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PubMed1997

Family strengths, motivation, and resources as predictors of health promotion behavior in single-parent and two-parent families.

The extent to which selected aspects of family health potential (strengths, motivation, and resources) predicted health work (health-related problem-solving and goal attainment behaviors) was examined in a Canadian sample of 138 female-headed single-parent families and two-parent families. The mother and one child (age 10-14) each completed mailed self-report instruments to assess the independent variables of family cohesion, family pride, mother's non-traditional sex role orientation, general self-efficacy, internal health locus of control, network support, community support, and family income, as well as the dependent variable, health work. With the effects of mothers' education held constant, the independent variables predicted 22 to 27% of the variance in health work in the total sample and each family type. Family cohesion was the most consistent predictor of health work, accounting for 8 to 13% of the variance. The findings challenge existing problem-oriented views of single-parent families by focusing on their potential to engage in health promotion behavior.

Adolescent↗
PubMed1993

Predictors of psychosocial adjustment in systemic sclerosis. The influence of formal education level, functional ability, hardiness, uncertainty, and social support.

OBJECTIVE: To determine predictors of psychosocial adjustment in patients with systemic sclerosis (SSc). METHODS: We surveyed 94 patients with SSc. Age, sex, education level, marital status, work status, income, support group attendance, length of time since diagnosis, functional status, social support, illness-related uncertainty, and hardiness were examined as potential predictors of psychosocial adjustment. The reliability and validity of the instruments used to measure these variables have been established. RESULTS: Only education level, functional ability, illness-related uncertainty, hardiness, and social support were predictive of psychosocial adjustment. Education level and functional ability explained 14% of the variance in psychosocial adjustment, while illness-related uncertainty, hardiness, and social support increased the explained variance to 38%. CONCLUSION: Although patients with relatively poorer psychosocial adjustment to illness have lower formal education levels and more functional disability, the majority of the explained variance in psychosocial adjustment is ascribable to illness-related uncertainty, low level of hardiness, and less satisfaction with social support.

Adaptation, Psychological↗
PubMed1997

Perceived physical and emotional trauma as precipitating events in fibromyalgia. Associations with health care seeking and disability status but not pain severity.

OBJECTIVE: We examined relationships between perceived physical and emotional trauma that occur prior to, or that initiate, pain onset and health care seeking for fibromyalgia syndrome (FMS). We also assessed associations between perceived trauma and levels of health care usage, symptom severity, functional disability, and receipt of disability compensation among patients with FMS. METHODS: We evaluated these variables using interviews and standardized instruments in a consecutive series of FMS patients and community residents who met the American College of Rheumatology criteria for FMS but had not sought medical care ("nonpatients"). RESULTS: Emotional trauma was associated with status as an FMS patient independently of demographics, physical trauma, and sexual/physical abuse (P = 0.007). Among patients, emotional trauma was related to a high number of physician visits (P = 0.013), functional disability ratings (P = 0.012), and fatigue (P = 0.029), but physical trauma was associated with receipt of disability compensation (P = 0.019). Trauma history was not related to pain severity or pain thresholds. CONCLUSION: Perception of physical trauma is a greater determinant of disability compensation for FMS than is perceived emotional trauma, symptom severity, or functional disability. Effort should be devoted to understanding the social and legal factors underlying this observation, as well as to reducing high health care usage among FMS patients with emotional trauma.

Adolescent↗
PubMed1998

In situ calibration of miniature sensors implanted into the anterior cruciate ligament part I: strain measurements.

The goals of this study were to (a) evaluate the differential variable reluctance transducer as an instrument for measuring tissue strain in the anteromedial band of the anterior cruciate ligament, (b) develop a series of calibration curves (for simple states of knee loading) from which resultant force in the ligament could be estimated from measured strain levels in the anteromedial band of the ligament, and (c) study the effects of knee flexion angle and mode of applied loading on output from the transducer. Thirteen fresh-frozen cadaveric knee specimens underwent mechanical isolation of a bone cap containing the tibial insertion of the anterior cruciate ligament and attachment of a load cell to measure resultant force in the ligament. The transducer (with barbed prongs) was inserted into the anteromedial band of the anterior cruciate ligament to record local elongation of the instrumented fibers as resultant force was generated in the ligament. A series of calibration curves (anteromedial bundle strain versus resultant force in the anterior cruciate ligament) were determined at selected knee flexion angles as external loads were applied to the knee. During passive knee extension, strain readings did not always follow the pattern of resultant force in the ligament; erratic strain readings were often measured beyond 20 degrees of flexion, where the anteromedial band was slack. For anterior tibial loading, the anteromedial band was a more active contributor to resultant ligament force beyond 45 degrees of flexion and was less active near full extension; mean resultant forces in the range of 150-200 N produced strain levels on the order of 3-4%. The anteromedial band was also active during application of internal tibial torque; mean resultant forces on the order of 180-220 N produced strains on the order of 2%. Resultant forces generated by varus moment were relatively low, and the anteromedial band was not always strained. Mean coefficients of variation for resultant force in the ligament (five repeated measurements) ranged between 0.038 and 0.111. Mean coefficients of variation for five repeated placements of the strain transducer in the same site ranged from 0.209 to 0.342. Insertion and removal of this transducer at the anteromedial band produced observable damage to the ligament. In our study, repeatable measurements were possible only if both prongs of the transducer were sutured to the ligament fibers.

Aged↗
PubMedDate not supplied

Practical implications of some recent studies in electrospray ionization fundamentals.

In accomplishing successful electrospray ionization analyses, it is imperative to have an understanding of the effects of variables such as analyte structure, instrumental parameters, and solution composition. Here, we review some fundamental studies of the ESI process that are relevant to these issues. We discuss how analyte chargeability and surface activity are related to ESI response, and how accessible parameters such as nonpolar surface area and reversed phase HPLC retention time can be used to predict relative ESI response. Also presented is a description of how derivitizing agents can be used to maximize or enable ESI response by improving the chargeability or hydrophobicity of ESI analytes. Limiting factors in the ESI calibration curve are discussed. At high concentrations, these factors include droplet surface area and excess charge concentration, whereas at low concentrations ion transmission becomes an issue, and chemical interference can also be limiting. Stable and reproducible non-pneumatic ESI operation depends on the ability to balance a number of parameters, including applied voltage and solution surface tension, flow rate, and conductivity. We discuss how changing these parameters can shift the mode of ESI operation from stable to unstable, and how current-voltage curves can be used to characterize the mode of ESI operation. Finally, the characteristics of the ideal ESI solvent, including surface tension and conductivity requirements, are discussed. Analysis in the positive ion mode can be accomplished with acidified methanol/water solutions, but negative ion mode analysis necessitates special constituents that suppress corona discharge and facilitate the production of stable negative ions.

Solvents↗
PubMed1986

The development of normal and autistic children: a comparative study.

This study tests the hypothesis that the development of normal and autistic children differs only in rate and asymptote. A total of 195 normal children between 1 and 5 years of age, 160 normal children between 3 months and 24 months of age, and 41 autistic children between 5 and 11 years of age were evaluated on the eight psychological variables constituting the Behavioral Rating Instrument for Autistic and other Atypical Children (BRIAAC). While many similarities were found, there were a sufficient number of differences to justify DMS-III's statement that certain autistic behaviors are not normal at any stage of development. Differences were particularly prominent when the development of normal infants was compared with that of severely disturbed autistic children. In general, the issue of whether deviant development differs only quantitatively from normal development can best be decided on the basis of developmental data and by utilizing instruments that sample all the major characteristics of both populations.

Age Factors↗
PubMed2001

Point of care and central laboratory determinations of the aPTT are not interchangeable in surgical intensive care patients.

PURPOSE: The objective of the study was to compare a bedside whole blood activated partial thromboplastin time (aPTT) performed by a point of care (POC) apparatus (CoaguCheck(R) Pro) in surgical intensive care (SIC) patients with a conventional aPTT obtained from the central laboratory. METHODS: The prospective concomitant measurements of the two aPTT were performed in 233 samples from 46 consecutive patients admitted after cardiovascular or major abdominal surgery. RESULTS: Inter-operator, inter-instrument and inter-cartridge variability of the new device measured in three healthy volunteers and in nine patients in stable condition (controls) was low (F test: P=0.86). The agreement by Bland and Altman between POC and central laboratory aPTT (-20.2 +/- 18.8 sec) was not satisfactory. The agreement between POC and central laboratory aPTT in patients after surgery was worst (-17 +/- 33.1 sec). Heparin treatment or timing of blood sampling after intensive care admission (<48 hr vs >48 hr) did not influence the agreement. The correlation between POC or central laboratory aPTT and anti-factor Xa activity was poor (r(2) 0.077 and 0.181 respectively). The test which correlated the best to heparin doses was anti-factor Xa activity (r(2) 0.714). CONCLUSION: POC aPTT and central laboratory aPTT showed a poor agreement in SIC patients admitted after surgery, although in healthy volunteers or in control patients, this agreement was better. The best test to monitor heparin treatment in this setting was anti-factor Xa activity.

Abdomen↗
PubMed2003

Reliability and validity of the Biodex system 3 pro isokinetic dynamometer velocity, torque and position measurements.

This study quantitatively assessed the mechanical reliability and validity of position, torque and velocity measurements of the Biodex System 3 isokinetic dynamometer. Trial-to-trial and day-to-day reliability were assessed during three trials on two separate days. To assess instrument validity, measurement of each variable using the Biodex System 3 dynamometer was compared to a criterion measure of position, torque and velocity. Position was assessed at 5 degrees increments across the available range of motion of the dynamometer. Torque measures were assessed isometrically by hanging six different calibrated weights from the lever arm. Velocity was assessed (30 degrees/s to 500 degrees/s) across a 70 degrees arc of motion by manually accelerating the weighted lever arm. With the exception of a systematic decrease in velocity at speeds of 300 degrees/s and higher, the Biodex System 3 performed with acceptable mechanical reliability and validity on all variables tested.

Humans↗
PubMed2004

Effects of brief pain education on hospitalized cancer patients with moderate to severe pain.

The purpose of this randomized controlled study was to assess the effects of a structured pain education program on the pain experience of hospitalized cancer patients. Eligible cancer pain patients were randomly assigned to either an experimental group (receiving pain education 10-15 min per day for 5 days, n = 15) or a standard care control group (n = 15). The effects of the intervention on six pain-related variables were evaluated using three instruments. Pain intensity, pain interference with daily life, negative beliefs about opioids, beliefs about endurance of pain, pain catastrophizing (an individual's tendency to focus on and exaggerate the threat value of painful stimuli and negatively evaluate his or her own ability to deal with pain), and sense of control over pain were evaluated by the Brief Pain Inventory-Short Form Taiwanese version (BPI-T), Pain and Opioid Analgesic Beliefs Scale-Cancer (POABS-CA), and the Catastrophizing subscale and the sense of control over pain measure from the Coping Strategies Questionnaire (CSQ). The results indicated that, after completing treatment, patients who had received structured pain education had significantly less pain intensity on average, negative pain beliefs regarding opioids, pain endurance beliefs, and pain catastrophizing than patients in the control group. In addition, patients in the pain education group showed a significant increase in their sense of control over pain. These preliminary results strongly suggest that structured pain education can effectively improve the pain experience of hospitalized cancer patients and should be further implemented clinically.

Attitude to Health↗
PubMed2004

Efficacy of budipine and placebo in untreated patients with Parkinson's disease.

Previous studies demonstrated the efficacy of budipine on motor symptoms of treated patients with Parkinson's disease (PD) with rating scales. However rating procedures may be subjective and variable. Therefore additional use of instrumental motor tests are helpful to reflect therapeutic benefits. Objective was to test the efficacy of 20 mg budipine (t.i.d.) in 51 previously untreated idiopathic PD patients in a monocenter, double-blind, placebo-controlled trial with a 2:1 randomisation over a three month interval. Budipine was not superior to placebo application. However a detailed analysis of rating results shows, that budipine but not placebo treated patients significantly improved. Budipine caused significant better outcomes of motor tests with execution of complex movements, but did not change results of tasks, which demand for simple motions. Placebo significantly improved dopamine sensitive motor test results. These outcomes may result from improved non dopaminergic neurotransmission due to budipine. Placebo caused better results of dopamine sensitive tests, since placebo may release endogenous dopamine.

Adult↗
PubMed2005

Correlates of reflective practice in medicine.

BACKGROUND: The ability of physicians to critically reflect on their professional practice has been increasingly valued. Previous research brought to light the multidimensional structure of reflective practice in medicine. It comprises at least five sets of behaviours in response to complex medical problems encountered in professional practice. Factors associated to reflective practice among physicians have, as far as we know, not yet been explored by empirical study. PURPOSE: To study factors correlated to reflective practice among physicians. METHODS: A questionnaire exploring characteristics of professional practice and educational experiences was administered to primary health care physicians. Measurements were related to scores on a reflective practice measuring instrument developed previously. Associations between variables were examined by statistical analysis with tests of correlation and analysis of variance. RESULTS: Reflective practice is negatively correlated to physician's age and number of years of clinical practice. Working mainly in hospitals and attendance to medical residency programmes in some specialties apparently have a positive effect on reflective practice. CONCLUSION: Reflective practice tends to decrease with experience. Findings are consistent with the literature on medical expertise that shows a decline of analytical reasoning in proportion to the increase in experience. Some specialty programmes seems to enhance concerns with the scientific basis to professional practice, thereby favouring reflective approaches. Local features of primary health care settings probably explain their negative effect on reflective practice. Strategies to develop reflective practice among physicians should be explored by further research.

Adult↗
PubMed1989

Precision and accuracy of absolute lymphocyte counts.

A critique of leukocyte counting using automated hematology instruments is presented. Important preanalytical variables include the anticoagulant and specimen assay delays. The precision of counts is directly related to the number of leukocytes counted. Criteria for the selection of an acceptable hematology laboratory for lymphocyte counts for CD4 determinations are presented.

Acquired Immunodeficiency Syndrome↗
PubMed2006

Change in mobility activity in the second year after stroke in a rehabilitation population: who is at risk for decline?

OBJECTIVES: To investigate the development of mobility status during the second year after stroke in patients who had had inpatient rehabilitation, and to evaluate risk factors for mobility decline. DESIGN: Evaluation of change in Rivermead Mobility Index (RMI) score over the second year after stroke in an inception cohort of first-ever stroke patients eligible for inpatient rehabilitation. Logistic regression techniques were used to predict decline. Independent variables were measured with standardized instruments 1 year after stroke. SETTING: Home or institution, after discharge from rehabilitation center. PARTICIPANTS: Patients (N=148) with single first-ever stroke (supratentorial), age more than 18 years. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Decline of 2 or more points on the RMI and the percentages and odds ratios (ORs) for decline. RESULTS: The mean RMI score did not significantly change over time. Mobility declined in 12% of the patients. Mobility decline was found more often in patients with depression (25%) than without (7%), with right-sided weakness (17% vs 8%), with ischemic stroke (13% vs 8%), with aphasia (22% vs 11%), with cognitive dysfunction (17% vs 11%), with comorbidity interfering with locomotion (25% vs 12%), with poor social functioning (15% vs 10%), and with mobility disability (16% vs 8%). Statistical significance was found only for depression (OR=4.2; 95% confidence interval, 1.3-13.2). CONCLUSIONS: Most patients maintained the level of mobility they achieved during inpatient rehabilitation over the second year after stroke. Only 12% had a decline in mobility, and depression was the only statistically significant predictor for decline.

Activities of Daily Living↗
PubMed2005

Education modifies the effect of apolipoprotein epsilon 4 on cognitive decline.

OBJECTIVES: To assess the influence of education on the association between apolipoprotein E and cognitive change. DESIGN: Prospective cohort. PARTICIPANTS: HMO-based sample of 2168 non-demented community-dwelling elderly followed over 6 years. MEASUREMENTS: Generalized estimating equations were used with the difference between baseline and follow-up cognitive abilities screening instrument (CASI) as the outcome variable. RESULTS: At follow-up, 6% of the sample had a decline of 1.5 S.D. or greater on the CASI. Compared to individuals without an APOE4 allele, individuals with a single APOE4 allele did not have greater CASI decline. By contrast, individuals with two APOE4 alleles experienced greater decline in cognitive performance and the magnitude of that decline decreased as years of educational attainment increased. These relationships held after adjusting for age, gender, ethnicity, depression, diabetes, and history of vascular disease. CONCLUSION: Lower education was associated with steep 4-year cognitive decline for APOE4 homozygotes but not for APOE4 heterozygotes. Potentially modifiable host factors such as education could influence the association of high-risk genotypes and cognitive decline.

Age Factors↗
PubMed2004

Scanning laser polarimetry of the retinal nerve fiber layer in perimetrically unaffected eyes of glaucoma patients.

PURPOSE: To compare scanning laser polarimetry (SLP) measurements of retinal nerve fiber layer (RNFL) thickness in perimetrically unaffected eyes of glaucoma patients with those in their fellow eyes with field loss and eyes of healthy subjects. DESIGN: Observational case-control study. PARTICIPANTS AND CONTROLS: Twenty-three glaucoma patients with a reproducible visual field (VF) defect in one eye (mean mean deviation [MD], -5.71 decibels [dB]) and a normal VF in the other one (i.e., < or =1 VF test point below the 5% probability level [mean MD, -0.01 dB]) and 73 control eyes of as many age-matched healthy subjects (mean MD, 0.39 dB). The MDs and pattern standard deviations of the glaucoma patients' eyes with normal VFs and the control eyes did not statistically significantly differ (independent samples t test, P = 0.15 and P = 0.61, respectively). METHODS: All subjects were measured in both eyes with the GDxVCC, a commercially available instrument featuring SLP with automated variable corneal compensation. Standard automated perimetry was assessed by means of the Humphrey Field Analyzer (24-2 Full Threshold or Swedish interactive threshold algorithm Standard achromatic test program). MAIN OUTCOME MEASURES: The standard GDxVCC parameters TSNIT (temporal, superior, nasal, inferior, temporal) Average, Superior Average, Inferior Average, TSNIT Std. Dev., and Nerve Fiber Indicator (NFI) were determined. We also assessed the thickness values in 6 parapapillary sectors. In addition, we calculated the proportion of eyes per group with an NFI of > or =40. RESULTS: GDxVCC measurements showed more RNFL thinning in the perimetrically unaffected eyes of glaucoma patients than in the healthy control eyes. The RNFL in the perimetrically unaffected eyes of glaucoma patients was thicker than that in their fellow eyes with field loss. The NFI had a value of > or =40 in 11 of 23 (47.8%) perimetrically unaffected eyes of glaucoma patients, 19 of 23 (82.6%) eyes with VF loss of glaucoma patients, and 3 of 73 (4.1%) healthy control eyes. CONCLUSION: With the GDxVCC, thinning of the RNFL may be detected in perimetrically unaffected eyes of glaucoma patients with field loss in their fellow eyes.

Adult↗
PubMed2006

Predicting domain-specific insight of schizophrenia patients from symptomatology, multiple neurocognitive functions, and personality related traits.

This study examines the contribution of various neurocognitive functions, clinical characteristics, and personality traits to the prediction of three insight dimensions. Clinically stable schizophrenia patients (n=107) residing in the community were evaluated using the Positive and Negative Syndrome Scale, the Scale for the Assessment of Unawareness of Mental Disorder, and a comprehensive battery of instruments to measure personality related variables and neurocognitive functioning. Step-wise multivariate regression analysis indicates significant association of variability in insight dimensions with neurocognitive functioning (20-41%), personality related traits (8-18% temperament factors, 4-7% self-constructs, 10-14% coping styles), severity of symptoms (about 7%), illness duration (6%), and education (about 5%). Poor insight was attributed to impairment in visual and movement skills, sustained attention, executive functions, intensity of autistic preoccupations and positive symptoms, as well as increased novelty seeking behavior, task and emotion oriented coping styles, better self-esteem, self-efficacy, and higher education. Better awareness was related to better performance of neurocognitive tasks, reward dependence behavior, avoidant coping style, and longer illness duration. Aside from common indicators for the various insight dimensions, we defined specific indicators for each insight dimension. Thus, insight dimensions in schizophrenia patients residing in the community were attributed to neurocognitive and personality related factors rather than to psychopathological symptoms. The findings enable better understanding of the multifactorial nature of insight and highlight targets for more effective intervention and rehabilitation.

Adaptation, Psychological↗
PubMed2000

Self-perceived exertion level and objective evaluation of neuromuscular fatigue in a training session of orchestral violin players.

The aim of the study was to investigate the self-perceived exertion level and an objective measurement of muscle fatigue on violin players before and after a training session. Fourteen professional violin players volunteered in this study. Surveillance study was used to investigate the demographic characteristics, instrument playing background, playing habits variables and factors associated with playing-related musculoskeletal complaints (PRMCs). The subjective rating of the training-induced exertion was evaluated by the Borg scale ratings of perceived exertion (RPE). Surface electromyography (EMG) was used to record the fatigue level of the upper trapezius muscles before and after a training session. Medium frequency (MF) of the EMG signals was used to document the fatigue rate of this muscle. Descriptive statistics revealed a 79% prevalence rate of PRMCs with neck and shoulder region accounting for 57.1% of the areas reported. On the self-perceived exertion level associated with the training session, results indicated a significant increase in fatigue level (p = 0.003) after the training session. Regression analysis and paired samples t-tests revealed no significant difference in the slopes of MF on both sides of trapezius muscle, before and after the training sessions. The disparity in the subjective perception with the objective findings indicated that the violinists' self-perceived exertion arises from multiple sources. The high prevalence of PRMCs in this profession warrants further ergonomic investigation of possible work-related risk factors.

Adult↗
PubMed2002

Perceived safety climate, job demands, and coworker support among union and nonunion injured construction workers.

PROBLEM: This study evaluated injured construction workers' perceptions of workplace safety climate, psychological job demands, decision latitude, and coworker support, and the relationship of these variables to the injury severity sustained by the workers. METHODS: Injury severity was assessed using the Health Assessment Questionnaire (HAQ), which evaluates functional limitations. Worker perceptions of workplace variables were determined by two instruments: (a) the Safety Climate Measure for Construction Sites and (b) the Job Content Questionnaire (JCQ). RESULTS: The overall model explained 23% of the variance in injury severity, with unique contributions provided by union status, the Safety Climate Score, and Psychological Job Demands. A positive significant correlation was found between injury severity and the Safety Climate Scores (r = .183, P = .003), and between the Safety Climate Scores and union status (r = .225, P < .001). DISCUSSION: There were statistically significant differences between union and nonunion workers' responses regarding perceived safety climate on 5 of the 10 safety climate items. Union workers were more likely than nonunion workers to: (a) perceive their supervisors as caring about their safety; (b) be made aware of dangerous work practices; (c) have received safety instructions when hired; (d) have regular job safety meetings; and (e) perceive that taking risks was not a part of their job. However, with regard to the 49-item JCQ, which includes Coworker Support, the responses between union and nonunion workers were very similar, indicating an overall high degree of job satisfaction. However, workers who experienced their workplace as more safe also perceived the level of management (r = -.55, P < .001) and coworker (r = -.31, P < .001) support as being higher. IMPACT ON INDUSTRY: The findings of this study underscore the critical need for construction managers to alert workers to dangerous work practices and conditions more frequently, and express concern and praise workers for safe work in a manner that is culturally acceptable in this industry. Workplace interventions that decrease the incidence and severity of injuries, but that are flexible enough to meet a variety of potentially competing imperatives, such as production deadlines and client demands, need to be identified.

Accidental Falls↗