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PubMed1989

Use of ethnographic research for instrument development in a case-control study of immunization use in Haiti.

A rapid ethnographic assessment of barriers to health service utilization was conducted to identify maternal factors predicting use of child immunizations in Haiti. Methods included four focus group interviews, four natural group interviews, individual interviews with 14 health care providers and participant observation at vaccination posts. Analysis of qualitative data identified five categories of maternal factors associated with immunization use: competing priorities, low motivation, socioeconomic constraints, perceived accessibility of services, fears about health or social consequences and knowledge and folk beliefs related to vaccines. Selected variables among these factors were incorporated into a survey instrument designed to compare mothers of completely vaccinated children (cases) with mothers of incompletely vaccinated children (controls). The questionnaire was administered to 299 randomly selected mothers (217 cases, 82 controls). Bivariate and multivariate analyses found that of the factors identified through ethnographic research, only vaccine-related knowledge was significantly associated with immunization status. The utility and constraints of using ethnographic research for instrument development in epidemiological studies are discussed.

Case-Control Studies↗
PubMed1992

Clinical versus instrumented knee testing on autopsy specimens.

The accuracy, reliability, and reproducibility of the Genucom Knee Analysis System and Knee Signature System (KSS) for anteroposterior knee laxity evaluations were compared. The devices detected the same relative change in laxity between normal and anterior cruciate ligament-deficient specimens during Lachman and drawer testing; however, the absolute values differed. In a clinical study, two examiners performed three independent Lachman and drawer tests using the Genucom, KSS, and a subjective clinical examination on ten patients. The Genucom demonstrated interexaminer differences during the Lachman test. The clinical examination proved to be more reliable than either instrumented device for both Lachman and drawer testing. The intraexaminer variability of the Genucom and KSS was large, with the average 95% confidence limits about the mean for the Genucom and KSS equal to +/- 4.2 and +/- 2.8 mm, respectively. These findings question the accuracy, reliability, and reproducibility of the instrumented methods.

Adolescent↗
PubMedDate not supplied

Determining the food irradiation beliefs of community nutrition educators: do beliefs influence educational outreach?

OBJECTIVE: To develop an instrument to measure the food irradiation beliefs of community nutrition educators and to determine the influence of those beliefs on food irradiation educational outreach. DESIGN: Survey development, cross-sectional telephone survey. SETTING: Cooperative Extension Program. PARTICIPANTS: All Family and Consumer Sciences (FCS) county extension agents serving in the most populated counties in Texas (n = 134, response rate = 99%). These participants may not be representative of all FCS extension agents. VARIABLES MEASURED: Food irradiation beliefs and educational outreach as well as selected demographic variables. ANALYSIS: To determine validity and reliability of the instrument, factor analysis and Cronbach's alpha were conducted, respectively. To determine if food irradiation beliefs influenced food irradiation educational outreach, logistic and multiple regression analyses were conducted, with significance set at P < .05. RESULTS: The instrument had adequate reliability; two belief scales were identified through factor analysis, referred to as Safety Beliefs and Understanding Beliefs. Additionally, regression analysis suggested that educators' beliefs about food irradiation influenced the amount of food irradiation education they provided. CONCLUSIONS AND IMPLICATIONS: Results suggest that educators' beliefs about the safety and their understanding of food irradiation are predictors of the educational outreach they provide about it, indicating the potential value of professional development regarding food irradiation.

Community Health Services↗
PubMed1998

Decision-making models in different fields of nursing.

The purpose of this study was to identify the decision-making models used by nurses in different fields of nursing and to find out which variables explain the use of those models. The instrument for the project was developed on the basis of existing decision-making theories and earlier studies on nurses' decision making. The sample consisted of 483 Finnish nurses from five fields of nursing: long-term care, short-term medical-surgical care, critical care, health care, and psychiatric care. The statistical analyses consisted of factor analysis, factor scores, and correspondence analysis. Five different models of nursing decision making were identified. The nature of the nursing task and the nursing context showed associations with decision making on all models. The structure of knowledge and nurses' practical experience did not provide an explanation for nurses' decision making on any model.

Critical Care↗
PubMed1981

The effects of nursing education on job effectiveness: an overview of the literature.

An overview of the published studies on the effectiveness of a nursing education as it relates to job performance is presented. Selected literature is reviewed and divided into three areas of study: competency, performance, and quality of care. The literature revealed contradictory evidence on the value of baccalaureate nursing education. More important, the review demonstrates a lack of rigorous research in this area. Suggested research directions include the measurement of individual performance rather than the perception of group performance, the development of better instruments, and control of the setting and individual variables that affect job performance. It is recommended that nursing effectiveness be defined in terms of both patient outcomes and nurse performance.

Clinical Competence↗
PubMed2000

Measurement of the Low-Frequency Dielectric Properties of Colloidal Suspensions: Comparison between Different Methods.

A careful analysis of the main factors that affect the low-frequency dielectric measurements of conducting liquid samples is carried out. The influence of the type of the measurement cell, the calibration method, and the type of the instrument used, on the spectra obtained using the variable electrode spacing technique, is investigated. Permittivity and conductivity measurements in the 10 Hz to 10 MHz range are reported for low (sigma approximately 0.01 S/m) and high (sigma approximately 0.7 S/m) conductivity samples, both electrolyte solutions and polystyrene particle suspensions. Two measurement cells are evaluated: one made of glass currently used at Granada and the other made of acrylic currently used at Tucumán. Two calibration methods, the classical Short/Open correction and the quadrupolar technique (similar to the Short/Open/Load correction), are contrasted, and two impedance analyzers, the HP 4284 A and the HP 4192 A, are compared. Copyright 2000 Academic Press.

Journal Article↗
PubMed1984

The gene in search of an identity.

The concept of the difference between the potential for a trait and the trait proper, i.e., between the genotype and the phenotype, became clear only during the first decade of the century, mainly through the work of Johannsen. Although Johannsen insisted on that the terms he coined were only helpful devices to organize data about heredity, it is obvious that they were bound from the beginning to the hypothesis that there was "something" in the gametes that could be rendered to analysis as discrete units. These units were the genes. This reductionist yet materially non-committed attitude has been developed into what I called instrumental-reductionism: the genes were hypothetical constructs that were accepted "as if" they were real entities. The research program developed on such a concept was very successful, not least because this instrumental approach allowed maximum flexibility in the attachment of meaning of the genes. While most geneticists accepted one or another position of this flexible concept, others took more extreme positions. At the one extreme end of the conceptual continuum was the realist approach that argued that genes were discrete, measurable, material particles, and on the other end, the claim that the attempts to identify discrete units only led to hyperatomism of a holistic view appropriate to heredity. The acceptance of the gene as a material and discrete unit, in the beginning of 1950s, opened the way to a deeper level of conceptualizing both its structure ("cistron-recon-muton") and function ("one gene--one enzyme"). The discovery of the structure of DNA finally offered a chemical-physical explanation to the geneticist's requirements of a material gene. Thus, within less than 20 years the gene has been established as a "sharply limited segment of the linear structure" that is involved in the structure of a product or its regulation. However, with turning of much of the attention to the eucaryotic DNA, it was necessary to accommodate the gene to an increasing flood of findings that did not tally with its concept as a discrete material unit. Without much heart-seeking among geneticists, the gene regained its role as an instrumental unit, or even as just an intervening variable, "a quantity obtained by specified manipulation of the values of empirical variables".(ABSTRACT TRUNCATED AT 400 WORDS)

DNA↗
PubMed1990

Real-time system for robust spectral parameter estimation in Doppler signal analysis.

In assessing the level of stenosis in extracranial Doppler analysis, spectral analysis has until now been used qualitatively, for the most part. Owing to the many variables affecting the measurements (mainly noise level and instrument setting made subjectively by the operator), the reliability of the inferences on the degree of stenosis is not clearly definable. Under such conditions the need arises for algorithms and systems that can estimate spectral parameters with a higher degree of accuracy, to verify whether reliable inferences can indeed by made or if this technique is only a qualitative one. In the paper a real-time spectral analysis system is described. The system relies on a new spectral estimation algorithm which gives estimates with good robustness with respect to noise. Moreover, a clear measurement procedure which eliminates the many subjective factors affecting the estimates has also been proposed and used. The system has been evaluated with simulated signals and in clinical trials and has shown better performance than the commonly used commercial analysers.

Adult↗
PubMed1976

Evaluation of the accuracy of a new ultrasonic fetal heart rate monitor.

An indirect Doppler fetal monitoring system has been developed and validated by computer comparison of simultaneous fetal heart rate (FHR) with Doppler and scalp ECG of high-risk patients during labor. The difference in measurement of FHR averaged 0.3 b.p.m., and 93 per cent of the Doppler FHR measures were within 10 b.p.m. of the ECG FHR. If interinstrument difference is discounted, 96 per cent were within 10 b.p.m. All types of decelerations and variability were well approximated. Doppler FHR from the instrument described may be relied upon as valid clinical information and may be obtained from over 90 per cent of labor patients with 93 per cent accuracy.

Doppler Effect↗
PubMed1993

Power spectrum analysis of the fetal heart rate during noradrenaline infusion and acute hypoxemia in the chronic fetal lamb preparation.

In a chronically instrumented fetal lamb the effect on heart rate variability of noradrenaline as well as hypoxemia is studied by the use of power spectral analysis. Subsequent to both noradrenaline infusion and hypoxemia the very low frequency components of the variability are markedly decreased as compared with control conditions. After hypoxemia also a high frequency peak appears in the spectrum.

Acute Disease↗
PubMed1996

Pain management knowledge, attitudes and clinical practice: the impact of nurses' characteristics and education.

This study examined the knowledge, attitudes, and clinical practice of registered nurses (N = 120) regarding pain management. Data were collected from nine varied clinical units in a large, university-affiliated, teaching hospital in an urban area of the Northeast. Demographic information was also collected to explore the relationship between nurses' characteristics, including previous pain education, clinical experience, area of clinical practice, and other variables, and knowledge, attitudes, and clinical practice. Three instruments were used in the study: (a) the Pain Management: Nurses' Knowledge and Attitude Survey; (b) a 12-item demographic questionnaire; and (c) a Pain Audit Tool (PAT) to gather data regarding pain assessment, documentation, and treatment practices from charts. Mean scores from the nursing knowledge and attitudes survey on pain revealed knowledge deficits and inconsistent responses in many areas related to pain management (mean, 62%; range, 41%-90%). The top two nurse-ranked barriers to pain management were related to patient reluctance to report pain and to take opioids for pain relief. Demographic data revealed that education about pain was most inadequate in the following areas: nonpharmacological interventions to relieve pain, the difference between acute and chronic pain, and the anatomy and physiology of pain. Chart audits with the Pain Audit Tool revealed that 76% of the charts (N = 82) lacked documentation of the use of a patient self-rating tool by nurses to assess pain, despite a high reported use (76%) of such a self-rating tool. Adjunct medications were ordered with some consistency, but appeared to be underutilized. This was especially true of nonsteroidal anti-inflammatory agents (mean use, 1%). Ninety percent of the charts had no documentation of the use of nonpharmacological interventions to relieve pain. Although this clinical setting has policies and resources in place regarding the management of pain, it would appear that they are not optimal. Practical recommendations are presented for increasing nurses' knowledge about pain management; improving the quality and the consistency of the assessment, documentation and treatment of pain; and disseminating pain management information.

Attitude of Health Personnel↗
PubMedDate not supplied

The influence of lifestyle on cardiovascular risk factors. Analysis using a neural network.

The cardiovascular pathologies are the most common causes of death in the elderly patient. To single out the main risk factors in order to effectively prevent the onset of the disease, the authors experimented a special computerized tool, the neural network, that works out a mathematical relation that can obtain certain data (defined as output) as a function of other data (defined as input). Data were processed from a sample of 276 subjects of both sexes aged 26-69 years old. The output data were: high/low cholesterolemia, HDL cholesterol, triglyceridemia with respect to an established cut-off; the input data were: sex, age, build, weight, married/single, number of children, number of cigarettes smoked/day, amount of wine and number of cups of coffee. We conclude that: (i) a relationship exists, deduced from a neural network, between a set of input variables and a dichotomous output variable; (ii) this relationship can be expressed as a mathematical function; (iii) a neural network, having learned the data on a sufficiently large population, can provide valid predictive data for a single individual with a high probability (up to 93.33%) that the response it gives is correct. In this study, such a result is found for two of the three cardiovascular risk indicators considered (cholesterol and triglycerides); (iv) the repetition of the neural network analysis of the cases in question after a "pruning" operation provided a somewhat less good performance; (v) a statistical analysis conducted on those same cases has confirmed the existence of a strong relationship between the input and the output variables. Therefore the neural network is a valid instrument for providing predictive in a single subject on cardiovascular pathology risks.

Adult↗
PubMed2003

Lesion of the common peroneal nerve during arthroscopy.

Arthroscopic knee surgery has been well accepted worldwide and has become an important part of orthopaedic surgery. The use of arthroscopy has reduced the duration of hospitalization, overall costs, and time required for the patient to return to sports activities or work. However, because of the closed nature of the procedure and proximity of neurovascular structures to instruments, substantial risk of injuries exists. Significant anatomic variability in the nerve course has not been reported in previous literature as a cause of a knee arthroscopy complication. We present a case of complete transection of an unusually located common peroneal nerve during a knee arthroscopy for lateral meniscal repair in a 22-year-old football player.

Adult↗
PubMed2005

A multiresidue analytical method using solid-phase extraction and high-pressure liquid chromatography tandem mass spectrometry to measure pharmaceuticals of different therapeutic classes in urban wastewaters.

An analytical method with two extraction steps has been developed and validated for the simultaneous determination of 30 pharmaceuticals belonging to various therapeutic categories in urban wastewater. The aim was to boost the little available information on drugs' fates in sewage treatment plants (STPs) and in the receiving surface water. Aqueous samples were divided into two aliquots, each extracted by a different solid-phase extraction (SPE) method and analysed by reversed-phase liquid chromatography tandem mass spectrometry (HPLC-MS-MS). Recoveries of the pharmaceuticals were mostly greater than 70% and the overall variability of the method was below 8%. The instrumental quantification limit (IQL) varied between 30 and 400 pg injected, and the limits of quantification (LOQ) were in the low ng/L range. Nineteen pharmaceuticals were detected in concentrations between 0.5 and 2000 ng/L in effluents collected from several STPs in Italy. Atenolol, ciprofloxacin, furosemide, hydrochlorothiazide, ofloxacin, ranitidine and sulphamethoxazole were the most abundant compounds. The present analytical method was useful to check for pharmaceuticals in various Italian STPs and to identify the most abundant compounds.

Chromatography, High Pressure Liquid↗
PubMed2006

Determination of pharmaceuticals of various therapeutic classes by solid-phase extraction and liquid chromatography-tandem mass spectrometry analysis in hospital effluent wastewaters.

A multi-residue analytical method has been developed and validated for determining a selection of 16 pharmaceuticals: the anti-epileptic carbamazepine, seven analgesic/anti-inflammatory drugs (mefenamic acid, indomethacine, ibuprofen, naproxen, diclofenac, ketorolac and acetaminophen), the analgesic opiate codeine, two antidepressants (fluoxetine and paroxetine), beta-blockers (atenolol and propranolol), antibiotic (trimethoprim, metronidazole, and erythromycin) and the anti-ulcer ranitidine in hospital effluent wastewaters. The method allows simultaneous extraction of the pharmaceuticals compounds by solid-phase extraction (SPE) using the Waters Oasis HLB at pH 7. The analytes were then identified and quantitatively determined by liquid chromatography-tandem mass spectrometry (LC-MS-MS) using multiple reaction monitoring (MRM). Recoveries of the pharmaceuticals were higher than 75%, with the exception of ranitidine (45%) and the overall variability of the method was below 9%. The instrumental detection limit (IDL) varied between 2 and 31 pg injected, the method detection limit (LOD) was between 7 and 47 ng/L in spiked hospital effluent. The precision of the method, calculated as relative standard deviation (RSD), ranged from 0.3 to 4.9%. A detail study off matrix effect is included in this work, regarding to signal suppression in these effluent wastewaters from a hospital complex samples. The developed analytical method was applied for preliminary data results in effluent wastewaters from a hospital.

Adrenergic beta-Antagonists↗
PubMed2004

Clinical predictors of admission status in first episode schizophrenia.

Having a diagnosis of schizophrenia is a risk factor for involuntary admission to psychiatric inpatient care, but we have a limited understanding of why some patients and not others require involuntary admission. We aimed to identify the predictors of involuntary admission in first episode schizophrenia. We used validated instruments to assess clinical and socio-demographic variables in all patients (n = 78) with first episode schizophrenia from a defined geographical area admitted to a Dublin psychiatric hospital over a 4-year period. Involuntary patients (n = 17) could not be distinguished from voluntary patients (n = 61) on the basis of age, gender, living status, marital status, drug abuse or duration of untreated psychosis. Neither positive nor negative symptoms were useful predictors of admission status. Lack of insight was a strong predictor of involuntary status.

Adult↗
PubMed2006

A prospective evaluation of adherence to medication in first episode schizophrenia.

The aim of this study was to identify the features of first episode schizophrenia that predict adherence antipsychotic medication at six-month follow-up. We used validated instruments to assess clinical and socio-demographic variables in all patients with first episode schizophrenia from a defined geographical area admitted to a Dublin psychiatric hospital over a four-year period (N=100). At six-month follow-up (N=60) we assessed adherence to medication using the Compliance Interview. One third of patients with schizophrenia were non-adherent with medication within six months of their first episode of illness. High levels of positive symptoms at baseline, lack of insight at baseline, alcohol misuse at baseline and previous drug misuse predict non-adherence. These results indicate that an identifiable subgroup of patients with first episode schizophrenia is at high risk of early non-adherence to medication. While high positive symptom scores pre-date and predict non-adherence in most patients, reduced insight is the best predictor of non-adherence in patients who do not misuse alcohol or other drugs.

Adult↗
PubMed2005

Operator learning effect and interoperator reproducibility of the scanning laser polarimeter with variable corneal compensation.

PURPOSE: To ascertain operator learning effect, and to quantify the interoperator reproducibility, using the newly introduced GDx VCC (variable corneal compensator) scanning laser polarimeter. DESIGN: Prospective instrument validation study. PARTICIPANTS: Three operators with no prior experience in operating the GDx VCC examined one randomly chosen eye of each of 30 randomly ordered subjects (15 glaucoma patients and 15 normal subjects). METHODS: Each study eye was scanned by the 3 operators in a random sequence during a single session. Five GDx parameters were analyzed: TSNIT (temporal, superior, nasal, inferior, temporal) Average, TSNIT Standard Deviation (SD), Superior Average, Inferior Average, and Nerve Fiber Indicator (NFI). MAIN OUTCOME MEASURES: Retinal nerve fiber layer (RNFL) thickness GDx parameters across operators. RESULTS: A learning effect was not found for any of the operators for any of the 5 GDx parameters studied. Reproducibility for each GDx parameter was measured as the mean SD value of the measurements taken by the 3 operators. Interoperator reproducibilities for normal and glaucomatous eyes, respectively, were 0.8 and 1.6 microm (TSNIT Average), 1.7 and 2.2 microm (Superior Average), 1.6 and 2.7 microm (Inferior Average), 1.3 and 1.7 microm (TSNIT SD), and 1.4 and 4.6 microm (NFI). The data obtained by each operator were highly correlated with those of the other 2 operators. CONCLUSIONS: With the commercially available GDx VCC, a learning effect was not found for 3 novice operators. In addition, RNFL measurements seem highly reproducible across operators.

Adult↗