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PubMedDate not supplied

Peer rejection, social behavior, and psychological adjustment in children with juvenile rheumatic disease.

OBJECTIVE: To examine the associations among disease status, social competence, and depressive symptoms in children with juvenile rheumatic disease (JRD) and to test the hypothesis that individual differences in children's social competence account for a significant proportion of variance in depressive symptoms after controlling for disease status variables. METHOD: Thirty-six children with JRD completed standardized instruments to assess pain, health status, and depressive symptoms. The rheumatologist completed a disease severity measure, and teachers provided ratings of peer rejection and social behavior. RESULTS: Pain, peer rejection, and problematic social behavior were all positively associated with depressive symptoms. Social variables remained significantly associated with depressive symptoms after controlling for level of pain. In addition, peer rejection moderated the association between pain and depressive symptoms, such that children with high levels of pain and high levels of peer rejection reported the highest frequency of depressive symptoms. CONCLUSIONS: Health care providers should assess the social functioning of children with JRD in order to identify socially vulnerable children who may be at increased risk for internalizing problems.

Adaptation, Psychological↗

PubMed2001

[Motor behavior in depression: applications and limitations of actigraphic analyses].

OBJECTIVE: Alterations of motor behavior in depression play a key role in psychosocial activities and interpersonal communication and are relevant for differential diagnosis and treatment. Functions and application of actigraphy and empirical findings in depression will be summarised and discussed. METHODS: The current knowledge retrieved from information of manufacturers, Medline, PsycLIT, and PSYNDEX regarding features of actigraphic equipment and clinical aspects of gross motor analysis in depression was examined. RESULTS: Actigraphy is a practical method to monitor and quantify gross motor activity, but setting variables including sensitivity or epoch length vary among commercially available instruments. Measures of motor activity in depressed patients are used for diagnosis, evaluation of sleep, and prediction of treatment response. CONCLUSIONS: Measurements of motor behavior by actigraphy can be used in depression for diagnostic procedures and treatment evaluation. The role of actigraphic setting variables needs further clarification. Actigraphy may be used for behavioral analysis including individual regulation of motor activity as an objective parameter for evaluation of depression and other psychiatric disorders.

Activities of Daily Living↗

PubMed2001

[Heidelberg Centenarian Study: theoretical and methodological principles for social science research of the oldest old].

This paper addresses two important issues of oldest old research. First, we try to answer the question whether differences between extremely old persons are based on enduring aging processes of physical, social and psychological functions, or whether they are the result of selective survival weeding out the frail. Both trajectories predict low variability, but on different levels. Second, we investigate to which extent the variability of extremely old persons can be assessed by traditional psychosocial instruments. One hundred and fifty six centenarians were contacted, of whom 91 centenarians and 86 proxies participated in this study. The distribution of the cognitive status reveals a high amount of variability. In contrast, with respect to functional capacity 83% receive support from the German Statutory Insurance System for Long-Term Care. The higher variability in the psychological variable points to adaptive potential. We assume that in extreme old age various resources are used to maintain physical functioning above a critical threshold.

Activities of Daily Living↗

PubMed1993

Components of health: an analysis in rheumatoid arthritis using quality of life questionnaires and clinical and laboratory variables.

OBJECTIVE: To gain insight into the overlap between additional information supplied by recently developed health status instruments for rheumatoid arthritis (RA) and traditional clinical and laboratory tests. METHODS: A cross sectional study of 282 outpatients with RA was made. From each patient, variables of clinical and laboratory measurements were obtained and the modified health assessment questionnaire (MHAQ) and a Dutch quality of life questionnaire, the IRGL, were completed. These variables were analysed for their interrelationship. RESULTS: Clinical and laboratory variables correlated significantly with the scales of the physical dimension and the disease impact scale of the IRGL. Their significant correlations with the IRGL psychological scales were weak. There were no significant correlations between any of the traditional variables and the IRGL social scales. Factor analysis yielded five factors: functionality, pain, depressive mood, social support, and laboratory. The laboratory factor is a measure of the disease process. The other four factors provide a health model. CONCLUSION: The results suggest that the IRGL questionnaire that was studied covers a complete health model that incorporates aspects of health that are not measured by clinical and laboratory tests. A simple questionnaire for the psychological and social dimension of health status, however, would probably be more cost effective and easier to use in clinical practice.

Adult↗

PubMed2000

The statistical variability of blood alcohol concentration measurements in drink-driving cases.

Like many other places in the world, Hong Kong has drink-driving legislation which prohibits a driver from having in his blood alcohol exceeding a prescribed limit while in control of a motor vehicle. The accuracy of measuring this alcohol concentration is obviously of prime concern as an erroneous result can avert the administration of justice. The common practice is to deduct all errors from the measured value and compare the deducted value with the prescribed limit, so that the benefit of all errors of the measurement is given to the driver. It is therefore important for any laboratory responsible for measuring blood alcohol concentrations to identify and quantify all errors associated with the measurement. The present study examined 900 blood alcohol determinations carried out by the Hong Kong Government Laboratory (HKGL) on cases of suspected drink driving. The determinations were performed by 5 different analysts with two different sets of instruments during 1995-1997. Statistical analysis indicated that the instruments had no bearing on the random error or variability and that even though analyst was a significant factor on variability, the deviation from the mean so caused was only 0.3% and of no practical significance. When the systematic error introduced by the tolerance limits of the certified alcohol standards (purchased from the Laboratory of Government Chemists, UK) was taken into account, the total uncertainty (random plus systematic errors) of an alcohol determination at 99.5% confidence level was found to be 4%. It is recommended that laboratories engaged in blood alcohol determination should adopt similar statistical treatment of their analytical results to find out the error and to ensure that the results are independent of analyst and instrument used.

Automobile Driving↗

PubMed1999

Personality disorder traits: prevalence and effects on health status in primary care patients.

OBJECTIVE: Previous work in an academic setting has found that scoring in the higher ranges for selected personality disorders on an objective assessment tool was associated with increases in psychiatric co-morbidities, decreased satisfaction with health care, and diminished health related functional status. This study examines how often patients in primary care practices exhibit traits consistent with these selected disorders and what impact this has on their health related functional status and use of health care resources. METHODS: Thirteen family practices agreed to distribute questionnaires to 50 consecutive patients in the spring of 1997. Questionnaires contained instruments that assess risk for personality disorders, health related functional status, health resource use, demographics, and depression. The relationships between four specific personality disorders (borderline, dependent, schizoid and schizotypal) and other assessed variables were explored. RESULTS: Of the 250 patients returning completed survey instruments, 80 (32%) scored in the high range for traits consistent with one of the four target personality disorders. Patients in the high risk group also were noted to have more outpatient, emergency, and inpatient visits in the previous six months. Those in the high risk group also had significantly lower scores on seven of eight measures of health related functional status. CONCLUSIONS: Patients who have several traits for borderline, dependent, schizoid, and schizotypal personality disorders are common in primary care practices. These patients utilize services at higher rates than others and are more likely to screen in the positive range for depressive symptoms and have overall lower health related functional status.

Adolescent↗

PubMed1999

[Measure of parental behavior during children's ambulatory surgery].

A new instrument, l'Inventaire des conduites parentales, was validated by the main author during her doctoral studies. The purpose of her research was to measure the effect of an educational intervention on parent's behaviors. This instrument, based on an educational theoretical framework, was composed of 16 behaviors divided into 3 categories: verbal information, cognitive strategies and attitudes. The reliability of the initial version of the instrument was measured with a sample of 142 parents. The interrater agreement was of 94.3%. The factor analysis showed that 14 of the 16 items were closely related to 4 clusters of variables. Following the factor analysis results, and the utilization of this instrument by research assistants, it was revised and is now described in this article.

Adult↗

PubMed1987

Traditional approaches to functional assessment in arthritis.

Both clinical rheumatology and medical rehabilitation have traditional functional assessment approaches to patients with arthritis. Drawing from both, a suggested "universe of function" for rheumatic disease patients is presented. The variables included begin with components of the physical examination and continue to maneuvers performed by the patient, mobility, activities of daily living (ADL), upper extremity function, extended living functions, and global assessment instruments. The development of standardized methodologic techniques is greater for some variables, especially ADL. In all, there is a need for a consensus approach so that aggregate data generated in different studies and programs will be more comparable.

Arthritis, Rheumatoid↗

PubMed2004

Dimensions of oral health related quality of life measured by EQ-5D+ and OHIP-14.

BACKGROUND: The aims of the study were to compare the dimensions of oral-health-related quality-of-life measured by a generic health state measure, the EuroQol, and a specific oral health measure, the Oral Health Impact Profile. METHODS: Data were collected in 2001-02 from a random sample of South Australian dentists using mailed self-complete questionnaires. Dentists recorded the diagnosis of dental problems and provided patients with self-complete questionnaires to record the nature, severity and duration of symptoms using the EuroQol (EQ-5D+) and 14-item version of the Oral Health Impact Profile (OHIP-14) instruments. RESULTS: Data were available from 375 patients (response rate = 72%). The EuroQol items of mobility, self care and usual activities formed a separate cluster of variables, as did anxiety/depression and cognition, while pain clustered with items from the OHIP physical pain subscale. OHIP items tended to form clusters consistent with the subscales of social disability, physical disability, physical pain, functional limitation and psychological discomfort. The OHIP handicap items clustered between the OHIP social disability and physical disability subscales. The OHIP psychological disability items split between the social disability and psychological discomfort subscales. CONCLUSIONS: The observed clusters of variables empirically supported most of the conceptual dimensions of the OHIP. Both instruments covered symptom experience of pain indicating overlapping domains. However there was partial separation of the generic and specific items, EuroQol covered daily activities such as self-care and usual activities and OHIP covered oral health-specific aspects of functional limitation and physical disability as well as psychological and social aspects of disability and handicap.

Cost of Illness↗

PubMed2005

Development of a structural model explaining medication compliance of persons with schizophrenia.

The purpose of this study was to develop and test a structural model explaining medication compliance of schizophrenia. From a review of the literature, a hypothetical model was developed based on the conceptual framework of the Health Belief Model with medication knowledge, symptom severity and social support as the exogenous variables, and perceived benefits, perceived barriers, substance use and medication compliance as the endogenous variables. Data was collected at various mental health facilities, including psychiatric outpatient clinics of general hospitals and community mental health centers, between March and May, 2001. A structured questionnaire was used by one- on- one interviews to collect data on 208 schizophrenic patients. Well established measurement instruments, with confirmed reliability, were used to assess each method variable. As a result of covariance structural analysis, the hypothetical model was found not to fit the empirical data well, so a parsimonious model was adopted after modifying the model. The final model was able to explain the 33 % medication compliance. Medication knowledge, social support and perceived benefits had significant effects on medication compliance. The findings of this study address the importance of medication education and social support to promote medication compliance. It is also suggested that various education programs and support groups are needed to enhance medication compliance.

Adult↗

PubMed2002

Daily exercise reduces measures of heart rate and blood pressure variability in hypertensive rats.

This study was designed to test the hypothesis that daily spontaneous running (DSR) reduces measures of heart rate and blood pressure variability in spontaneously hypertensive rats (SHR). After 8 weeks of DSR or sedentary control, rats were chronically instrumented with arterial catheters. Daily exercise reduced most measures of heart rate (HR) and blood pressure variability. Specifically DSR decreased heart rate, Low Frequency Power (LF: 0.19-0.61 Hz), and Low Frequency/High Frequency (HF: 1.2-2.5 Hz) ratio of HR. Furthermore, Total Power (TP), LF power, and LF/HF ratio of systolic blood pressure were reduced by daily spontaneous running. Finally, TP, LF and HF powers and LF/HF ratios of diastolic blood pressure were reduced by daily spontaneous running. These data demonstrate that daily exercise reduces sympathetic activity and possibly increases cardiac reserve in hypertensive animals.

Animals↗

PubMed2001

Co-oximetry interference by hemoglobin-based blood substitutes.

UNLABELLED: The blood substitutes now being developed from molecularly modified hemoglobin interfere with a wide variety of clinical analyzers, but their effects on cooximeters are unknown. Therefore, we investigated the effects of five hemoglobin-based blood substitutes on the measurements of eight different oximeters and cooximeters: the AVL Omni 6, the AVOXimeters 1000 and 4000, the Ciba Corning (now Bayer) CC270 CO-Oximeter, the Instrumentation Laboratory Synthesis 35, the IL482 and IL682 CO-Oximeters, and the Radiometer OSM3 Hemoximeter. The five blood substitutes in this study were obtained from Apex Bioscience (Research Triangle Park, NC), Baxter Healthcare Corp. (Deerfield, IL), Biopure Corp. (Cambridge, MA), Hemoglobin Therapeutics, and Hemosol, Inc. (Etobicoke, Ontario, Canada). A cooximeter control was used to compare the eight different instruments' measurements on unaltered human hemoglobin. The instruments yielded measurements of total hemoglobin concentration in undiluted blood substitutes that were generally not more variable than those on the control material. By contrast, when compared with readings on controls, the test instruments yielded measurements of the fractional concentrations of oxy-, deoxy-, carboxy-, and methemoglobin that showed greater instrument-to-instrument disparities and larger standard deviations about the all-instrument means. In some cases, the interference was even more obvious: five of six cooximeters gave negative carboxyhemoglobin readings on one particular product. Our findings indicate that the instruments will give less accurate but clinically useful measurements in the presence of these hemoglobin-based blood substitutes. IMPLICATIONS: We investigated the effects of five hemoglobin-based blood substitutes on the measurements of eight different cooximeters. Some blood substitutes caused obvious interference, such as negative carboxyhemoglobin readings; however, the findings indicate that cooximeters will generally give less accurate but clinically useful measurements in the presence of the hemoglobin-based blood substitutes that were tested.

Algorithms↗

PubMed1996

Direct and indirect effects of demographic, medical, and psychological variables on neuropsychological performance in normal geriatric persons: a structural equation model.

The direct and indirect effects of demographic, medical, and psychological variables on neuropsychological performance in elderly individuals were examined using a LISREL structural equation model. One-hundred fifty-six geriatric subjects were individually administered a comprehensive neuropsychological battery, an extensive medical history and demographics questionnaire, and the Neuropsychology Behavior and Affect Profile (a psychological assessment instrument). The model assessed the effects of five independent latent variables (medical history, psychological functioning, global mental status, education, and gender-related functioning) on two dependent latent variables (nonverbal and verbal neuropsychological functioning). The best fitting model revealed that three latent variables (medical history, global mental status, and gender-related functioning) had direct effects on neuropsychological functioning and that all five independent variables exhibited indirect effects. These findings suggest that the influence of demographic variables on neuropsychological functioning for geriatric persons is complex and that certain variables should not be interpreted independently of each other due to their significant moderating influences.

Aged↗

PubMed2004

Image-based computer-assisted total knee arthroplasty leads to lower variability in coronal alignment.

In a prospective randomized controlled trial, one group of 50 patients had total knee arthroplasty using conventional instruments; another group of 50 patients had total knee arthroplasty using a fluoroscopy-based computer navigation system. The variability of postoperative alignment of the lower limb in the coronal and saggital plane, early clinical outcome scores, and morbidity of the procedure were compared. In addition, the image-based computer navigation system was used to assess the following presumptions: the accuracy of the calculation of the kinematic center of rotation of the hip and the reliability of full-leg standing xrays in determining overall coronal alignment of the lower limb. Variability in the coronal plane was significantly reduced in the computer-assisted surgery group compared with the conventional group (p < 0.0001). Early clinical outcome and complication rates were similar for both groups. The correlation between full-leg standing xrays and the computer navigation system for determining the mechanical alignment of the lower limb in the coronal plane was high (r = 0.987). The maximum deviation between the calculated kinematic center of rotation of the hip and the fluoroscopically determined anatomic center of the hip was 5 mm (mean, 1.6 mm). An image based computer-assisted system can be safely used and leads to a consistent and perfect postoperative alignment in the coronal plane.

Adult↗

PubMed1999

Impact of bone mineral estimates on percent fat estimates from a four-component model.

PURPOSE: The primary purpose of this study was to determine the impact of bone mineral content (BMC) from QDR 1000/W and DPX-L dual-energy x-ray absorptiometers (DXA(QDR) and DXA(DPX-L) on percent fat (%fat) estimates from a four-component model. A secondary purpose was to test the accuracy of %fat estimates from DXA(QDR) and DXA(DPX-L) using %fat estimates from a four-component model as the criterion. METHODS: Percent fat, fat mass, and fat-free mass (FFM) were determined from DXA(QDR) and DXA(DPX-L) and from a four-component model based on measures of body density from underwater weighing, body water from deuterium dilution, and BMC from DXA(QDR) (4C(QDR)) or DXA(DPX-L) (4C(DPX-L)) in young men (N = 14) and women (N = 10). RESULTS: BMC was significantly lower using DXA(QDR) compared with DXA(DPX-L) (approximately 11%), resulting in slightly lower estimates of %fat and fat mass and slightly higher estimates of FFM from 4C(QDR) than 4C(DPX-L). Although estimates of %fat, fat mass, and FFM from DXA(QDR) and DXA(DPX-L) were not different than those from a four-component model, there was considerable individual variability between methods. Furthermore, %fat from DXA(QDR) was lower than %fat from 4C(DPX-L). CONCLUSIONS: We conclude that using BMC from different DXA instruments has a minimal impact on %fat, fat mass, and FFM estimates from a four-component model. The large variability in %fat estimates between the two DXA instruments and those from a four-component model does not support DXA as a criterion method of body composition. Further studies involving larger sample sizes and specific population groups are needed to assess the validity of body composition measurements from DXA.

Absorptiometry, Photon↗

PubMed1993

Nutritional risk and survival in elderly veterans: a five-year follow-up.

The purpose of this study was to identify predictors of survival over five years in a sample of 377 elderly (age 55+) chronically ill men. Subjects were selected at baseline from consecutive appointments at a geriatric clinic and given extensive medical and psychosocial assessment. Five years later, subjects who could be located were interviewed by telephone. Interviews were completed with 194 (51.4%) subjects, 90 others were confirmed as deceased, 29 subjects could not be interviewed, and 64 more were not located although VA records did not show that any were deceased. The predictor variable of interest was the Nutritional Risk Index (NRI), a 16 item index which measures nutritional dimensions of health status. Other variables included functional health status [Activities of Daily Living (ADL), Instrumental Activities of Daily Living (IADL)], mental health status [Mini-Mental Status Exam (MMSE), morale], health habits (smoking, alcohol use and exercise), use of health services (physician visits, emergency room (ER) visits, hospital stays), and demographic factors (age, income, marital status and living arrangements). Proportional hazard models showed that the variables with statistically significant direct effects on survival time were younger age, higher functional health status on IADL, non-smoking, moderate alcohol use, and perception of adequate income. Nutritional status was indirectly associated with survival.

Activities of Daily Living↗

PubMed1996

Thoracic volume changes in scoliosis surgery.

STUDY DESIGN: Eighteen patients with adolescent idiopathic scoliosis treated with ISOLA instrumentation and 13 treated with Cotrel-Dubousset instrumentation were studied before and after surgery with computed tomography scans. OBJECTIVES: To analyze and compare the immediate change in chest volume of patients treated with the derotation method of Cotrel-Dubousset versus the sublaminar wire translational technique of ISOLA. SUMMARY OF BACKGROUND DATA: Previous literature suggests a small but variable improvement in pulmonary function with the use of Harrington instrumentation when treating adolescent idiopathic scoliosis. The effect of modern instrumentation techniques on chest volume and ultimately pulmonary function has not been determined. METHODS: An axial computed tomography slice was made through each vertebral body from T3 to T10. Using a technique of spine curve measurements, the cross-sectional area at each level was computed, and from the height measured, the volume of the thoracic cage was computed. RESULTS: Single thoracic curves (King-Moe Type III) managed with ISOLA sublaminar instrumentation showed a statistically significant increase in chest volume when compared with other curve types and when compared with all curves managed with Cotrel-Dubousset. Seventeen of 18 patients treated with ISOLA instrumentation gained chest volume, whereas half of those treated with Cotrel-Dubousset actually lost volume. CONCLUSIONS: ISOLA instrumentation and sublaminar wiring appears to increase the chest volume in patients with adolescent idiopathic scoliosis. Its clinical significance remains to be determined.

Adolescent↗

PubMed2002

Methodology of three-dimensional determination of root surface roughness.

In comparing and evaluating the instruments that are used in root debridement, roughness constitutes a standard variable that is assessed. The purpose of this study was to describe the conditions and requirements for the three-dimensional roughness measurements of tooth roots using a laser profilometer. Impressions were made of 60 instrumented and 12 untreated root surfaces, which were then measured using a dynamically focussing optical profilometer (Mikrofocus, UBM, Karlsruhe, Germany). To separate roughness from the form of the tooth, a low pass filter was applied. This meant that the longer wavelengths - which roughly approximated the root forms - were subtracted from the measured profile. We then used an individualized Fourier transformation to define the threshold at which roughness becomes waviness. Roughness parameters were Ra (average roughness) and Rz (average roughness in the z dimension) for two- and three-dimensional measurements. To describe the requirements for the measurement, we studied the effect of pixel density and the field size on the average roughness value, Ra. We found that Ra increases with pixel density until 400 per mm is reached, after which it does not change meaningfully. Furthermore, Ra is highly dependent upon the area of the field to be scanned, increasing in line with the area, and does not approach one value within the surface available on one tooth. The correlation coefficients between the two-dimensional and three-dimensional Ra and Rz values ranged from 0.7 to 0.8. We conclude that roughness values are strongly dependent on the measurement conditions and the results of one study cannot be directly compared to another. In addition, it was found that two-dimensional measurements are sufficient for characterizing root surfaces.

Dental Scaling↗