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PubMed1991

[The rating box--a new instrument for ambulatory detection of subjective variables].

For the acquisition of subjective variables in outpatients and inpatients, a new device--the Rating Box--has been designed. The Rating Box provides a standardized, date- and time-logged documentation of symptoms by the patient and rapid transfer of data to a personal computer. The simultaneous acquisition of several symptoms using different types of scales is possible. The acoustic alarm of the Rating Box reminds the patient to enter data at preselected times. The device is easy to handle, even by older patients, and has been successfully tested in the acquisition of pain variables in patients with a variety of painful conditions.

Data Collection↗
PubMed1997

Laboratory and clinical evaluation of a portable computerized peak flow meter.

A mini-Wright based peak flow meter (VMX Mini-Log), which stores the readings together with the time and date of each measurement, has recently been marketed but has not yet been evaluated. The accuracy, reproducibility, and interdevice variability of this instrument were investigated using a pneumotachograph connected in series as a standard. Flows from 100 to 700 L/min were generated by an explosive decompression chamber. The performance of this instrument was also tested in 20 normal subjects and in 20 patients with airflow obstruction. The accuracy of the instrument was expressed as the percentage of error, and reproducibility and interdevice variability were assessed using the coefficient of variation. In the laboratory evaluation, all devices recorded flow rates that were within +/-10% of the pneumotachograph readings at flows between 200 and 600 L/min. At the extreme flow rates of 100 and 700 L/min, the mean error was higher than 10%. The reproducibility of the VMX was within +/-5% at all the flows tested. The interdevice variability was less than 5% at flow rates between 200 and 700 L/min. When tested on normal subjects with PEF between 400 and 700 L/min, the VMX performed well. In patients with airflow obstruction, four devices had greater than 10% error. The largest error was observed in those patients with PEF below 200 L/min. The VMX Mini-Log peak flow meter is accurate and precise in the flow range between 200 and 600 L/min. Its performance, however, may be affected in subjects with airflow obstruction and PEF below 200 L/min.

Adolescent↗
PubMed1975

Some effects of anxiety and cognitive style upon pursuit rotor learning.

The present study sought to investigate the interrelationships between anxiety level and cognitive style upon pursuit rotor learning under conditions of relatively massed practice. The empirical specifications of anxiety were chosen so as to render the study comparable to previous investigations executed within the general framework of Spence's (1956, 1958) developments of Hull's (1943) notions concerning the relationship to drive level and learning task performance. The results were also related to Eysenck's (1956, 1964, 1965) elaborations of Hullian theory as related to motor learning phenomena. The cognitive style variable was assessed by a single measuring instrument, the Stroop Test. The variables tapped by this instrument were expressed within the framework of neo-Hullian theory, and predictions made from an expanded version of the theory. Subjects were constituted into four groups: Cognitive High-anxiety, Cognitive Low-anxiety, Perceptual-motor High-anxiety, and Perceptual-motor Low-anxiety. When the pursuit rotor task was administered, Perceptual-motor subjects excelled, as expected, as compared to Cognitive subjects. High-anxious Perceptual-motor subjects exhibited greater amounts of reminiscence than did Low-anxious Perceptual-motor subjects; unexpectedly, the reverse effect obtained within the Cognitive group, with the Low-anxious subjects showing more reminiscence. It is suggested that conditioned inhibitory effects might have appeared differentially within the groups.

Adolescent↗
PubMed2001

NMR of biofluids and pattern recognition: assessing the impact of NMR parameters on the principal component analysis of urine from rat and mouse.

The ability to interpret metabolic responses to toxic insult as expressed in altered urine composition and measured by NMR spectroscopy is dependent upon a database of proton NMR spectra of urine collected from both control and treated animals. Pattern recognition techniques, such as principal component analysis (PCA), can be used to establish whether the spectral data cluster according to a dose response. However, PCA will be sensitive to other variables that might exist in the data, such as those arising from the NMR instrument itself. Thus, studies were conducted to determine the impact that NMR-related variables might impart on the data, with a view towards understanding and minimizing variables that could interfere with the interpretation of a biological effect. This study has focused on solvent suppression methods, as well as instrument-to-instrument variability, including field strength. The magnitude of the NMR-induced variability was assessed in the presence of an established response to the nephrotoxin bromoethanamine. Changes caused by the model toxin were larger and easily distinguished from those caused by using different solvent suppression methods and field strengths.

Animals↗
PubMed1989

Black and Latina womens' AIDS related knowledge, attitudes, and practices.

As part of a larger study designed to provide an AIDS education and prevention program for low-income black and Latina women in Los Angeles County, a pilot study of black (n = 51) and Latina (n = 56) womens' AIDS related knowledge, attitudes and practices was conducted to gather baseline data and to test an instrument that would measure these variables. The factors underlying the instrument were identified and reliability coefficients were determined. The need for changes in the format and administration of the instrument was identified due to nonresponse to some items. There were sociodemographic differences between the two groups of women as well as differences in knowledge and attitudes. In general, black women had more knowledge of AIDS than Latina women and more positive attitudes. Practices did not differ. Both groups denied drug use and multiple sexual partners.

Acquired Immunodeficiency Syndrome↗
PubMed1982

Quantitative measurement of activity in small sources containing medium energy radionuclide: comparison of the gamma camera and the rectilinear scanner.

The response of a gamma camera and a rectilinear scanner to small sources containing 131I was assessed from the point of view of thier suitability for measuring the activity of a source, as opposed to their capacity to produce well-resolved images. The influence of the size of the area over which counts were integrated, and of the size and depth of hte source, were investigated for both instruments. The results indicate that both instruments are dependent on these variables, though with the particular instruments investigated the dependence of the gamma camera is much more complex and difficult to define. The conclusions indicate that with these systems quantitative activity measurements are more readily achievable with the scanner than with the camera.

Iodine Radioisotopes↗
PubMedDate not supplied

Development and psychometric testing of the Bakas Caregiving Outcomes Scale.

BACKGROUND: Family caregivers of stroke survivors experience more depression, emotional problems, social inactivity, and general ill-health than noncaregiving individuals. While a number of instruments measure these variables in family caregivers, they are often too global, indicating the need for a situation-specific instrument measuring life changes resulting from providing care. OBJECTIVES: To develop and psychometrically test the Bakas Caregiving Outcomes Scale (BCOS) measuring changes in family caregiving outcomes in the stroke population. METHOD: 48 items were developed, with 27 being judged as content valid by a panel of five experts. Psychometric testing with two convenience samples of family caregivers of stroke survivors (ns = 92, 104) was conducted using item analysis, Cronbach's alpha, factor analysis, and hierarchical multiple regression. RESULTS: Item analysis in sample no. 1 resulted in a 12-item scale with alpha = .90. The scale was further shortened to a 10-item scale in sample no. 2 with alpha = .77. Unidimensionality was supported by factor analysis in both samples. Using hierarchical multiple regression, 63% of the variance of the 12-item BCOS in sample no. 1, and 45% of the variance of the 10-item BCOS in sample no. 2 was accounted for by the constructs in the conceptual model. Criterion-related validity was supported in both samples by significant correlations with the LIFE-3 and a criterion variable with the same response format as the BCOS. Significant BCOS correlations with the SF-36 Health Survey subscales in sample no. 2 provided further evidence of criterion-related validity. CONCLUSION: The 10-item BCOS is a brief, easy to administer instrument that has evidence of reliability and validity in family caregivers of stroke survivors. The 10-item BCOS could serve as a valuable measure in research, as well as an assessment tool to identify family caregivers in need of intervention.

Caregivers↗
PubMed1996

Instrumentation for assessment of tremor, skin vibrations, and cardiovascular variables in MIR space missions.

A versatile and simple to use biomedical instrumentation for noninvasive examinations of cosmonauts at the Russian MIR space station was developed. It consists of a comfortable sensor jacket to assess signals from the body surface, a precision hand dynamometer to produce muscular and cardiovascular loads, and a small interactive microprocessor unit that controls the examination and stores measurement data. The sensor jacket includes highly sensitive piezo-resistive accelerometers, pulse sensors, an ECG system, and a skin-mountable mechanical vibrator. The functionality of this instrumentation was evaluated during long-term space flights and also proved very useful in laboratory and clinical studies.

Cardiovascular Physiological Phenomena↗
PubMed2000

A new bilateral closed chain assessment technique: methods and error analysis.

PURPOSE: The purpose of this paper is to present the Omnikinetic methodology for clinical evaluation of lower extremity function, to characterize its sensitivity to errors, and to present typical data for an assessment protocol. METHODS: A 5-bar, 2-degree of freedom linkage was used to model the geometry of the crank, pedal, and lower extremity. Two-degree force transducers at the pedal were used to calculate center of pressure and force applied at the foot. A Newton-Euler inverse dynamic model was used to calculate net joint torques and powers bilaterally of the ankle, knee, and hip. Ten subjects performed a high velocity evaluation protocol which served as the control. Error sensitivity was determined by adding instrumental error, hip translation, and segmental length errors to the collected data and comparing the outcome to the control. RESULTS: All variables associated with instrumental error had mean errors under 4%. Mean errors associated with violations of the fixed hip assumption were under 15% for all variables. Mean errors associated with anthropometric measures were divided into two types: relative error (overall length unchanged, ratios of segments changed) and absolute (overall length changed, ratios of segment lengths unchanged). Relative anthropometric mean errors were under 5%. Absolute anthropometric mean errors were under 12%. CONCLUSION: The Omnikinetic is a new tool for bilateral lower extremity evaluation that enables the whole lower extremity to be evaluated at the joint level. Instrumental accuracy was excellent. The instrument was most sensitive to violations of the fixed hip position assumption over the last 20 degrees of knee extension.

Adult↗
PubMed1993

Methodological issues in surveying older persons concerning drug use.

Despite beliefs that surveys involving older persons are less valid than those with other groups (due to memory loss, etc.), empirical verifications do not support this. Certain factors related to reduced validity must be considered (e.g., little education) and the confounding factors of cohort and time of measurement must be evaluated. Persons presumably suffering from dementia and institutional residents may be needlessly excluded. Methods suggested for improving validity include: sampling techniques, proxy respondents, administration and instrumentation, and interviewer variables. It is important to cross-validate data from surveys by using several concurrent methods. Instruments developed with younger subjects may be inappropriate or invalid with elders.

Aged↗
PubMed2000

The effects of emotion-oriented approaches in the care for persons suffering from dementia: a review of the literature.

OBJECTIVE: This article presents an overview of the results of intervention studies in various emotion-oriented approaches in the care for people suffering from dementia. Recommendations are made with regard to clinical practice and future research. DATA SOURCES: We searched for references (1990-99) in several bibliographical databases, i.e. Medline, PsycLit, Embase, Sociofile and Current Contents. The terms 'dementia' and 'Alzheimer's disease' were linked separately to the search terms: emotion-oriented, validation (therapy), sensory integration/sensory stimulation/snoezelen, simulated presence therapy and reminiscence (therapy)/life-review. Based on references in the articles found, other publications were traced. STUDY SELECTION: We started from the 'emotion-oriented' approaches used in 24-hour care distinguished by the American Psychiatric Association (1997) i.e. validation, sensory stimulation/integration, simulated presence therapy and reminiscence. We selected research articles that describe intervention, design, measuring instruments and results. DATA EXTRACTION: The articles were analyzed with regard to research group, setting, design, effect variables, intervention, measuring instruments, statistical analyses and results. DATA SYNTHESIS: It is shown that mainly positive results (including increased social interaction and decrease of behavior problems) are achieved with these emotion-oriented approaches. Unfortunately many studies have methodological limitations and are done independently, which makes comparison difficult. CONCLUSIONS: Despite the limited cogency of the studies we traced, the results are promising. Emotion-oriented care approaches offer the opportunity to tailor the care to the individual needs of dementing elderly and can be complemented with other psychosocial approaches (e.g. psychomotor therapy and music therapy) when necessary. The challenge for the care sector is to develop guidelines to determine which approach should be applied to whom and when. Scientific research can contribute by examining which emotion-oriented approaches, possibly in combination with each other or with psychosocial therapies, effect an increase in the well-being and improve functioning in which patients.

Aged↗
PubMed1991

A practical approach to content validation.

Often researchers are unable to find instruments to estimate variables they want to investigate. Once the variable of interest has been defined and operationalized, demonstrating content validity is the next step in the instrument development process. It requires that experts confirm that the operational definitions created are congruent with the universe of the theoretical definition of the concept. Grounded in appropriate standards and psychometric theory, the process of content validation is explored. Helpful suggestions are provided for the development of a form, the selection of experts, and the collection and analysis of data. The guidelines and examples presented offer a set of blueprints to assist the nurse researcher with a practical approach to the content validation process.

Delphi Technique↗
PubMed2005

Using anovaginal distance at the beginning of labor to predict the likelihood of instrumental delivery.

OBJECTIVE: To investigate whether anovaginal distance in parturients has an impact on the instrumental delivery rate. STUDY DESIGN: In this study with prospective data collection and a convenience sample, 400 parturients planning for vaginal delivery at term with a singleton fetus in vertex presentation were enrolled. Anovaginal distance was measured in the lithotomy position during the latent phase of labor or early first stage. This distance is thought to reflect the angle of inclination of the birth canal axis. RESULTS: At the cutoff point of 25 mm for anovaginal distance, the odds ratio for instrumental delivery was 2.5 (95% CI 1.48-6.6, p<0.05). A final model of instrumental delivery, controlling for various confounding variables, correctly predicted 91.38% of the instrumental deliveries (p<0.0001). The variables anovaginal distance >25 mm (OR 2.9, 95% CI 1.2-6.7, p=0.01), parity (OR 0.54, 95% CI 0.29-0.99, p=0.046) and duration of second stage of labor (OR 1.01, 95% CI 1.004-1.01, p=0.001) significantly contributed to the prediction of instrumental delivery after controlling for the other parameters. CONCLUSION: Women with an anovaginal distance of >25 mm at the beginning of labor was 2.5 more likely to undergo instrumental delivery than were women with an anovaginal distance of <25 mm.

Adult↗
PubMed1992

Introduction to instrument development for postanesthesia studies.

An important aspect of any research project is the selection of the instrument for which a "fit" exists between what is to be studied and the subjects. Physiological instruments are developed to objectively measure specific variables, such as temperature. Psychological instruments are usually developed to subjectively measure specific variables; however, there may not be a fit if the researcher used a paper-and-pencil instrument developed to measure anxiety in psychiatric patients to measure anxiety in the sedated, postanesthesia patient. An introduction to instrument development is presented including defining instruments, deciding what phenomena to measure and how to measure them, locating existing instruments, deciding when to develop an instrument, and identifying implications that arise from the use of inappropriate instruments.

Clinical Nursing Research↗
PubMed2001

Correlates of insight in serious mental illness.

This study extends research into insight by examining its relationship to a variety of demographic, clinical, neurocognitive, and psychosocial variables among a broad diagnostic sample of 211 adults with serious mental illness. Participants completed a full battery of instruments measuring these variables. Results support a relationship between ratings of poor insight and a psychotic (vs. mood) diagnosis, increased psychiatric symptoms, poorer social skills, and negative medication attitudes. Minorities and those with a substance abuse diagnosis were also more likely to be rated as having poor insight. No relationship was found between level of insight and age, gender, education level, neurocognitive deficits, hospitalization history, size of one's social network, or quality of life measures. Results are discussed in the context of improving the measurement and assessment of insight, conceptualizing interventions aimed at addressing level of insight, and improving outcomes for patients with severe and persistent mental illness. Findings also support a need for continued investigation of how mental illness is understood, experienced, and expressed across diverse groups of people living with mental illness.

Adult↗
PubMed2002

The use of an infrared eyetracker to measure fixation stability.

PURPOSE: To assess fixation stability in patients, a scanning laser ophthalmoscope (SLO) has typically been required. Disadvantages of this technique include the need for a fixed viewing distance and rigid head support. Some modern infrared eyetrackers do not have these constraints. The purpose of this study was to compare fixation stability measurements made with these instruments. METHODS: Normal subjects were asked to fixate a 2.5 degrees high cross while fixation was measured with a SLO and an infrared eyetracker. Bivariate contour ellipse areas were calculated. RESULTS: There was a linear relationship between the bivariate contour ellipse areas measured using each instrument. Bivariate contour ellipse areas returned from the eyetracker were larger. There was no difference in test-retest variability between the instruments. CONCLUSIONS: The eyetracker indicates fixation to be less stable than the SLO does, perhaps because of eye movements to compensate for small head movements. Our eyetracker can be used to analyze fixation when viewing images at any distance, without the need for head immobilization. The eyetracker and the SLO complement each other in the investigation of visual behavior.

Adult↗
PubMed1992

Isolated L4-L5 fusions using the variable screw placement system: unilateral versus bilateral.

Thirty-six patients were retrospectively followed an average of 25.1 months to evaluate the relative effectiveness of unilateral (16 patients) versus bilateral (20 patients) variable screw placement (VSP) instrumentation in isolate L4-L5 fusions. Demographic variables and preoperative diagnoses were similar between treatment groups. Outcome was assessed primarily through evaluation of plain roentgenograms and self-report questionnaires. Use of VSP instrumentation at the L4-L5 level with autogenous posterolateral grafting achieved a successful fusion rate of 97% with minimal complications. Fusion results with unilateral instrumentation were nearly identical to those of bilateral; in both cases, results were better than most historical controls for noninstrumented fusions in situ. Clinical outcome, as obtained through standardized measurement techniques of pain and function, demonstrated 69% excellent and good results. Clinical outcome was similar between treatment groups yet was not significantly related to the fusion status obtained at follow-up.

Adult↗
PubMed1991

[A different approach to perceptive phenomena in 250 0-5-year old children].

In this work there is a comparison between the different perceptions that a child can get from the dental instruments. The perception of dental instruments influences in a determinative way during dental attention. The sample consisted in the selection of 250 children whose ages ranges from 0 to 5 years. It was determined that age and experience influence in the perception of the objects as well as the different dental instruments used as variables.

Age Factors↗