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PubMed2006

Factors associated with computer literacy among nurses.

Nowadays, many hospitals have adopted information technology (IT) to help nurses in their practice; therefore, computers have become critical instruments for nurses. Many researchers have studied what information literacy or computer competencies a nurse should possess, but less research has focused on the types of factors associated with computer literacy. The purpose of this study was to discover which variables influence the computer literacy of nurses. The questionnaire was the instrument for data collection. The respondents were 180 nurses in Taiwan. The results of this study revealed that computer experience of nurses and personal innovation in IT were both factors associated with computer literacy and computer anxiety. The findings could assist nursing managers to screen computer-literate nurses and course designers in nursing school or hospitals to add more practical trainings in courses.

Adult↗

PubMedDate not supplied

[Factors associated with health related quality of life in patients undergoing renal replacement therapy].

The aim of this study was to investigate the sociodemographic and clinical variables which influence health-relate quality of life (HRQOL) of patients on renal replacement therapy (RRT). A cross-sectional study was carried out with a sample including all patients on hemodialysis (n = 170) and transplant patients (n = 210) of our region. The HRQOL assessment instruments used in this study were: the Spanish versions of the sickness impact profile (SIP) and the SF-36 health survey (SF-36). Sociodemographic and clinical data (including age at start of RRT, age at the interview, gender, hospital, socioeconomic level, educational level, living conditions, inclusion in transplant waiting list, renal disease diagnosis, time in any RRT, hemoglobin, hematocrit, serum urea, creatinine, proteins and albumin, hospital admissions and length of hospital stay during last year), a comorbidity index and the Karnofsky performance scale score step. To investigate which studied variables had independent influence over the HRQOL measures, logistic regression method was employed in the case of the SF-36, and multiple regression, in the case of the SIP. A model was adjusted step by step in each RRT method (hemodialysis and transplantation) for each dimension of the PCE (physical dimension, psychosocial dimension and total score), and for each component summary score of the SF-36 (physical and mental component summary). In patients on hemodialysis, variables associated with better HRQOL were: higher age, female gender, higher educational level, and better functional status; and variables associated with worse HRQOL were: higher number of hospital admissions, and higher comorbidity index. In transplant patients, variables associated with better HRQOL were: higher age and higher functional status; and variables associated with worse HRQOL were: longer time on dialysis before transplant, longer time with functioning transplant, and higher comorbidity index. Despite the independent influence on the HRQOL demonstrated for some of the studied variables, it seems that HRQOL assessment instruments scores may mainly depend on other non-studied variables, and it may be that these instruments evaluate other aspects of the patients which have not been taken into account until now.

Aged↗

PubMed1997

[Investigation methods in clinical cardiology. IV. Clinical measurements in cardiology: validity and errors of measurements].

Measurements represent an essential part of clinical activity. Very often, however, relevant disagreement in clinical measurements becomes apparent. The sources of this variability are the subjects (patients) that are measured, the measurement instrument itself, and the observer. The assessment of the quality of measurement usually relies on the evaluation of its reproducibility and its validity. The reproducibility is basically measured as the inter-observer concordance, the intra-observer concordance, and the test-retest concordance. The specific parameter used to its quantification (intra-class correlation coefficient, kappa index, graphic methods, etc.) depend on the kind of variable to be measured. The validity of the measurement is the degree to which the measurement is really measuring what we think it should. If an acceptable standard is available, then so called criterion validity is usually assessed. Otherwise the validity should be assessed by other ways that use subjective criteria (content validity and face validity) or empirical criteria (construct validity).

Cardiology↗

PubMed1994

Testing the measurement properties of risk assessment instruments in child protective services.

This study examined a population of children alleged to be at risk of abuse and the adult allegedly abusing the child for the purpose of identifying variables that were predictive of the child's risk of being abused. The study population consisted of 72 Brooklyn, New York children and the alleged adult abuser. These cases were investigated in the Child Protective Services office in Bedford-Stuyvesant by 12 workers who volunteered to participate in the research effort. The worker assigned to a case filled out the standard New York City case recording instrument (called the Child Protective Services Review Document, CPSRD for short), the Magura-Moses Child Well-Being Scales, and the Beck and Jones List of Problems and Conditions. In addition, the worker also evaluated the degree of risk of abuse that the child was exposed to from the alleged abuser using a supplemental scale created for this study. Our hypotheses were that variables from each of the instruments would be predictive of the case decision-making by protective service workers regarding the abuse to which a child was exposed, that the data from the Magura-Moses scales would have predictive value for a minority population, and that the data from the CPSRD would reflect unique dimensions of this population. The data from the 72 cases supported each of these hypotheses.

Adaptation, Psychological↗

PubMedDate not supplied

Assessment of disordered eating in females: instrument validation.

The purpose of this study was to validate an instrument capable of assessing 10 dimensions related to disordered eating and weight control behaviors. All subjects were female and ranged in age from 14 to 40. Of these females 68 were bulimics, 12 were compulsive eaters, and 24 eating disorders. The Disordered Eating and Weight Control Instrument (DEWCI) was administered. Differences between the groups were investigated by constructing three dummy variables contrasting the groups, correlating the scales with the dummy variables, and determining which correlations were significant. Eight of the DEWCI scales significantly (p less than .005) differentiated between the three groups. This instrument may therefore have utility for use with female populations.

Adult↗

PubMed1991

Health status (arthritis impact) in children with chronic rheumatic diseases. Current measurement issues and an approach to instrument design.

Arthritis outcome measures in adults have evolved from biologic "disease activity," to observations of motor/movement based "functional status," to assessment of "health status." This monograph suggests a framework for developing a pediatric arthritis health status (impact) instrument in which measurable global outcome dimensions include psychological, social, ADL, pain, school, family, behavioral, and developmental variables. Physical and laboratory parameters of inflammation/disease activity are not part of either functional status or arthritis impact, but rather perhaps the most important predictor variable of outcome. Juvenile rheumatoid arthritis (JRA) is a prototypic chronic disease for development of a health status instrument for children. Prior obstacles have been (a) that systemic, polyarticular, and pauciarticular JRA appear to have very different amounts of impact on health status; and (b) although juvenile arthritis has proven a useful term for medical and public education, its value as a study entry criterion for functional status instrument development is limited. Any new pediatric arthritis impact instrument must fulfill five criteria: enable quantification; demonstrate reliability, validity, and precision; and specify data collection procedures. Important design issues include (a) developing a self-report format for children, (b) ensuring generalizability across age groups, and (c) the parent as proxy in most patient-related dialogue and interventions. Instrument elements could come from 8-10 adult and pediatric health/functional status instruments already in use. By 10 years of age, children can provide much independent information. Whether global assessments by patient, parent, and physician should be included, or be a separate "gold standard," is not yet clear. The creation of better health status measures is an important and formidable challenge for pediatric rheumatology.

Age Factors↗

PubMed1997

Retroperitoneal and intraperitoneal CO2 insufflation have markedly different cardiovascular effects.

Both retroperitoneoscopic and laparoscopic surgical approaches to kidney and adrenal gland have been reported but their cardiopulmonary pathophysiology has been incompletely characterized. To test the hypothesis that these approaches have markedly different impact on the circulatory and respiratory systems, we assessed at similar insufflation pressures alterations in cardiovascular and respiratory variables during retroperitoneal and intraperitoneal CO2 insufflation. Eighteen healthy, anesthetized (propofol, alfentanil, vecuronium), mechanically ventilated pigs were randomly instrumented for either retroperitoneoscopic (n = 9) or laparoscopic (n = 9) surgery. After CO2 insufflation cardiovascular and respiratory variables were measured at four cavity pressures (baseline, 10, 15, and 20 mmHg), while end-expiratory CO2 tension was maintained by adjusting tidal volume. Data were analyzed for both insufflation-pressure-dependent and group effects by one-way and two-way ANOVA for repeated measurements, respectively, followed by Newman-Keuls post hoc test (P < 0.05). Cardiac output, mean arterial, pulmonary artery, central venous, and femoral venous pressures increased significantly in both groups in an insufflation-pressure-dependent fashion. However, changes in cardiac output (P < 0.001), pulmonary artery (P < 0.007), central venous (P < 0.001), and iliac venous pressures (P < 0.001) for the same insufflation pressure were markedly and significantly greater with intraperitoneal than retroperitoneal CO2 insufflation. Most important, intraperitoneal unlike retroperitoneal insufflation induced a marked inferior vena caval pressure gradient (8.9 +/- 1.1 mmHg vs 1.0 +/- 0.5 mmHg, P < 0.00001). While both retroperitoneal and intraperitoneal CO2 insufflation required increased tidal volumes to adjust endtidal CO2 tension to baseline, intraperitoneal CO2 insufflation resulted in a significantly greater increase of mixed venous and arterial carbon dioxide tensions (P < 0.007) even at similar insufflation pressures. Furthermore, significantly greater peak airway pressures (P = 0.018) were required with intraperitoneal than with retroperitoneal insufflation to administer the same tidal volume, indicating a greater decrease in quasi-static compliance with intraperitoneal insufflation (P = 0.0436). Thus, (i) cardiovascular and respiratory changes are much less during retroperitoneal than intraperitoneal CO2 insufflation, even at the same insufflation pressures, and (ii) retroperitoneal CO2 insufflation unlike intraabdominal CO2 insufflation does not induce an inferior vena caval pressure gradient and hence does not appear to impair systemic lower body venous return up to insufflation pressures of 20 mmHg.

Animals↗

PubMed1998

Systemic lupus erythematosus in three ethnic groups: II. Features predictive of disease activity early in its course. LUMINA Study Group. Lupus in minority populations, nature versus nurture.

OBJECTIVE: To determine the factors associated with disease activity in patients with recent-onset (< or =5 years) systemic lupus erythematosus (SLE) who were of Hispanic, African-American, or Caucasian ethnicity. METHODS: Incident and prevalent cases of SLE, as defined by the American College of Rheumatology criteria for SLE, among the 3 ethnic groups were identified in Alabama (The University of Alabama at Birmingham) and Texas (The University of Texas-Houston Health Science Center and The University of Texas Medical Branch at Galveston). Variables from the sociodemographic, clinical, immunologic, immunogenetic, behavioral, and psychological domains were obtained using validated instruments. Disease activity was ascertained with the Systemic Lupus Activity Measure (SLAM). Stepwise domain regressions with SLAM score as the dependent variable were performed. Final ethnic-specific and overall regression models were obtained by entering variables that were retained in the domain regressions. RESULTS: SLAM scores at study entry were higher in the African Americans (mean +/- SD 12.6 +/- 6.9) and Hispanics (11.0 +/- 6.2) than in the Caucasians (8.5 +/- 3.7) (P < or = 0.001). The final overall regression model (R2 = 28%) for higher SLAM score included the following variables: African-American ethnicity, lack of private health insurance, abrupt disease onset, presence of anti-Ro antibodies, absence of HLA-DRB1*0301, higher levels of helplessness, and abnormal illness-related behaviors. CONCLUSION: Socioeconomic, immunologic, immunogenetic, behavioral, and psychological variables were all predictive of disease activity early in the course of SLE, irrespective of ethnic group. However, there remain ethnic group differences in disease activity that were not explained by these factors.

Adolescent↗

PubMed1979

Visual and automated differential leukocyte counts. A comparison study of three instruments.

The authors compared referee (senior author) microscopic counts, microscopic counts by several technologists, and counts obtained with two pattern-recognition leukocyte classifiers, (1) Larc and (2) Hematrak, and a cytochemical automated method for leukocyte counting, (3) Hermalog D, using samples from (1) a random patient population, (2) a selected abnormal patient population, and (3) healthy individuals. All instruments showed good accuracy and flagged abnormal results for review. Variability in pattern-recognition counts was found to be due mainly to the distribution of the cells on prepared blood smears. The Larc classifier was found to be very sensitive to minor alterations in the cytoplasm or nucleus, and rejected a number of slides. The Hemalog D showed the greatest precision. The method of preparation of slides would be a major decision factor in selecting one pattern-recognition instrument over another.

Adult↗

PubMed2001

Living musical instruments and inanimate body parts?

In the literature about category effects in semantic memory, body parts and musical instruments are often considered atypical, because in cases with a disproportionate impairment of living categories body parts are relatively spared, while musical instruments are often severely defective. In this study the performance of 57 subjects affected by diseases generally associated with lexical-semantic impairment, for the most part Alzheimer's disease and other forms of cortical degeneration, but also herpetic encephalitis and traumatic brain damage are analyzed. The subjects were given a picture naming task tapping eight categories: three living categories (animals, fruits and vegetables) and three non-living categories (tools, furniture and vehicles), plus body parts and musical instruments. On a preliminary analysis at the group level, body parts were the least impaired category and musical instruments the most severely impaired, the six living and non-living categories being intermediate. However, these differences disappeared after covariance for lexical frequency, name agreement and age of acquisition. The relationship between living categories, non-living categories, musical instruments and body parts was investigated by means of a Lisrel model of Confirmatory Factor Analysis. Two latent variables related to living and non-living categories respectively were defined, and it was found that both body parts and musical instruments were significantly related only with non-living categories. The results showed that the definition of the latent variable expressing the substrate of non-living categories was less satisfactory than that expressing the living categories. On this basis, the conclusions of this study appear statistically definite but their psychological interpretation is less straightforward.

Adolescent↗

PubMed1995

Factors affecting couples' adjustment to recurrent breast cancer.

The purpose of this study was to identify factors that affect the adjustment of women and their husbands to recurrent breast cancer and to examine the mutual effect that partners have on one another. An exploratory study was designed to determine the relationship between four predictor variables (support, uncertainty, symptom distress, hopelessness) and women's and husbands' adjustments. The sample consisted of 155 subjects; 81 women, who had a first recurrence of breast cancer, and 74 husbands. Multiple standardized instruments with established reliability and validity were used to measure the study variables. The independent variables were measured with the Social Support Questionnaire, the Mishel Uncertainty in Illness Scale, McCorkle Symptom Distress Scale and the Beck Hopelessness Scale. The dependent variable, psychosocial adjustment, was measured with the Brief Symptom Inventory and the Psychosocial Adjustment to Illness Scale. The results indicated that the independent variables accounted for 43% of the variance in women's distress and 32% of the variance in husbands' distress; they also explained 66% of the variance in women's role adjustment problems and 57% of the variance in husbands' role problems. Symptom distress and hopelessness accounted for the most variance in women's and husbands' levels of adjustment. A significant and positive relationship was found between women's and husbands' adjustment scores, indicating that partners have a mutual influence on one another. The findings suggest that there are multiple factors that influence couples' adjustment to recurrent breast cancer, and that these factors need to be taken into consideration when planning care for women and their partners.

Adaptation, Psychological↗

PubMedDate not supplied

Validation of tardive dyskinesia as measured on the Dyskinesia Identification System--Coldwater.

Identification and description of tardive dyskinesia have been hampered by the absence of systematic studies assessing the psychometric properties of existing instruments. The purpose of this study was to establish construct validation of one of these instruments, the Dyskinesia Identification System--Coldwater. Cross-sectional prevalence assessment data of 519 institutionalized mentally retarded persons were used. The 34 items of this instrument were subjected to exploratory factor analysis. A six-factor orthogonal solution was selected. Multiple regression analyses supported the established relationships of demographic variables, such as age and sex, with the tardive dyskinesia scores generated by the instrument.

Adolescent↗

PubMed2003

Cardiopulmonary, blood and peritoneal fluid alterations associated with abdominal insufflation of carbon dioxide in standing horses.

REASONS FOR PERFORMING STUDY: Abdominal insufflation is performed routinely during laparoscopy in horses to improve visualisation and facilitate instrument and visceral manipulations during surgery. It has been shown that high-pressure pneumoperitoneum with carbon dioxide (CO2) has deleterious cardiopulmonary effects in dorsally recumbent, mechanically ventilated, halothane-anaesthetised horses. There is no information on the effects of CO2 pneumoperitoneum on cardiopulmonary function and haematology, plasma chemistry and peritoneal fluid (PF) variables in standing sedated horses during laparoscopic surgery. OBJECTIVES: To determine the effects of high pressure CO2 pneumoperitoneum in standing sedated horses on cardiopulmonary function, blood gas, haematology, plasma chemistry and PF variables. METHODS: Six healthy, mature horses were sedated with an i.v. bolus of detomidine (0.02 mg/kg bwt) and butorphanol (0.02 mg/kg bwt) and instrumented to determine the changes in cardiopulmonary function, haematology, serum chemistry and PF values during and after pneumoperitoneum with CO2 to 15 mmHg pressure for standing laparoscopy. Each horse was assigned at random to either a standing left flank exploratory laparoscopy (LFL) with CO2 pneumoperitoneum or sham procedure (SLFL) without insufflation, and instrumented for measurement of cardiopulmonary variables. Each horse underwent a second procedure in crossover fashion one month later so that all 6 horses had both an LFL and SLFL performed. Cardiopulmonary variables and blood gas analyses were obtained 5 mins after sedation and every 15 mins during 60 mins baseline (BL), insufflation (15 mmHg) and desufflation. Haematology, serum chemistry analysis and PF analysis were performed at BL, insufflation and desufflation, and 24 h after the conclusion of each procedure. RESULTS: Significant decreases in heart rate, cardiac output and cardiac index and significant increases in mean right atrial pressure, systemic vascular resistance and pulmonary vascular resistance were recorded immediately after and during sedation in both groups of horses. Pneumoperitoneum with CO2 at 15 mmHg had no significant effect on cardiopulmonary function during surgery. There were no significant differences in blood gas, haematology or plasma chemistry values within or between groups at any time interval during the study. There was a significant increase in the PF total nucleated cell count 24 h following LFL compared to baseline values for LFL or SLFL at 24 h. There were no differences in PF protein concentrations within or between groups at any time interval. CONCLUSIONS: Pneumoperitoneum with CO2 during standing laparoscopy in healthy horses does not cause adverse alterations in cardiopulmonary, haematology or plasma chemistry variables, but does induce a mild inflammatory response within the peritoneal cavity. POTENTIAL RELEVANCE: High pressure (15 mmHg) pneumoperitoneum in standing sedated mature horses for laparoscopic surgery can be performed safely without any short-term or cumulative adverse effects on haemodynamic or cardiopulmonary function.

Animals↗

PubMed1994

Health status assessment in a hypertension section of an internal medicine clinic.

The authors obtained health status instrument information with the SF-36 and COOP charts distributed in random order (along with selected items from the Hypertension Technology of Patient Experience [TyPE] tool) to patients attending the hypertension section of an internal medicine clinic. The goal was to examine and compare potential associations of clinical, demographic, and/or treatment variables with SF-36/COOP health status scale variables in a nonuniversity urban clinic. One hundred fifty-eight pairs of health status instruments were returned (62% response rate). One hundred (64%) had a diagnosis of hypertension, 81 (51%) were males, 94 (60%) were older than 65 years, and 122 (78%) were white. Clinical, demographic, and treatment measurements were studied using regression analysis; the estimated regressions accounted for 4-32% of the variation in the COOP scales and 8-19% in the SF-36 scales. The number of coexisting diseases, gender, and diagnosis of hypertension were the most frequent significant variables associated with health status scale outcomes for each health status instrument. For most COOP and some SF-36 scales, there was a significant hypertension by gender interaction indicating that women with a hypertension diagnosis report better health status than women seen for other conditions; hypertension diagnosis had little effect on men's reported health status for most scales. Further study is necessary to confirm these results, yet the regression models developed in this study suggest that health status as assessed by these instruments is affected by multiple and not always obvious factors.

Aged↗

PubMed1989

Characterization of instrumentation and calibrators for quantitative microfluorometry for immunofluorescence tests.

The current method for measuring reagents for immunofluorescence microscopy involves a subjective evaluation of the endpoint (titer) with a negative or positive (1+ to 4+) scale. Variability is due to the biological constituents of the reagent, the observer, and the instrumentation. To have reliable methods for evaluation of performance of these products, we are developing a quantitative method that uses photometric measurements of microscopically observed epifluorescence of slide preparations. A computer-controlled microscope-photometer converts the light intensity into a voltage measurement. Our goal is to replace the subjective endpoint determination with an objective, quantitative method. The instrumentation and its operating characteristics are presented in this paper. Selected commercially available fluorescent materials were evaluated as calibrators for the instrumentation. These materials showed consistency in measurement and thus demonstrated their suitability for various levels of calibration. It is possible that they will prove useful as a reference standard for interlaboratory comparisons.

Cytophotometry↗

PubMed1989

Instrument reliability and validity: how much needs to be published?

Although the 20 studies reviewed from Heart & Lung are methodologically sound and quite sophisticated, just as in less well-designed research, the results of these studies are not able to rise above the quality of the instrumentation used and reported. Regardless of the actual quality of instrumentation used in a study, unless it is supported by at least minimum descriptive, reliability, and validity information, the data and results should not be assumed to have any merit. Only when the instrumentation is described in such a way that the consumer of the research knows what type(s) of instrumentation was used, how accurate it has been and was in this study, and the extent to which it measured the intended variables, should the results of research be given credence. A careful researcher would offer such instrumentation information and a wise consumer should accept no less.

Data Collection↗

PubMed1998

The role of purinergic and adrenergic transmitters of the sympathetic system in the control of arterial blood pressure variability.

Variability of mean arterial pressure (MAP) was examined in chronically instrumented, conscious, freely moving rats with pharmacologically altered efferent sympathetic influences on the cardiovascular system. MAP was recorded for 30 min beat-to-beat, using a computer under both control and experimental conditions: after administration of adrenoceptor antagonists (prazosin or phentolamine) or under P2X receptor inactivation produced either by desensitization with alpha, beta-methylene ATP or by PPADS blockade. Inhibition of adrenergic sympathetic effects on the cardiovascular system produced long-lasting and stable decrease in MAP. Prazosin did not modify MAP variability whereas phentolamine enhanced it. Under P2X receptor desensitization MAP decreased, the hypotensive effect being accompanied by a significant increase in MAP variability. A similar increase in MAP variability was observed after PPADS administration, while MAP level was not changed. Administration of PPADS in combination with phentolamine increased MAP variability more significantly than each of the drugs given separately. Changes in MAP variability under the various experimental conditions were not consistently correlated with changes in heart rate variability. We propose that ATP, being a mediator of sympathetic vasoconstriction, participates in baroreceptor-induced stabilization of MAP level.

Adenosine Triphosphate↗

PubMed2005

Selection of outcome assessment instruments for inpatients with severe and persistent mental illness.

The purpose of this article is to describe a procedure to assist in selecting outcome measures for inpatients treated at a state psychiatric hospital. The procedure combines evidence-based criteria from the literature, instruments shown to be sensitive to change in clinical trials, and the perspectives of a multidisciplinary team of researchers, administrators, providers, and patient advocates. Recent efficacy and effectiveness studies were used to identify recurrently used outcome instruments. A computerized search of more than 30 bibliographic databases, such as PsycINFO, MEDLINE, Social SciSearch, and ERIC, was conducted for articles published between 1990 and 2002. Comparisons of the most frequently used instruments were made on seven criteria proposed as best-practice indicators, including sensitivity to change and robust psychometrics. The sample produced 110 measures. Rater-completed instruments were represented more often than patient-completed ones. However, considerable variability across both methods was found on the criteria. The limited resources associated with publicly funded inpatient facilities led to a recommendation to select at least one rater-completed and one patient-completed instrument.

Brief Psychiatric Rating Scale↗