to young adults who had low levels of adolescent depression and anxiety symptoms, after adjusting for potential confounding factors. Similarly, in the adjusted model (OR 1.9, 95% CI 1.0,3.4), among adolescent ,daily' smokers, those with high levels of depression and anxiety symptoms had an almost two-fold increase in the odds of reporting nicotine dependence in young adulthood compared to young adults with low levels of adolescent depression and anxiety symptoms. Conclusions Adolescent smokers with depression and anxiety symptoms are at increased risk for nicotine dependence into young adulthood. They warrant vigilance from primary care providers in relation to tobacco use well into adulthood. [source] The effect of stopping smoking on perceived stress levelsADDICTION, Issue 8 2010Peter Hajek ABSTRACT Aims Many smokers believe that smoking helps them to cope with stress, and that stopping smoking would deprive them of an effective stress management tool. Changes in stress levels following long-term smoking cessation are not well mapped. This longitudinal project was designed to provide more robust data on post-cessation changes in perceived stress levels by following a cohort of smokers admitted to hospital after myocardial infarction (MI) or for coronary artery bypass (CAB) surgery, as such patients typically achieve higher continuous abstinence rates than other comparable samples. Design A total of 469 smokers hospitalized after MI or CAB surgery and wanting to stop smoking were seen in the hospital and completed 1-year follow-ups. Ratings of helpfulness of smoking in managing stress at baseline, smoking status (validated by salivary cotinine concentration) and ratings of perceived stress at baseline and at 1-year follow-up were collected. Findings Of the patients, 41% (n = 194) maintained abstinence for 1 year. Future abstainers and future smokers did not differ in baseline stress levels or in their perception of coping properties of smoking. However, abstainers recorded a significantly larger decrease in perceived stress than continuing smokers, and the result held when possible confounding factors were controlled for (P < 0.001). Conclusions In highly dependent smokers who report that smoking helps them cope with stress, smoking cessation is associated with lowering of stress. Whatever immediate effects smoking may have on perceived stress, overall it may generate or aggravate negative emotional states. The results provide reassurance to smokers worried that stopping smoking may deprive them of a valuable coping resource. [source] Invasion success: does size really matter?ECOLOGY LETTERS, Issue 2 2002A. W. Miller The recent paper by Roy et al. (2001) presents a compelling relationship between range limit shifts, climatic fluctuations, and body size for marine bivalves in the fossil record. However, their extension of body size as a correlate for contemporary marine bivalve introductions is problematic and requires further scrutiny. Unlike their analysis of the fossil assemblage, the approach used for contemporary invasions does not adequately control for dispersal mechanism (vector) or source region. First, their analysis included mariculture species, intentionally introduced because of their large size, creating a vector-specific bias. Second, successful invaders from multiple source regions (Northern Hemisphere) were compared with potential invaders from a single source region (north-eastern Pacific), leaving both source and vector as uncontrolled variables. We present an analysis of body size for bivalve introductions from a single vector and source region, indicating no correlation between body size and invasion success when eliminating intentional introduction, source region and transport vector as confounding factors. [source] Evidence of a complex association between dose, pattern and timing of prenatal alcohol exposure and child behaviour problemsADDICTION, Issue 1 2010Colleen M. O'Leary ABSTRACT Background There is a lack of evidence regarding the effect of dose, pattern and timing of prenatal alcohol exposure and behaviour problems in children aged 2 years and older. Methods A 10% random sample of women delivering a live infant in Western Australia (1995,96) were invited to participate in an 8-year longitudinal survey (78% response rate n = 2224); 85% were followed-up at 2 years, 73% at 5 years and 61% at 8 years. Alcohol consumption was classified by combining the overall dose, dose per occasion and frequency to reflect realistic drinking patterns. Longitudinal analysis was conducted using generalized estimating equations (GEE) to investigate the association between child behaviour as measured by the Child Behaviour Checklist at 2, 5 and 8 years of age and prenatal alcohol exposure collected 3 months postpartum for each trimester separately, adjusting for a wide range of confounding factors. Results Low levels of prenatal alcohol were not associated with child behaviour problems. There were increased odds of internalizing behaviour problems following heavy alcohol exposure in the first trimester; anxiety/depression [adjusted odds ratio (aOR) 2.82; 95% confidence interval (CI) 1.07,7.43] and somatic complaints (aOR 2.74; 95% CI 1.47,5.12) and moderate levels of alcohol exposure increased the odds of anxiety/depression (aOR 2.24; 95% CI 1.16,4.34). Conclusions Prenatal alcohol exposure at moderate and higher levels increased the odds of child behaviour problems with the dose, pattern and timing of exposure affecting the type of behaviour problems expressed. Larger studies with more power are needed to confirm these findings. [source] Cannabis and crime: findings from a longitudinal studyADDICTION, Issue 1 2010Willy Pedersen ABSTRACT Aim To examine the association between cannabis use during adolescence and young adulthood, and subsequent criminal charges. Methods Data were obtained from the Young in Norway Longitudinal Study. A population-based sample (n = 1353) was followed from 13 to 27 years of age. Data were gathered on cannabis use, alcohol consumption and alcohol problems, and use of other illegal substances such as amphetamines, cocaine and opiates. In addition, extensive information on socio-demographic, family and personal factors was collected. This data set was linked to individual-level information from official Norwegian crime statistics. Findings We found robust associations between cannabis use and later registered criminal charges, both in adolescence and in young adulthood. These associations were adjusted for a range of confounding factors, such as family socio-economic background, parental support and monitoring, educational achievement and career, previous criminal charges, conduct problems and history of cohabitation and marriage. In separate models, we controlled for alcohol measures and for use of other illegal substances. After adjustment, we still found strong associations between cannabis use and later criminal charges. However, when eliminating all types of drug-specific charges from our models, we no longer observed any significant association with cannabis use. Conclusions The study suggests that cannabis use in adolescence and early adulthood may be associated with subsequent involvement in criminal activity. However, the bulk of this involvement seems to be related to various types of drug-specific crime. Thus, the association seems to rest on the fact that use, possession and distribution of drugs such as cannabis is illegal. The study strengthens concerns about the laws relating to the use, possession and distribution of cannabis. [source] DNA damage in Pakistani pesticide-manufacturing workers assayed using the Comet assayENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 8 2006Javed A. Bhalli Abstract The production and use of chemical pesticides has increased in recent years. Although the increased use of pesticides may benefit agriculture, they are also the potential source of environmental pollution, and exposure to pesticides can have negative consequences for human health. In the present study, we have assessed DNA damage in blood leukocytes from 29 Pakistani pesticide-factory workers and 35 controls of similar age and smoking history. The workers were exposed to various mixtures of organophosphates, carbamates, and pyrethroids. DNA damage was measured with the single cell gel electrophoresis (SCGE) assay or Comet assay, using the mean comet tail length (,m) as the DNA damage metric. Exposed workers had significantly longer comet tail lengths than the controls (mean ± SD 19.98 ± 2.87 vs. 7.38 ± 1.48, P < 0.001). Of the possible confounding factors, smokers had significantly longer mean comet tail lengths than nonsmokers and exsmokers for both the workers (21.48 ± 2.58 vs.18.37 ± 2.28, P < 0.001) and the controls (8.86 ± 0.56 vs. 6.79 ± 1.31, P < 0.001), while age had a minimal effect on DNA damage (P > 0.05 and P < 0.05 for workers and controls, respectively). The results of this study indicate that occupational exposure to pesticides causes DNA damage. Environ. Mol. Mutagen., 2006. © 2006 Wiley-Liss, Inc. [source] Smoking, nicotine dependence and mental health among young adults: a 13-year population-based longitudinal studyADDICTION, Issue 1 2009Willy Pedersen ABSTRACT Aims To investigate prospectively the associations between daily smoking and nicotine dependence and anxiety, depression and suicide attempts. Methods Data were from the Young in Norway Longitudinal Study. A population-based sample (n = 1501) was followed for 13 years from ages 13,27 years. Data were gathered on smoking patterns and nicotine dependence; and depression, anxiety and parasuicide. Extensive information on socio-demographic factors, parental and family conditions, parental rearing practices, educational career, conduct problems, alcohol problems and use of illegal substances was also collected. Results Young adults who were nicotine-dependent had clearly elevated rates of anxiety, depression and parasuicide. These rates declined after controlling for a previous history of mental health problems and potential confounding factors. After adjustment, nicotine dependence was still associated with anxiety, depression and parasuicide. There was also a significant association with later depression in the group of non-dependent daily smokers. Measures of reduced mental health did not predict later smoking initiation or the development of nicotine dependence. Conclusions Mental health was reduced more seriously in nicotine-dependent smokers than in non-dependent smokers. These findings are consistent with the hypothesis that smoking, in particular nicotine dependence, influences mental health. [source] | |||||||||||||||||||||||||||||||||||||