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PubMed1999

Psychosocial outcome assessments for use in cardiac rehabilitation service evaluation: a 10-year systematic review.

A variety of measures are currently used to assess psychosocial outcome (quality of life) in cardiac rehabilitation programmes. However, there is no consensus on the most appropriate instruments to use. Instruments that are not sufficiently responsive to change in cardiac populations are unsuitable as audit tools as they underrepresent the benefits of programme attendance. To identify the most responsive instruments in cardiac rehabilitation populations a systematic overview of studies for the 10-year period 1986-1995 was conducted. The following databases were searched: Medline, Psychlit, Cinahl and Sociofile and 32 relevant studies were identified. The effect size statistic (a comparison of the magnitude of change to the variability in baseline scores) was used to determine those instruments most responsive to change. The following instruments were identified as being responsive in more than one study: Beck Depression Inventory, Global Mood Scale, Health Complaints Checklist, Heart Patients Psychological Questionnaire and Speilberger State Anxiety Inventory. There is little consensus on psychosocial evaluation instrument use in the cardiac rehabilitation literature. A number of measures show significant potential for routine outcome assessment. Formal assessment of these instruments is recommended to inform final recommendations about instrument selection for audit and evaluation purposes in cardiac rehabilitation.

Cardiac Rehabilitation↗
PubMed1977

Analytical performance and comparability of the determination of cholesterol by 12 Lipid-Research Clinics.

Twelve Lipid-Research Clinic laboratories performed automated cholesterol analyses on four control-serum pools of known cholesterol concentration, using the Liebermann-Burchard reaction. The analyses were done during a two-year period, with the same standards, methodology, and quality-control procedures. Estimates of analytical bias, variability, and short- and long-term trends for each instrument and for the entire group of LRC instruments are presented. High accuracy, precision, and interlaboratory comparability were achieved through the rigorous standardization and control of the entire analytical procedure. The significance of these results for long-term collaborative studies is discussed. Individual laboratory biases averaged from 0.5 to 2.0% below Abell-Kendall reference values. Between-run variability was about equal to within-run variability and inter-laboratory variation was substantially less than intra-laboratory variation. The total standard deviation for all instruments was about 0.04 g/liter. Only 8-15% of this variation was due to differences between instruments. The between-instrument standard deviation ranged from 0.011 to 0.015 g/liter; the between-run, within-instrument standard deviation ranged from 0.023 to 0.030 g/liter; and within-run standard deviation ranged from 0.023 to 0.028 g/liter. The significance of the achieved results for long-term collaborative studies is discussed.

Cholesterol↗
PubMed2005

Determining the basic psychometric properties of the Greek KDQOL-SF.

The aim of this study was to determine the basic psychometric properties, i.e. reliability and validity, of the Greek version of the Kidney Disease Quality of Life Short Form (KDQOL-SF). The instrument was self-administered to a homogenous group of 665 end stage renal disease patients in 20 dialysis units throughout Greece and the overall response rate was 72.6%. Reliability was demonstrated by Cronbach's alpha exceeding the recommended minimum value of 0.70 in all, except one, scales. Tests of item-internal consistency, after correction for overlap, resulted in correlations between items and their hypothesized scales, which exceeded the 0.40 standard in 94.5% of the cases. Item discriminant validity tests indicated 100% scaling success for six out of eight generic and disease-targeted scales. Validity was supported by the confirmation of expected correlations between scales and the overall health-rating item included in the instrument and with sociodemographic and self-reported health variables. Multiple stepwise linear regression analysis demonstrated that all disease-targeted scales were important predictors of SF-36 general health scales and the variance explained ranged from 37% to 57%. Overall, the psychometric properties of the KDQOL-SF, resulting from this first-time administration of the instrument to a Greek dialysis population, were good and the disease targeted scales were informative and of high internal consistency reliability. Cross-sectional construct validity is demonstrated, despite the lack of external validity criteria based on clinical ratings of severity. The results support administering the Greek KDQOL-SF in studies evaluating dialysis therapy and contribute to transnational comparison of findings.

Aged↗
PubMed2007

Perceptions and competence in evidence-based medicine: Are surgeons getting better? A questionnaire survey of members of the Dutch Orthopaedic Association.

BACKGROUND: The Journal of Bone and Joint Surgery, American Volume (The Journal) recently initiated a section called "Evidence-Based Orthopaedics." Furthermore, a level-of-evidence rating is now used in The Journal to help readers in clinical decision-making. Little is known about whether this recent emphasis has influenced surgeons' perceptions about and competence in evidence-based medicine. Therefore, we examined perceptions and competence in evidence-based medicine among Dutch orthopaedic surgeons. METHODS: Members of the Dutch Orthopaedic Association were surveyed to examine their attitudes toward evidence-based medicine and their competence in evidence-based medicine. We evaluated competences using a newly developed instrument tailored to surgical practice. RESULTS: Of the 611 members, 367 surgeons (60%) responded. Orthopaedic surgeons welcomed evidence-based medicine. Practical evidence-based medicine resources were perceived as the best method to move from opinion-based or experience-based to evidence-based practice. Four variables were significantly and positively associated with the competence instrument: (1) a younger age, particularly between thirty-six and forty-five years (p = 0.007), (2) experience of less than ten years (p = 0.032), (3) having a PhD degree (p < 0.001), and (4) working in an academic or teaching setting (p = 0.004). The majority of the respondents were aware of The Journal's evidence-based medicine section (84%) and level-of-evidence ratings (65%), and 20% used The Journal's evidence-based medicine abstracts in clinical decision-making. This increased awareness of evidence-based medicine was also reflected in the frequent use of Cochrane reviews in clinical decision-making (27% of the respondents). Surgeons who used and those who were aware of but did not use The Journal's evidence-based medicine abstracts or Cochrane reviews in clinical decision-making had significantly higher competence instrument scores than those who were unaware of these resources (p = 0.03 and p < 0.001, respectively). CONCLUSIONS: Evidence-based medicine is welcomed by Dutch orthopaedic surgeons. The recent emphasis on evidence-based medicine is reflected in an increased awareness about The Journal's evidence-based medicine section, levels of evidence, and the largest evidence-based medicine resource: the Cochrane reviews. Younger orthopaedic surgeons had better knowledge about evidence-based medicine. The development and use of evidence-based resources as well as preappraised summaries such as The Journal's evidence-based medicine abstracts and Cochrane reviews were perceived as the best way to move from opinion-based to evidence-based orthopaedic practice.

Adult↗
PubMed1990

[Craniopantograph--an instrument for determination of orbit shape].

The authors describe the structure of principles of function of a measuring-recording instruments, so called craniopantograph. The instrument of own design serves for examination of the spatial variability of the orbit. The obtained measurements of the internal shape of the orbit can be processed later by microcomputer technique. For construction of craniopantograph the principles of function of two typical instruments--craniometer and pantograph were used.

Cephalometry↗
PubMed1998

Methodology for the clinical assessment of medical instrumentation: evaluating ultrasonometers.

Medical instruments can be used for screening, diagnosis, prognosis, and monitoring natural history or therapeutic intervention. With the developing role of ultrasonometry it is important to assess how these instruments will effectively be used for each of these utilizations. No two types of ultrasonometers are the same: there are differences in anatomical sites, measurement variables and methodology in obtaining those variables. To determine optimal utilization the clinician has to evaluate each instrument. Eight factors have to be considered for each utilization comprising of discrimination, precision, reliability, relevance, acceptance by regulatory authorities, inexpensive, acceptability to the patient, and safety. This paper discusses these factors and presents an overview in relationship to the utilization of instruments using ultrasonometry.

Journal Article↗
PubMedDate not supplied

Development of a quality of life index for patients with cancer.

This study developed an instrument to measure the quality of life (QOL) of patients with cancer that would account for individual values, as well as satisfaction. The sample consisted of patients with breast cancer (n = 111) listed in the tumor registry of a major hospital. Ferrans and Power's Quality of Life Index (QLI) was modified based on an extensive review of the oncology literature, which supported content validity. The findings supported the internal consistency reliability of the entire QLI (alpha = 0.95) and of the four subscales: health and functioning, socioeconomic, psychological/spiritual, and family (alphas = 0.90, 0.84, 0.93, and 0.66, respectively). Support for concurrent validity was provided by a strong correlation (r = 0.80) between the QLI and a measure of satisfaction with life. Support for construct validity was provided by significantly higher mean QOL scores for subjects who had less pain, less depression, and were coping better with stress, using the known group technique. The positive results obtained from this assessment and the fact that many patients can complete the QLI independently are important variables to consider when health professionals are selecting instruments for research and practice.

Adaptation, Psychological↗
PubMed2004

Parameters of an optimal physiological state of the masticatory system: the results of a survey of practitioners using computerized measurement devices.

While bioelectronic instruments have been available for nearly 30 years to assist dentists in day-to-day evaluations of patients' masticatory systems, little guidance has been published to support physiological norms or ideals. An electronic questionnaire was developed and administered to an international group of dentists familiar with the use of bioelectronic instrumentation. Respondents were asked to provide feedback on the norms or ideal parameters of jaw movement, masticatory muscle function with electromyography, and joint sounds through electrosonography that they use in guiding evaluation and treatment of patients with temporomandibular disorders, neuromuscular occlusion, and orthodontics. Surveys were collated to determine areas of consensus. Out of 150 surveys, 55 responses were received from dentists representing nine different countries. Sixty percent of the respondents reported treating more than 150 cases in the past five years using bioelectronic testing. While experience ranged from 2-30 years with different types of devices, average experience was longer with mandibular/jaw tracking (mean 15.3 years) and electromyography (mean 14.1 years) than with electrosonography (mean 7.0 years). Parameters proposed as norms or ideals for electromyographic rest and clench values, and mandibular tracking (velocity, freeway space, and trajectory to closure) were very consistent. Although a smaller number of respondents reported utilization of electrosonography, their criteria for data significance and tissue-type genesis of joint sounds were consistent. While the intra-patient variability may limit the diagnostic use of bioelectronic instruments, the current study demonstrates that through decades of experience, dentists have independently arrived at very consistent definitions of an ideal physiology that can be used to guide treatment.

Biomedical Engineering↗
PubMed2000

Kinetic imaging of chlorophyll fluorescence using modulated light.

Fluorometers that measure the kinetics of chlorophyll fluorescence have become invaluable tools for determining the photosynthetic performance of plants. Many of these instruments use high frequency modulated light to measure the rate, efficiency and regulation of photosynthesis. The technique is non-invasive and is effective under diverse environmental conditions. Recently, imaging fluorometers have been introduced that reveal variability in photosynthesis over the surface of a leaf or between individual plants. Most imaging instruments depend on continuous light or low frequency modulated light for fluorescence excitation, which imposes serious limitations on measurements of the fluorescence parameters, especially the minimum fluorescence (F(0)) and variable fluorescence (F(V)). Here, we describe a new instrument that combines the advantage of high frequency modulated light with two-dimensional imaging of chlorophyll fluorescence. The fluorometer produces dynamic images of chlorophyll fluorescence from leaves or plants, providing accurate mapping of F(0) and F(V), and non-photochemical quenching. A significant feature of the instrument is that it can record fluorescence images of leaves in daylight under field conditions.

Journal Article↗
PubMed1987

Safety parameters for avoiding acute ocular damage from the reflected CO2 (10.6 microns) laser beam.

Reflections from instruments in the surgical field involving the CO2 laser beam present a serious ocular hazard. In addition to the use of plastic or glass protective eyewear, this hazard can be minimized by utilizing anodized instruments and recognizing the specific distances at which various reflections are no longer hazardous depending upon certain variables, including laser output wattage, emergent beam lengths, and surface characteristics of the reflecting instruments.

Acute Disease↗
PubMed2006

Testing factor models of the Psychopathy Checklist: Youth Version and their association with instrumental aggression.

Although there is a documented link between psychopathy and instrumental violence in adult offenders, the association between these constructs has not garnered significant attention in adolescent offenders. In this study, we evaluated the relationship between psychopathy and instrumental aggression in a sample of 122 male adolescents incarcerated in a state facility for serious and chronic offenders. We evaluated the primary (2-, 3-, and 4-factor) models of the Psychopathy Checklist: Youth Version (PCL:YV; Forth, Kosson, & Hare, 2003) and assessed their relationship to a separate 5-item measure of instrumental violence. CFA revealed good model fit for the 3- and 4-factor latent variable models of adolescent psychopathy and a single-factor model reflecting a 5-item measure of instrumental violence. Structural equation modeling results indicate that the 4-factor model accounted for 20% of the variance for instrumental violence. In contrast, the 3-factor model of the PCL:YV accounted for 8%, and the 2-factor model accounted for 5% of the variance associated with instrumental violence.

Adolescent↗
PubMed1991

Ultrasound of the postpartum uterus. Prediction of retained placental tissue.

We reviewed ultrasound images an 53 postpartum patients referred for possible retained products of conception and correlated specific ultrasound patterns with clinical and pathologic follow-up. The most common finding in patients with retained placental tissue was an echogenic mass in the uterine cavity, seen in 9 of 11 patients with pathologically proven retained placental tissue. In the remaining 2 patients with pathologically confirmed retained placenta, a heterogeneous mass was seen in the uterine cavity at some point during the course of serial sonography. Retained placental tissue was unlikely when ultrasound demonstrated a normal uterine stripe (n = 18), endometrial fluid (n = 6), or hyperechoic foci in the uterine cavity without an associated mass (n = 17). The latter finding was often associated with recent uterine instrumentation. The sonographic appearance of retained placental tissue is variable, but detection of an echogenic mass in the uterus strongly supports the diagnosis. A heterogeneous mass is sometimes caused by retained placenta, but can also be secondary to blood clots or infected or necrotic material in the absence of placental tissue. Sonographic evaluation for retained products of conception is best done before uterine instrumentation to avoid confusion with iatrogenically introduced air.

Abortion, Incomplete↗
PubMedDate not supplied

An innovative bipolar instrument for laparoscopic surgery.

OBJECTIVE: Bipolar electrosurgery is an excellent method for obtaining hemostasis at laparoscopy. The present study describes and evaluates a bipolar device that can be more versatile and cost effective in advanced operative procedures than the traditional instrumentation. METHODS: This was a retrospective, case-controlled analysis of bipolar instrumentation with a design classification of II-2. A single surgeon in a private practice setting performed all procedures. Sixteen patients, matched for age and pathology were evaluated by videotape review to determine the comparative efficiency of the BiCOAG bipolar dissector/grasper versus traditional Kleppinger bipolar forceps. Efficiency here is defined as comparative operating times in each group. RESULTS: The number of instrument changes per case was counted because this appeared to be the only variable other than time that differentiated the 2 groups. The BiCOAG bipolar dissector/grasper device group had 4 times fewer instrument changes and significantly decreased operating room times when compared with that of the Kleppinger forceps group. Because cost per unit of operating room time was a constant figure, the decrease in cost that resulted due to the decrease in operating time is considered a cost-effective measure. CONCLUSIONS: The BiCOAG bipolar dissector/grasper is a cost-effective, efficient instrument for use in operative laparoscopic procedures.

Case-Control Studies↗
PubMed2005

Saturn's variable magnetosphere.

Since the Cassini spacecraft reached Saturn's orbit in 2004, its instruments have been sending back a wealth of data on the planet's magnetosphere (the region dominated by the magnetic field of the planet). In this Viewpoint, we discuss some of these results, which are reported in a collection of reports in this issue. The magnetosphere is shown to be highly variable and influenced by the planet's rotation, sources of plasma within the planetary system, and the solar wind. New insights are also gained into the chemical composition of the magnetosphere, with surprising results. These early results from Cassini's first orbit around Saturn bode well for the future as the spacecraft continues to orbit the planet.

Extraterrestrial Environment↗
PubMed1990

Accuracy and reproducibility of the Assess peak flow meter.

The variability of peak flow measurements was studied in 24 patients with airway obstruction, using 12 Assess peak flow meters and a Fleisch pneumotachograph type 4 as a standard. The Assess peak flow meter gave systematic under-readings of 19-34% (low accuracy). The value scale of the Assess peak flow meter should be adjusted. As systematic under-readings do not influence the variability in peak flow measurements, variability was only caused by the random error of the instrument. The random error of the Assess peak flow meter was relatively low: about 4% of the measured peak flow value (high precision). The contribution of the Assess peak flow meter to the total variability of peak flow measurements showed a linear relationship (r = 0.53) with the value of the peak flow rate itself and varied from 9% (at 3 l.s-1) to 86% (at 10.8 l.s-1). Reading errors of the peak flow meter were responsible for about 1% of the total variability. The remaining variability is probably caused by the correctness of the peak flow performance and the motivation of the patient.

Adult↗
PubMedDate not supplied

Economic, clinical, and humanistic outcomes: a planning model for pharmacoeconomic research.

Medical, ethical, and societal concerns about costs, access, and quality of care are causing health care practitioners to consider a more comprehensive model for medical decision making. Consequently, interest in research to assess the outcomes of health care has been increasing. The purpose of this paper is to explicate a theoretical framework for identifying, collecting, and using outcomes data to assess the value of pharmaceutical treatment alternatives. Causal relationships between disease, health outcomes, and decisions about medical care interventions (eg, treatment with pharmaceutical products and services) are proposed to address limitations inherent in the traditional medical decision-making model. The Economic, Clinical, and Humanistic Outcomes (ECHO) model depicts the value of a pharmaceutical product or service as a combination of traditional clinical-based outcomes with more contemporary measures of economic efficiency and quality. This integrated approach provides a theoretical basis for considering potential trade-offs among economic, clinical, and humanistic variables in optimizing the allocation of health care resources. The ECHO model is a preliminary step to modeling outcomes from pharmaceutical treatments and services. Data collection instruments need to be developed, and the proposed relationships among outcomes variables should be established empirically. The ECHO model should assist health services researchers in planning, conducting, and evaluating pharmaceutical products and services from a multidimensional perspective.

Causality↗
PubMed2001

Gait variability in community-dwelling older adults.

OBJECTIVES: To describe gait variability at usual and fast walking speeds in community-dwelling older adults and to describe the effects of increasing gait speed on gait variability. DESIGN: Cross-sectional, descriptive study. SETTING: The Cardiovascular Health Study at the University of Pittsburgh. PARTICIPANTS: Ninety-five community-living older adults, 54 women and 41 men, age 65 and older (mean age +/- standard deviation 79.4 +/- 3.37). MEASUREMENTS: Gait measured at participant's usual and fast walking speed collected using an instrumented walkway. Step-length and step-width variability were determined using the coefficient of variation. RESULTS: Step-length variability was greatest in those who walked the slowest (r = -0.66, P < .001); step-width variability was smallest in those who walked the slowest (r -0.37, P < .001). Individuals who could not increase their walking speed (<0.10 m/second) on command had an increase in step-length variability and a decrease in step-width variability, whereas those who could increase their speed (>0.10 m/second) had an increase in step-width variability when walking at a faster speed. CONCLUSIONS: Step-length and step-width variability have opposite associations with gait speed in older adults. Improvement in step-length and step-width variability with attempted acceleration might be a key factor to examine in future studies of disability risk and therapeutic interventions.

Aged↗
PubMed2001

Mechanical root canal preparation with NiTi rotary instruments: rationale, performance and safety. Status report for the American Journal of Dentistry.

The growing use of NiTi rotary instruments in dental practice demands a good understanding of their concept of alloy and design in relation to improved properties and inherent limitations. Nickel titanium's super elasticity allows more centered canal preparations with less transportation and a decreased incidence of canal aberrations. Furthermore, the production of files with increased taper became possible. This is of special importance because of concerns on the achievement of adequate irrigation and close adaptation of the filling material during endodontic treatment. Unique shaft and tip designs should permit the use of a rotary handpiece allowing different tactile awareness. On the other hand, special attention is paid to maximize cutting efficiency and cutting control throughout instrumentation. NiTi rotary instruments are generally used in a crown-down approach and a continuous reaming motion. Consequently, rounder root canal preparations, with less straightening and a smaller amount of apical extrusion is achievable. In spite of their increased flexibility, separation is still a concern with NiTi files. The phenomenon of repeated cyclic metal fatigue and the variable of torsional loading are two important factors in instrument fracture. However, with awareness of the appropriate manipulation and special attention to the equipment used, NiTi systems are safe with a minimal incidence of instrument failure.

Dental Alloys↗