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Results for “instrumental variable”

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PubMedDate not supplied

Pain-related distress and interference with daily life of ambulatory patients with cancer with pain.

PURPOSE/OBJECTIVES: To examine the unique and combined effects of pain intensity, pain-related distress, analgesic prescription, and negative mood on interference with daily life because of pain. DESIGN: Descriptive, cross-sectional. SETTING: Two cancer clinics in academic medical centers in the southeastern United States. SAMPLE: 64 ambulatory patients with cancer who had pain that required analgesics. METHOD: Participants completed a number of self-report instruments during a regularly scheduled clinic visit. Standard instruments were selected to measure the main research variables. MAIN RESEARCH VARIABLES: Worst pain intensity, pain-related distress, analgesic adequacy, negative mood, and interference with daily life. FINDINGS: Patients with higher levels of worst pain, pain-related distress, and negative mood and inadequately prescribed analgesics reported greater interference with daily life because of pain. Multiple regression analysis indicated that interference with daily life was explained by the combination of these four predictors. All variables except negative mood were significant predictors of interference. The unique variance explained by pain-related distress exceeded that explained by worst pain intensity or inadequately prescribed analgesics. CONCLUSIONS: Data suggest that pain-related distress may be an important factor when investigating interference with daily life caused by pain. In addition, pain-related distress may provide a target for future intervention studies aimed at improving the impact of cancer-related pain on daily life. IMPLICATIONS FOR NURSING: Assessment of pain-related distress may be important in planning interventions. Common nursing interventions may be employed to reduce pain intensity and pain-related distress, which may result in enhanced physical and emotional well-being.

Activities of Daily Living↗
PubMed2004

Sleep-wake disturbances in people with cancer part II: evaluating the evidence for clinical decision making.

PURPOSE/OBJECTIVES: To evaluate the quality of evidence on sleep-wake disturbances in people with cancer as a basis for clinical decision making and to discuss implications of the evidence for oncology clinicians, educators, and researchers. DATA SOURCES: Published, peer-reviewed articles. DATA SYNTHESIS: Members of the 2001 Oncology Nursing Society (ONS) Advanced Practice Nurse Retreat Evidence-Based Practice Sleep Working Group selected and evaluated data sources using criteria and processes outlined by ONS. CONCLUSIONS: The development of nursing science related to sleep-wake disturbances among people with cancer and the application of research findings to clinical decision making are limited by the quantity and quality of published evidence. IMPLICATIONS FOR NURSING: Clinicians are challenged to develop a plan of care that includes the assessment of sleep-wake disturbances and interventions to address them. Nurse educators are challenged to include sleep-wake content and skills to evaluate empirical data and interventions for sleep-wake disturbances in degree and continuing education curricula. Nurse researchers are challenged to specify consistent conceptual and operational definitions of key variables in sleep-wake models, use measurement instruments with evidence of reliability and validity, and design clinical trials to test interventions for sleep-wake disturbances among people with cancer.

Adult↗
PubMed1995

Use of the Wechsler Memory Scale-Revised in traumatic brain injury.

The Wechsler Memory Scale-Revised (WMS-R) is a frequently used memory measure that has endured numerous criticisms, particularly related to the variability of results of factor analytic studies. The instrument relies on conglomerate Index scores to represent performance, in spite of tenuous empirical support. This study provides evidence that valuable information about memory abilities for individuals sustaining traumatic brain injury can be gained by investigating individual WMS-R subtest performance. The WMS-R was administered to a total of 54 subjects 36 individuals with moderate to severe TBI, and 18 normal controls. Results suggested that Index scores do not necessarily accurately represent performance on each of the individual Index subtests. Development of percentile scores for all subtests is strongly recommended, and implications for rehabilitation planning are discussed.

Journal Article↗
PubMed2006

[Protection factors against alcohol consumption promoted by pre-school teachers].

This study aimed to describe what protection factors against alcohol consumption are promoted by pre-school teachers at the department of San Alberto, Córdoba, Argentina. This is a quantitative and descriptive study. An auto-administrated instrumented was applied to 43 teachers. The study variables were submitted to descriptive statistical analysis. It was observed that, in a general and indirect way, the teachers' actions focused on the institutional and sociocultural protection factors, since a large part of the developed activities mainly refer to: Stimulating healthy habits, school climate, recreation, group strengthening and integration, interaction and participation in institutions and society. There is a need for the teachers to implement reformulated direct and concrete actions to solve the alcohol problem among pre-school students, with a view to a greater social impact.

Alcohol Drinking↗
PubMed1992

Longitudinal reliability of the Life Satisfaction Index (Short Form) with nursing home residents: a cautionary note.

We administered the Life Satisfaction Index (Short Form) 18 times over a 39-wk. period to an initial sample of 76 old, frail, multiply impaired, and depressed nursing home residents participating in a longitudinal quasi-experimental study of the effects of cognitive group interventions on cognition and depression. As no changes over time were observed on the outcome variable of life satisfaction, the stability of the instrument's internal consistency could be examined. Kuder-Richardson KR-20 coefficients ranged from .11 to .60, with a mean of .42 (SD = .11). We conclude that caution should be used when applying this instrument to measure life satisfaction in frail nursing home residents.

Aged↗
PubMed2002

The physical education climate assessment instrument.

This paper describes the Physical Education Climate Assessment Instrument designed for systematic observation and to quantify variables associated with different types of objective motivational climates created by teachers and coaches in physical education and sports practices. The theoretical framework which guided the development is outlined with recording procedures and methods by which data can be summarized. In addition, estimates of validity, reliability, and feasibility are reported.

Child↗
PubMed1993

Quality of Life--rationale and methods for developing a disease-specific instrument for inflammatory bowel disease.

Quality of Life (QOL) is a composite descriptor applied to an unlimited spectrum of tangible and intangible parameters of life satisfaction and capacity. Because of the breadth of determinants of QOL, most researchers prefer to focus on a specific segment of it, such as health-related quality of life (HRQOL). Generally, HRQOL indices incorporate physical, emotional and social aspects of both health perception and function. Most instruments are also subjective and quantitative. As in clinical trials, several elements are critical to the development of a HRQOL measure. Most importantly, the putative application of the instrument should be determined beforehand. The clinical setting and disease-specific population of interest must be identified. The questionnaire must be as simple as possible and easy to administer. The final instrument must be shown to be a valid measure of HRQOL, which is reproducible, with limited variability and observer bias on repeated administrations, when no clinical change has occurred. If applicable, the instrument should demonstrate responsiveness to important changes in clinical status. Finally, the value of the instrument in relevant clinical studies should be demonstrated. The critical phases of development of the McMaster IBDQ are outlined. The IBDQ is a quantitative index of HRQOL intended as a measure of therapeutic outcome for clinical trials in patients with inflammatory bowel disease.

Attitude to Health↗
PubMedDate not supplied

Degree of cognitive distortions and level of depression in bulimic patients.

A descriptive correlation design was used to study the relationship between the degree of cognitive distortions and the level of depression in bulimic patients. The theoretical framework was based on Beck's (1976) cognitive theory of depression. Beck viewed symptoms of depression as consequences of distorted thought processes. The instruments that were used to measure the study variables were the General Cognitive Error Questionnaire (Lefebvre, 1981) and the Beck Depression Inventory (Beck, Rush, Shaw, & Emery, 1979). The hypotheses for the study predicted that there would be a positive relationship between the degree of cognitive distortions and the level of depression in bulimic patients. The Pearson r was used to determine if a statistically significant relationship existed between degree of cognitive distortions and level of depression. Data analysis revealed that there was a significant relationship, r(28) = .586, r2 = .343, p less than .001, between the degree of cognitive distortions and level of depression in this study of 30 bulimic patients.

Adolescent↗
PubMed2006

Using and understanding factor analysis: the Brief Pain inventory.

Factor analysis is useful for examining relationships among large numbers of variables and understanding the conceptual structure of an instrument The Brief Pain Inventory (BPI), which measures pain in terms of its severity and interference with function, has been widely used with cancer patients. A secondary analysis of BPI data in a sample of postoperative patients is used to illustrate the factor analytic method. The resulting two-factor solution of pain's interference with function and pain severity are discussed by Margarete Lieb Zalon in relation to the validity of the BPI along with considerations in using the instrument with surgical patients.

Activities of Daily Living↗
PubMed1993

Haemodynamic changes associated with thermodilution cardiac output determination during metabolic acidosis or hypoxic hypoxia in dogs.

Haemodynamic alterations elicited by iced injectate during thermodilution cardiac output measurements were evaluated in the presence of metabolic acidosis or hypoxic hypoxia in 14 instrumented anaesthetized dogs. The alterations in some haemodynamic variables during slowing of the heart rate following injection of 3 ml iced injectate were slightly greater in metabolic acidosis and hypoxic hypoxia as compared to animals without metabolic acidosis or hypoxic hypoxia (P < 0.05), but the changes were clinically insignificant. No serious haemodynamic changes were found during any cardiac output measurement by thermodilution in the presence of metabolic acidosis or hypoxic hypoxia. The values of cardiac output measured by thermodilution correlated closely with those of pulmonary blood flow measured by an electromagnetic flowmeter in the metabolic acidosis and hypoxic hypoxia groups (r > 0.9). It is concluded that thermodilution using iced injectate will estimate right ventricular output accurately in conditions of metabolic acidosis and hypoxic hypoxia.

Acidosis↗
PubMed2002

A model to control intermittent aeration phases.

Dealing with intermittent aeration as a useful practice to improve nitrogen removal efficiency of activated sludge plants, the possibility to plan optimal temporisation during daytime was investigated. A mathematical model (NIDEN) that allows us to manage different situations, with respect to influent load, environmental conditions and operating strategy, was then developed. The model represents a useful tool especially to plan the aeration cycles in small and medium sized plants, where high costs of automatic control through on-line instrumentation might not be justified. Once the input variables have been defined and the set-point values for tank nutrient concentration have been fixed, NIDEN gives an optimal phase temporisation, to obtain either the maximum energy saving or the best total nitrogen removal.

Automation↗
PubMed2002

[Research of image spectrometer using linear variable interference filter].

In the present work we have designed a small-size portable imaging spectrometer using linear variable interference filter, with CCD camera as picture sensor, and micromotion stage to bring along interference filter which scan across every pixel of CCD array. The difference column pixel in the picture which we get at every step is monocolour partial image under different wavelength, with the step by step, these column monocolour pixels change the wavelength. And finally we reassembled these images and get the whole monocolour image with different wavelength. The interval of sweep step length decided by the required spectrum resolution and the required wavelength interval of different pictures. The experiment demonstrated the resolution of this spectrometer is about 16 nm, but that major reason of the limiting resolution is the band width of the linear variable interference filter. The spatial resolution of the instrument ultimately decided by CCD, filter and imaging lens. This spectrometer has some characters such as compact structure, higher spatial resolution, higher spectrum resolution, higher scan rate and so on. Furthermore, an application of this instrument in distinguishing from camouflage have been showed.

Analog-Digital Conversion↗
PubMed1992

Comparative study of the knowledge, attitudes, and behaviors of large animal veterinarians, dairy farmers, and dairy processors in Michigan on bovine somatotropin.

A cross-sectional epidemiologic study was conducted to evaluate two objectives. The first was to determine the knowledge, attitudes, and behaviors of large animal (dairy) veterinarians, dairy farmers, and dairy processors in Michigan toward the use of bovine somatotropin (BST). The second was to compare and contrast the data from the large animal veterinarians, dairy farmers, and dairy processors according to the knowledge, attitude, and behavior variables. A written questionnaire was used as an instrument to collect data relating to the objectives. Three basic types of questions were asked of each group: (1) how much do you know about BST? (knowledge-based question), (2) how do you feel about BST? (attitude-based question), and (3) how would you use BST or use dairy products produced through BST biotechnology (behavior-based question)?

Animals↗
PubMed1991

Karolinska Psychodynamic Profile. KAPP.

The Karolinska Psychodynamic Profile, KAPP, is a rating instrument founded upon psychoanalytic theory. Its validity is satisfactory, and high interrater reliability can be attained with modest training of the raters in using the instrument. It enables relatively stable and only slowly variable modes of mental functioning and character traits to be assessed psychodynamically. The profile is based upon eighteen subscales, by means of which these modes of mental functioning and character traits can be represented. The subscales have been chosen with a view to obtaining a comprehensive assessment of modes of mental functioning and character traits, as reflected in the patient's self-image and relationships with others. The subscales and their scale steps have been provided with relatively detailed descriptions which are kept close to clinically observable phenomena. The information needed for making the assessments is obtained through a structural interview procedure. The manual, the subscales and their scale steps, and the assessment procedure is presented.

Affective Symptoms↗
PubMed1982

Measuring hemoglobin in plasma by reaction with tetramethylbenzidine.

The reaction of hemoglobin with tetramethylbenzidine was studied with a centrifugal analyzer. We found that the hemochromogen reaction was significantly influenced by albumin. Increasing amounts of albumin apparently stimulate the hemochromogen reaction during the earlier part of an incubation and inhibit it later in the incubation. However, during an intermediate period, when the crossover from stimulation to inhibition occurs, the assay is independent of albumin and bilirubin concentrations. Increasing the temperature of incubation or the hydrogen peroxide concentration, or decreasing the tetramethylbenzidine concentration, shortens the crossover time. By adjusting these variables the method can be used with most instrumentation. We developed procedures for use on a centrifugal analyzer or for manual assay (reaction times, 4 and 20 min, respectively). Accuracy, as indicated by a comparison with a direct hemoglobin method (r = 0.990) and by recovery experiments, was excellent. The CV for the automated assay was less than 3%. Plasma collected in citrate and heparin showed good recovery of hemoglobin; recovery in EDTA was poorer.

Benzidines↗
PubMed1998

The relationship of family structure to adolescent drug use, peer affiliation, and perception of peer acceptance of drug use.

This study examined the relationship of family structure to adolescent gateway drug use and peer-related factors. The sample consisted of 2,121 randomly selected students in grades 8, 10, and 12 from seventeen school districts in northeastern Ohio. Students were administered a self-report instrument containing items measuring drug use and psychosocial variables. For purposes of analysis, the dependent variables included frequency of use of five gateway drugs, degree of affiliation with drug-using peers, and perceptions of peer acceptance of drug use. Comparison groups included single-parent (both mother- and father-headed), stepparent, and intact families. Analyses were conducted separately by grade level. Significant differences were found between groups on the drug-use variables at grades 8 and 10, with adolescents from intact families reporting less frequent drug use, fewer drug-using friends, and perceptions of more peer disapproval of drug use. Interestingly, there were several statistically significant group differences on perceptions of peer acceptance of drug use and the number of drug-using friends at the 8th-grade level. The largest differences were found between the single-parent (father-headed) and intact groups, with adolescents from father-headed families showing more frequent beer and liquor consumption at the 10th-grade level.

Adolescent↗
PubMed2001

Instrumentation in antimicrobial susceptibility testing.

Studies in the 1960s demonstrated the problems of variability in susceptibility testing methods, especially those affecting the performance of disc diffusion procedures. These studies made apparent the need for standardization and resulted in more clearly defined performance limits for growth medium, incubation conditions, inoculum concentration, disc content for diffusion methods, the setting of interpretative MIC breakpoints and the establishment of quality control parameters. More recently, there has been a growing interest in the use of instrumentation for reading disc diffusion tests and the endpoints of agar or broth dilution MIC determinations. Instrumentation ranges in complexity from the simple optical reading of zones of inhibition or growth endpoints, requiring operator interpretation, to more sophisticated devices for reading, recording and 'expert system' analysis of results with interfacing of instruments to laboratory information management systems. Some of the more developed systems are fully automated and can also identify the organisms tested. The pressure to reduce labour costs and provide results earlier favours the use of more automated systems whilst the requirement for resistance surveillance provides impetus for the use of systems that provide quantitative results and electronic data handling.

Bacteria↗
PubMed1980

Mechanisms of beat-to-beat variability in the heart rate of the neonatal lamb. I. Influence of the autonomic nervous system.

The contributions of the intrinsic, beta-adrenergic, and cholinergic systems to the mechanisms of beat-to-beat variability of the heart rate were investigated in chronically instrumented, unanesthetized newborn lambs from the first week to the eighth week of neonatal life. During this period of neonatal growth, the resting heart rate decreased spontaneously every week; the decrease was not related to alterations in the sympathetic and parasympathetic tones but rather to changes in the intrinsic mechanisms of heart rate control. Despite the weekly decrease in the resting heart rate of the neonatal lamb, the long and short-term beat-to-beat variabilities did not change significantly. This finding suggests an absence of a significant influence of the intrinsic mechanisms of heart rate control on the genesis of beat-to-beat variability. The results obtained with the various modes of adrenergic and cholinergic blockades and stimulation seem to indicate that the autonomic nervous system contributes significantly to the appearance of beat-to-beat variability. However, the influences of the adrenergic and cholinergic systems differ from week to week of neonatal growth and the patterns of changes are not the same for the long-term and short-term variabilities. The implication of these studies in terms of physiologic and hemodynamic significance of beat-to-beat variability in heart rate is discussed.

Aging↗