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At least 1,135 records · Page 63Linked to original sources
PubMed2001

Standardization of prostate brachytherapy treatment plans.

PURPOSE: Whereas custom-designed plans are the norm for prostate brachytherapy, the relationship between linear prostate dimensions and volume calls into question the routine need for customized treatment planning. With the goal of streamlining the treatment-planning process, we have compared the treatment margins (TMs) achieved with one standard plan applied to patients with a wide range of prostate volumes. METHODS AND MATERIALS: Preimplant transrectal ultrasound (TRUS) images of 50 unselected University of Washington patients with T1-T2 cancer and a prostate volume between 20 cc and 50 cc were studied. Patients were arbitrarily grouped into categories of 20-30 cc, 30-40 cc, and 40-50 cc. A standard 19-needle plan was devised for patients in the 30- to 40-cc range, using an arbitrary minimum margin of 5 mm around the gross tumor volume (GTV), making use of inverse planning technology to achieve 100% coverage of the target volume with accentuation of dose at the periphery and sparing of the central region. The idealized plan was applied to each patient's TRUS study. The distances (TMs) between the prostatic edge (GTV) and treated volume (TV) were determined perpendicular to the prostatic margin. RESULTS: Averaged over the entire patient group, the ratio of thickness to width was 1.4, whereas the ratio of length to width was 1.3. These values were fairly constant over the range of volumes, emphasizing that the prostate retains its general shape as volume increases. The idealized standard plan was overlaid on the ultrasound images of the 17 patients in the 30- to 40-cc group and the V100, the percentage of target volume receiving 100% or more of the prescription dose, was 98% or greater for 15 of the 17 patients. The lateral and posterior TMs fell within a narrow range, most being within 2 mm of the idealized 5-mm TM. To estimate whether a 10-cc volume-interval stratification was reasonable, the standard plan generated from the 30- to 40-cc prostate model was applied to 5 patients each from the 20- to 30-cc group and the 40- to 50-cc group. Using the standard plan designed for the 30- to 40-cc group, the TMs were closer to 10 mm than to 5 mm for the smaller volume glands and too small for the larger volume ones, assuming an ideal margin of 5 mm. CONCLUSION: The application of standardized plans to prostate brachytherapy is feasible. Stratifying the volume in 10-cc intervals appears to be adequate, suggesting that the majority of cases appropriate for treatment with brachytherapy might be treated with three standard plans. While the authors believe that the use of a limited number of standard treatment plans is feasible, practical, and medically acceptable, it should be emphasized that the use of a standard plan should always be previewed by computer-aided application to the particular patient's planning images.

Brachytherapy↗
PubMedDate not supplied

Cricothyrotomy technique: standard versus the Rapid Four-Step Technique.

Standard cricothyrotomy technique uses a tracheal hook cephalad to the opening to stabilize the trachea during endotracheal (ET) tube passage. A newly described Rapid Four-Step Technique (RFST) uses the tracheal hook caudal to the opening to stabilize the trachea during ET tube passage. This experimental crossover trial compared standard cephalad tracheal hook traction to caudad traction as recommended by RFST in a cadaver model of cricothyrotomy. Outcome measures included the incidence of complications and the size of ET tube able to be passed with each technique. The anterior necks of 30 formalin-fixed cadavers were dissected to completely reveal the cricothyroid membranes and surrounding structures. Two emergency medicine residents performed all cricothyrotomies. Each cadaver was randomly assigned to undergo either standard open technique followed by RFST, or RFST followed by standard open technique. Standard open technique was performed using a #11 scalpel blade, a Trousseau dilator for widening the opening, and a tracheal hook held cephalad through the thyroid cartilage. RFST was performed using a #11 scalpel blade and a tracheal hook held caudad through the cricoid cartilage. Cuffed ET tubes without stylettes were passed in progressively larger sizes until significant resistance was met as determined independently by two physicians. The size of the largest ET tube passed for each technique was recorded. After each attempt the trachea was inspected for evidence of structural damage and the balloon cuff was checked to assess for cuff rupture. There were no complications with standard technique; five cadavers (16.7%) had complications with RFST including one (3.3 %) with balloon cuff rupture and four (13.3 %) with cricoid cartilage fractures. Tracheal damage prevented standard technique performance on three of the cadavers. There was no significant difference between maximal ET tube sizes for standard technique (median size 7.0, mean 6.95 mm internal diameter) versus RFST (median size 7.0, mean 6.82 mm internal diameter). We conclude that RFST may be associated with a higher incidence of complications than standard technique as demonstrated by our cadaver model of cricothyrotomy. We were unable to demonstrate a difference between the two techniques with regards to size of ET tube able to be passed.

Aged↗
PubMed2002

Adherence of published diabetes mellitus practice guidelines to methodologic standards of guideline development.

There are multiple practice guidelines published pertaining to diabetes care. Experts have formulated methodologic standards of guideline formulation. To determine whether practice guidelines pertaining to diabetes and published in peer-reviewed publications and the Internet adhered to established methodologic standards of guideline development. We identified all guidelines pertaining to diabetes care published between 1980 and 2000 using a computerized search of Medline, the Practice Guidelines Clearinghouse, the Institute for Clinical Systems Improvement Web site, and a global internet search engine. We used a previously validated 25-item assessment tool to determine guideline adherence to methodologic standards in three categories: guideline development and format, identification and summary of evidence, and formulation of recommendations. We conducted a multivariable regression analysis to determine the influence of guideline author, publishing medium, year of publication, and guidelines length on adherence to methodologic standards of guideline development. We evaluated 43 guidelines: 33% published on the Internet, 66% in peer-reviewed journals; 51% published by organizations, and 49% by individual experts. Of a maximum of 25 methodologic standards, the number of standards adhered by a guideline was 9 (range, 2 to 19). Mean proportion (SD) of guidelines that adhered to methodologic standards on guideline development and format was 48% (28); on identification and summary of evidence, 21% (22); and on the formulation of recommendations, 36% (27). Longer guidelines had greater adherence to methodologic standards (P < 0.0001). Guidelines pertaining to diabetes care published on the internet and in peer-reviewed publications do not meet most methodologic standards of guideline development.

Diabetes Mellitus↗
PubMed1997

Obstetric anaesthesia: an approach to improving the standards of services.

There has been considerable discussion about obstetric anaesthesia standards and about the role of peer review in quality improvement. We carried out two postal surveys in 1990 and 1991 in major obstetric departments in Northern England, in order to assess practice and facilities against professionally derived standards, with the aim of stimulating and reviewing change. The reference standards were a local adaptation of those produced by the Obstetric Anaesthetists Association, and covered operating facilities, anaesthetic equipment, management and manpower, training, and protocols. In 1990, considerable variation in practice and facilities was identified with deficiencies in all hospitals. After feedback of the results of the first survey, a further survey conducted in 1991 identified improvement in 23/26 standards. Reference to standards was widely included in business plans and contracts for services. Following further feedback of the second survey and some revision of standards, a third survey was carried out using site visits. This revealed further improvement in 8/26 standards, but apparent deterioration in 11/26. The overall change from the first to the third survey was of apparent improvement in 15/26 standards and deterioration in 6/26. Surveys of practice against professionally derived standards and the targeted feed back of results can lead to improvements in practice and facilities.

Journal Article↗
PubMed2000

Using standardized patients to measure quality: evidence from the literature and a prospective study.

BACKGROUND: Use of standardized patients for evaluating the clinical skills of medical students and medical trainees is commonplace. This has encouraged the use of standardized patients to evaluate the quality of physician practice in outpatient settings. However, there may be substantive differences between observing student performance and evaluating whether the provision of care meets defined quality criteria. OBJECTIVES: This study had two primary objectives: (1) to review studies that use standardized patients to evaluate physician performance and (2) to ascertain directly whether standardized patients could be useful in assessing quality of outpatient care. METHODS: A comprehensive literature review of studies that used standardized patients to assess physician performance was conducted. A prospective study that included 20 physicians at two outpatient settings and 27 actor patients assessed quality of care using eight clinical cases divided into five clinical domains, each of which had explicit criteria checklists based on widely accepted guidelines. RESULTS: The literature review identified five important issues: developing scenarios, selecting explicit criteria, standardizing standardized patient training, creating subterfuges, and ensuring reliability and validity of measures. In the study, trained standardized patients were able to assess physician practice accurately for common medical conditions, using proven criteria linked to health outcomes. The detection rate was 3%. There was no performance variation between actors for seven of the eight cases. CONCLUSIONS: Using standardized patients to measure the quality of care is practical and feasible. The major methodological challenge is incorporating observable evidence-based criteria into realistic scripts and objective checklists. The major logistical challenge is obtaining and maintaining undetected entry into physicians' offices.

Clinical Competence↗
PubMed1998

How to create awareness and ensure broad dissemination of health informatics standards.

There is a range of organisations with responsibility for information standards development within Australia. These include Standards Australia, which is formally linked to the International Organisation for Standards (ISO), the National Health Information Management Group, which deals with the government sector and several statutory organisations such as the Australian Institute of Health and Welfare and the National Centre for Classification in Health. The different constituencies involved with each of these organisations, the scope of healthcare informatics and the rate of organisational and technological change in the industry present a significant challenge in ensuring that the standard setting process is highly visible, responsive and capable of demonstrating its value through effective implementation. Creating awareness and ensuring broad dissemination of healthcare informatics standards is a key component in meeting this challenge. This can operate at a number of levels from strategic to operational. At the strategic level, it requires active engagement and commitment of the key decision-makers, both political and professional. This may require directly lobbying and promoting the benefits of standardisation to those decision-makers but can be achieved even more effectively by creating industry awareness and demand through carefully targeted presentations on the impact of standards to broader health industry forums. At the tactical level, the standards development medium itself can be used to engage and gain commitment from government, professionals, vendors and the health industry by operating as an inclusive, open and effective process. At the operational level, there is the opportunity for much more efficient use of technology to create awareness of both these processes and their outcomes. The establishment in Australia of a web enabled National Health Information Knowledge base built around ISO standards is one example of the type of development which will assist in the acceleration of awareness of standards and standardisation, which is needed to cope with the increasing demand.

Australia↗
PubMed1992

Standard thermodynamic formation properties for the adenosine 5'-triphosphate series.

The criterion for chemical equilibrium at specified temperature, pressure, pH, concentration of free magnesium ion, and ionic strength is the transformed Gibbs energy, which can be calculated from the Gibbs energy. The apparent equilibrium constant (written in terms of the total concentrations of reactants like adenosine 5'-triphosphate, rather than in terms of species) yields the standard transformed Gibbs energy of reaction, and the effect of temperature on the apparent equilibrium constant at specified pressure, pH, concentration of free magnesium ion, and ionic strength yields the standard transformed enthalpy of reaction. From the apparent equilibrium constants and standard transformed enthalpies of reaction that have been measured in the adenosine 5'-triphosphate series and the dissociation constants of the weak acids and magnesium complexes involved, it is possible to calculate standard Gibbs energies of formation and standard enthalpies of formation of the species involved at zero ionic strength. This requires the convention that the standard Gibbs energy of formation and standard enthalpy of formation for adenosine in dilute aqueous solutions be set equal to zero. On the basis of this convention, standard transformed Gibbs energies of formation and standard transformed enthalpies of formation of adenosine 5'-trisphosphate, adenosine 5'-diphosphate, adenosine 5'-monophosphate, and adenosine at 298.15 K, 1 bar, pH = 7, a concentration of free magnesium ions of 10(-3) M, and an ionic strength of 0.25 M have been calculated.

Adenine Nucleotides↗
PubMed1998

Relative or Absolute Standards in Assessing Medical Knowledge Using Progress Tests.

Norm-referenced pass/fail decisions are quite common in achievement testing in health sciences education. The use of relative standards has the advantage of correcting for variations in test-difficulty. However, relative standards also show some serious drawbacks, and the use of an absolute and fixed standard is regularly preferred. The current study investigates the consequences of the use of an absolute instead of a relative standard. The performance of the developed standard setting procedure was investigated by using actual progress test scores obtained at the Maastricht medical school in an episode of eight years. When the absolute instead of the relative standard was used 6% of the decisions changed: 2.6% of the outcomes changed from fail to pass, and 3.4% from pass to fail. The failure rate, which was approximately constant when using the relative standard, varied from 2% to 47% for different tests when an absolute standard was used. It is concluded that an absolute standard is precarious because of the variations in difficulty of tests.

Journal Article↗
PubMed2004

Standard and low-dose IGF-I generation tests and spontaneous growth hormone secretion in children with idiopathic short stature.

OBJECTIVE: Abnormalities in the GH-IGF-I axis, consistent with GH insensitivity (GHI), have been reported in some patients with idiopathic short stature (ISS). The standard IGF-I generation test (IGFGT) has not demonstrated mild GHI in subjects with ISS. The aim of this study was to investigate the GH-IGF-I axis in ISS by performing standard and novel low-dose IGFGTs together with determination of spontaneous GH secretion. PATIENTS AND METHODS: Twenty-one (17 male) prepubertal children with ISS, mean age 8.3 years (4.5-12.2), mean height -3.48 SD (-5.40 to -1.79), mean peak GH to provocation with glucagon/clonidine 32.3 mU/l (14.1-66.0) were studied. Serum IGF-I and IGFBP-3 levels were measured during standard (GH 0.033 mg/kg/day x 4) and low (GH 0.011 mg/kg/day x 4) dose IGFGTs at 0, 12, 36 and 84 h. The low-dose IGFGT was performed in seven naive GH-deficient patients (4 male), mean age 8.5 years (range 4.1-11.1). Determination of spontaneous 24-h GH secretion was performed in the 21 ISS patients. RESULTS: Basal IGF-I and IGFBP-3 standard deviation scores (SDS) in ISS patients were -1.39 (-2.4-1.16) and -0.45 (-1.13-0.38), respectively, IGF-I being lower than IGFBP-3 (P < 0.0001). IGF-I increased in the standard IGFGT at 12 h (P < 0.005), 36 h (P < 0.001) and 84 h (P < 0.001); maximal increment 1.54 (-0.32-3.48), and in the low-dose test at 12 h (P < 0.005), 36 h (P < 0.001) and 84 h (P < 0.005); maximal increment 0.53 (0.08 to -1.23). IGFBP-3 SDS increased in the standard IGFGT at 36 h (P < 0.01) and 84 h (P < 0.001); maximal increment 0.72 (-0.44-1.96), and in the low-dose test at 84 h (P < 0.005); maximal increment 0.33 (-0.08-0.87). Five/19 patients with an IGF-I response > 2 x coefficient of variation (CV) of assay in the standard test failed to respond in the low-dose test, suggestive of mild GHI. In GH-deficient patients, IGF-I increased at each time point (P < 0.05) and IGFBP-3 at 36 h (P < 0.05). Mean GH secretion, expressed in SDS, compared with 66 normal stature controls was: basal GH -0.48 (-0.84-0.93), height of GH peaks compared with zero -0.36 (-1.26-1.51) (both P < 0.05), total GH secretion -0.76 (-1.22-0.42), total GH secretion above baseline -0.67 (-1.21-0.94) (both P < 0.01). CONCLUSIONS: In children with ISS, basal IGF-I and IGFBP-3 SDS values were below the mean, IGF-I showing a greater response in both IGFGTs. In the standard IGFGT, the IGF-I increase at 36 h was equal to that at 84 h. The low-dose IGFGT, in combination with the standard test, may identify patients with mild GHI.

Case-Control Studies↗
PubMed2000

The development of competency standards for specialist critical care nurses.

In defining the contemporary role of the specialist nurse it is necessary to challenge the concept of nursing as merely a combination of skills and knowledge. Nursing must be demonstrated and defined in the context of client care and include the broader notions of professional development and competence. This qualitative study sought to identify the competency standards for nurse specialists in critical care and to articulate the differences between entry-to-practice standards and the advanced practice of specialist nurses. Over 800 hours of specialist critical care nursing practice were observed and grouped into 'domains' or major themes of specialist practice using a constant comparison qualitative technique. These domains were further refined to describe attributes of the registered nurses which resulted in effective and/or superior performance (competency standards) and to provide examples of performance (performance criteria) which met the defined standard. Constant comparison of the emerging domains, competency standards and performance criteria to observations of specialist critical care practice, ensured the results provided a true reflection of the specialist nursing role. Data analysis resulted in 20 competency standards grouped into six domains: professional practice, reflective practice, enabling, clinical problem solving, teamwork, and leadership. Each of these domains is comprised of between two and seven competency standards. Each standard is further divided into component parts or 'elements' and the elements are illustrated with performance criteria. The competency standards are currently being used in several Australian critical care educational programmes and are the foundation for an emerging critical care credentialling process. They have been viewed with interest by a variety of non-critical care specialty groups and may form a common precursor from which further specialist nursing practice assessment will evolve.

Australia↗
PubMed2002

Visual field assessment and the Austroads driving standard.

PURPOSE: To compare the conventional (Humphrey 24-2) automated visual field testing with the Goldmann standard visual field test for driving, and to predict how many patients with glaucoma may not meet the Australian driving standard with respect to visual fields. METHODS: Four patients (retinitis pigmentosa, glaucoma or vigabatrin treatment) with marked visual field defects as determined by uniocular static computerized perimetry (conventional testing) were re-evaluated with binocular kinetic Goldmann IV4e target field test (Australian driving standard). A series of 48 consecutive patients seen by the Glaucoma Inheritance Study in Tasmania were assessed with both static computerized perimetry and the Goldmann IV4e target test. RESULTS: The four patients with severe visual field defects (on computerized perimetry) were found to meet the driving standard on the binocular Goldmann IV4e target test. On computerized perimetry, 15 of 48 patients from the Glaucoma Inheritance Study in Tasmania were found to have visual field defects of sufficient severity that they may not meet the driving standard. However, only five of these patients failed the driving standard for visual fields, two of whom were still driving. CONCLUSIONS: Patients with severe field defects on conventional uniocular automated perimetry may still meet the Goldmann standard visual field test for driving. Approximately 30% of glaucoma patients would have visual field loss shown on Humphrey 24-2 test of a severity that requires further testing to determine if they meet the driving standard. Ten per cent of glaucoma patients tested did not meet the driving standard for visual fields.

Adult↗
PubMed2002

Severe underreporting of energy intake in normal weight subjects: use of an appropriate standard and relation to restrained eating.

OBJECTIVE: To assess the influence of different standards and restrained eating on underreporting in healthy, non-obese, weight-stable young subjects. DESIGN AND SUBJECTS: Eighty-three young adults (20-38 years, 55 women, 28 men) were assessed under weight-stable conditions with a 7-day dietary record and the three-factor eating questionnaire by Stunkard and Messick. Resting energy expenditure (REE; indirect calorimetry) plus data derived from physical activity records (PA) (Standard 1) or REE times an activity factor (AF) (Standard 2) was used as standard for total energy expenditure (TEE). For comparison, doubly labelled water (DLW) was used to measure TEE in a subgroup of subjects. RESULTS: There was an association between self-reported energy intake and Standard 2 but not with Standard 1. When compared with DLW both calculated standards were inaccurate, but Standard 2 avoided high levels of overreporting. Using Standard 2 to identify 'severe' underreporting (SU; as defined by a deviation of energy intake (EI) and TEE of >20%), SU was seen in 37% of all subjects. It was more frequently found in women than in men (49% of women, 14.3% of men, ). Underreporting subjects had a reduced EI but there were no significant differences in nutritional status (body weight and height, body mass index, fat mass and fat-free mass), energy expenditure and the proportion of energy from macronutrients between normal and underreporting subjects. However, high restraint was associated with a higher degree of underreporting in the total group, whereas disinhibition had an influence only in men. CONCLUSIONS: A high prevalence of SU is seen in non-obese subjects. Characteristics of eating behaviour (restraint and disinhibition) were associated with underreporting but seemed to have a different influence in men and women.

Adult↗
PubMedDate not supplied

A method for assessing age-standardized weight-for-height in children seen cross-sectionally.

Weight-for-height standards in children are usually constructed on the basis that the expected weight for a given height does not depend on age, an assumption which is unjustified. The present paper investigates regression standards of age-standardized weight for age-standardized height, the standardization being achieved by expressing weight and height as fractions of the 50th centile for age from a suitable growth standard. The precise choice of standard is not critical. Data on 4631 children from five different countries, exhibiting a wide spectrum of growth status, show that throughout childhood until puberty, the following ratio is appropriate as a simple and convenient index of weight-for-height: age-standardized weight/(age-standardized height)2. During puberty a larger power than 2 is required, so the index as specified is inappropriate. Approximate values for the distribution centiles of the index are suggested. The index may be used to assess degree of malnutrition or obesity, for individuals or groups seen on a single occasion. A slide-rule is described which calculates the index directly, given the child's sex, age, height and weight.

Adolescent↗
PubMed1988

On the relationship between radiation standards for the general public and limitation of lifetime risk.

This paper discusses the relationship between standards for limiting radiation exposures of individuals in the general public and limitation of lifetime risk. Most current radiation standards for the public in the United States specify limits on dose for each year of exposure. Particularly for internal exposures, we show that such standards may correspond poorly with a limit on lifetime risk when the age dependence of radionuclide intakes and dose is taken into account. We then show that standards which specify limits on annual dose averaged over a lifetime, with a subsidiary limit on dose in any year, correspond more closely with a limit on lifetime risk. Finally, we discuss standards for public exposures that are expressed directly as limits on lifetime risk. The development of risk standards would require consideration of age-dependent radiogenic risks and competing risks from all other causes as well as age-dependent dosimetry. We present sample calculations of lifetime risks from acute and chronic intakes that would support such a standard. We suggest that implementation of a standard for lifetime risk would require modification or abandonment of several radiation protection practices embodied in standards which specify limits on dose.

Adolescent↗
PubMed2005

Has a 3-fold decreased dose of bacillus Calmette-Guerin the same efficacy against recurrences and progression of T1G3 and Tis bladder tumors than the standard dose? Results of a prospective randomized trial.

PURPOSE: We determined if a third of the dose of intravesical bacillus Calmette-Guerin (BCG) has the same efficacy than a standard dose for decreasing the risk of recurrence and progression after transurethral resection in patients with superficial high risk (stages T1G3 and carcinoma in situ) bladder cancer. Also, we evaluated toxic side effects. MATERIAL AND METHODS: A total of 155 patients with a mean age +/- SD of 67 +/- 10.1 years with superficial bladder cancer, including stages T1G3 in 90, a Tis primary tumor in 23 and associated Tis disease in 42, were enrolled and randomly assigned to be treated after transurethral resection of all visible lesions with intravesical BCG, Connaught strain (weekly x 6 and fortnightly x 6 thereafter) with the standard dose of 81 mg or with the decreased dose of 27 mg. RESULTS: Median followup was 61 months (range 3 to 102). Disease recurred in 32 patients (39%) treated with the standard dose and in 33 (45%) treated with the decreased dose. Median time to recurrence was not attained in the standard dose arm and it was 63 months in the decreased dose arm. Kaplan-Meier estimates for time to recurrence did not reveal differences between the 2 doses (p = 0.405). Tumor progressed in 20 patients (24.7%) with the standard dose and in 19 (26%) with the decreased dose. Four patients (6.1%) with Tis had local extension into the prostatic urethra and ducts, including 3 (8.3%) treated with the standard dose and 1 (3.4%) treated with the decreased dose. Median time to progression was not attained in either arm. Kaplan-Meier estimates for time to progression did not differ significantly (p = 0.7997). Deferred cystectomy for progression was performed in 7 patients (8.4%) treated with the standard dose and in 7 (9.5%) of those treated with the decreased dose. Subgroup analysis by patient age, tumor status, number, size and T stage (T1G3 vs Tis) did not differ significantly. The groups did not differ in disease specific mortality, which was 12.2% in the standard dose arm and 16.4% in the decreased dose arm. Mean disease specific survival +/- SE was 86.96 +/- 4.14 and 83.73 +/- 4.73 months, respectively. CONCLUSIONS: Our results suggest that a 3-fold decreased dose of intravesical BCG is as effective as the standard dose against progression in patients with high risk stages T1G3 and Tis superficial bladder carcinoma but with significantly less toxicity.

Adjuvants, Immunologic↗
PubMed1976

Defective-interfering particles of Semliki Forest Virus: structural differences between standard virus and defective-interfering particles.

Serial passaging of Semlike Forest virus in BHK cells at a constant input multiplicity of 50 p.f.u./cell resulted in a 4 log10 drop in yield of infectious virus by passage 9. An interference analysis showed that this drop was due to the presence of defective-interfering (DI) particles. Attempts were made to separate the DI particles from standard virus by equilibrium and velocity centrifugation. Only equilbrium centrifugation on CsCl resolved the DI particles (identified by interference analyses) from standard virus. The buoyant density of the DI particles (1.23 g/ml) was higher than that of standard virus (p = 1-20 g/ml). No difference was observed between the structural porteins of standard virus and DI particles. Analysis of the RNA of standard virus and DI particles showed that whereas standard virus contained only 42S RNA (mol. wt. approx. 4-2 X 10(6), DI particles contained two small pieces of RNA of mol. wt. 0.81 and 0-75 X 10(6) respectively. Infectivity assays showed that these low mol. wt. species were not only non-infectious but also interfered with the infectivity of 42S RNA from standard virus. Nucleocapsids derived from purified DI particles had a buoyant density 0-02 g/ml greater than the nucleocapsids from standard virus. Analysis of the RNA from DI nucleocapsids showed it to be entirely of the low mol. wt. class. To account therefore for the density difference not only between DI particles and standard virus but also between their respective nucleocapsids we propose that each SFV DI particle contains several molecules of the low mol. wt. RNA species.

Cell Line↗
PubMed1997

Does medical audit lead to explicit standards? Experience with thrombolysis in four UK hospitals.

The setting of explicit standards against specific criteria is a recognized part of the medical audit cycle, but often in practice it has been neglected, implicit judgements being used instead. The conduct of a study to evaluate audit among physicians in four UK district general hospitals provided an opportunity to encourage the setting of explicit standards and observe the results. The subject chosen for audit by the participating physicians was the extent of use of intravenous thrombolysis in patients with suspected acute myocardial infarction (AMI). Standard setting was requested at initial peer review meetings held to review baseline results. This was followed up by a written request to lead consultants and subsequent telephone calls. Two out of the four participating hospitals set technical standards, which excluded patients with contra-indications from the denominator. The other two hospitals set population standards as requested, one with considerable reluctance and scepticism. Each hospital set separate standards for definite AMIs and for probable AMIs. Six out of the eight standards set were achieved in at least one of four audits conducted in each hospital. Time trends were difficult to interpret because of small numbers. The amount of discussion between the lead consultant and colleagues about standards was highly variable, but there was no clear relationship between the process for agreeing standards in a particular hospital and subsequent attainment.

Chest Pain↗
PubMed2003

Practice standards for optometry and optometric practice accreditation.

BACKGROUND: To assist optometrists to deliver care more efficiently and effectively, in 1995 Optometrists Association Australia decided to develop standards that would assist optometrists in better managing their practices. Existing practice management standards for health professionals were thought to be either not specific enough for optometric practice or to have shortcomings in the context of optometric practice in Australia. METHODS: Following a literature search, material previously developed by Optometrists Association Australia to assist practitioners with management of their practices and standards from other professions were used to assist with the development of a draft set of standards for optometric practices in Australia. Successive drafts were circulated for comment to optometrists in practice, non-optometrists with experience in the development of practice standards for other health professions and to Australian General Practice Accreditation Limited. The comments were used to refine the standards and the accreditation guidelines to their final form. RESULTS: Optometric Practice Standards suitable for use in a practice accreditation program were developed. The standards comprise seven sections--Practice administration, Quality assurance, Rights and needs of the patient, Practice services, Practice facilities, Communication and Patient records. These sections are divided into criteria that provide the detail of the requirements of the standard. Indicators describing how criteria can be assessed accompany the criteria.

Accreditation↗