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PubMed2002

An evaluation of the inter-observer and intra-observer variability of the ultrasound diagnosis of polycystic ovaries.

BACKGROUND: This prospective observational study was undertaken to evaluate the reliability and consistency of ultrasound diagnosis of polycystic ovarian syndrome (PCOS). METHODS: Eighteen women with clinical and biochemical features suggestive of PCOS and nine normal control women underwent transvaginal ultrasound scan by a single ultrasonographer. The 27 ovarian scans were video-recorded and the recordings were later edited and arranged randomly so that each record appeared twice at random on the tape producing a total of 54 ovarian scans. Four experienced observers independently reviewed the recordings. The observers scored each case as follows: normal, possible polycystic ovary (PCO) and definite PCO. RESULTS: The mean intra-observer agreement was 69.4% (kappa = 0.54) and the mean inter-observer agreement was 51% (kappa = 0.28). CONCLUSION: The results suggest that the currently used ultrasonographic criteria for the diagnosis of polycystic ovaries do have significant intra-observer and inter-observer variability and as such must be considered subjective. Transvaginal ultrasonography alone may not therefore be a reliable method of diagnosing or excluding PCOS.

Adult↗
PubMed1994

The 'Ermenonville' classification of observations at coronary angioscopy--evaluation of intra- and inter-observer agreement. European Working Group on Coronary Angioscopy.

A European coronary angioscopy working group has been established to create and evaluate a classification system for angioscopic observation. The 'Ermenonville' classification features items, graded in 3-5 categories, such as lumen diameter, shape of narrowing, colours of surface, atheroma, dissection, thrombus, etc. Inter- and intra-observer agreement on the interpretation of angioscopic images, using this classification system, was studied within the working group. Kappa values for chance-corrected intra-observer agreement of the diagnostic items were 0.51-0.67. The mean kappa values for inter-observer agreement were very low at 0.13-0.29. The important items, such as red thrombus and dissection were studied after recoding as either present or absent. These items proved to have a good intra-observer agreement, and an acceptable inter-observer agreement after recoding. Other angioscopic diagnoses should be made with caution. Multicentre angioscopy studies should make use of an angioscopy core laboratory. A set of definitions for coronary angioscopy is proposed, and this working group will re-evaluate observer agreements using these definitions.

Angioscopy↗
PubMed2003

Inter-observer and intra-observer variability in hepatology.

OBJECTIVES: A determination of the inter-observer variability is an important step before determining diagnostic accuracy and requires a specific methodology and statistical tests. The aim of this study was to report the results, characteristics and methodological quality of agreement studies performed in hepatology. METHODS: A search of published studies yielded 42 that could be used in this evaluation: three were clinical studies, 11 were in the field of endoscopy, 12 in histopathology and 16 in radiology. The studies were described with a grid of 28 items and evaluated with a quality score (QUAS; maximum, 35) including 22 items. RESULTS: The following agreement level was noted: intra-observer > inter-observer > inter-centre. The following signs had good agreement. Endoscopy: size and red signs of oesophageal varices; histopathology: cirrhosis, fibrosis and steatosis; Doppler: mean portal vein and superior mesenteric artery velocities, hepatic artery area and perfusion indexes. Frequent methodological weaknesses were noted. The real agreement (such as the kappa index excluding chance), and the prevalence of signs and biases were rarely assessed. Standardized observations (67% of the studies), blind assessment (48%), simultaneous observations (7%), and the recording technique were not frequently used. The mean QUAS was 13 +/- 6 with 17 +/- 4 in histopathology versus 11 +/- 6 in radiology (P < 0.05). Using multiple regression, four variables independently predicted the QUAS with R2 = 0.77: adapted tests, multiple observations, intra-class correlation coefficient and agreement proportion. CONCLUSIONS: Methodology was often insufficient. Agreement is often measured under biased conditions. Some areas were not or were rarely studied, e.g., biology and ultrasound. The agreement and QUAS were often poor, suggesting the need for studies with improved observation and methodological quality of agreement.

Esophageal and Gastric Varices↗
PubMed1989

[The effects of the viewpoints and observers' traits on the observational learning of altruistic behavior].

This study was to examine the changes of altruistic responses through observational learning (OL) in elementary school children (4th graders) with the conditions of the different viewpoints and observers' traits. The OL was the symbolic modeling of altruistic behavior by presentation of pictures with narration. All the stories had the same situation, but differed whether the actor behaved himself in an altruistic fashion to the object, or not. Observers' viewpoints were determined by the instruction: they were told to observe the story as if they were one of the characters and to pay attention to emotional responses or behavior of the character. The emphasis of each story corresponded to the viewpoint. Out of these eight combined experimental conditions six were performed. Traits were concerned with observers' impression, empathy, and evaluation of the story. The response measure was the change of rating between pre- and post-questionnaires through observation. The effect of OL was higher significantly when the viewpoint directed to the characters' emotion. Observers who reacted strongly to empathy and impression items showed higher altruistic changes.

Altruism↗
PubMed1993

[Cutaneous or subcutaneous calcinosis observed in leprosy patients. 1. Clinical observations].

A roentgenographic examination was made for the limbs of leprosy patients with calcinosis in whom atrophic cutaneous sclerosis and subcutaneous induration or infiltration were observed. The observation results are summarized as follows. 1. Atrophic cutaneous sclerosis was one of a sequela in lepromatous lesion, especially in case of ENL, and it was observed to occur frequently at the extended sides of 1/3distal part from the forearm and the crus mainly. The atrophied cutaneous surface was tinged with lustrous red. It was able to observe calcium deposition directly just under the skin and/or in the shallow subcutaneous region from the roentgenogram of the site. The roentgenographic patterns were demonstrated as if many granules were scattered, and also the dendric and reticular platy-expansions were detected in some cases. The enucleated parts seemed to be similar to the cancellous bone. It might be said that dystrophic calcinosis cutis developed by inducing histological disorder is one of the origin of such a calcinosis, because the skin in these regions is deficient in the mobility and tends to provoke the circulatory disorder in case of chronic inflammation as discerned in lepromatous lesion. 2. An induration in subcutaneous tissue is lipid lump being as it was when chaulmoogra oil was injected and not undergo absorption of the oil. The lipid lumps enveloped in the tunic were observed in the site of lateral upperarm and the front of femur. They seemed to be remained almost all as it was. It was observed that the lipid lumps, as such, were adjacent to the outer layer of fascia, but not in the muscle. And there are some cases where the oil flowed from the injection site through the hypodermis and got the lipid lumps formed in the forearm and/or the crus. Roentgenogram of that showed the existence of calcinosis regardless of size which transmissivity of X-ray had an irregular pattern. The enucleated lipid lumps were easily cut to pieces by scalpel. 3. It may be said that the calcinosis observed in atrophic cutaneous sclerosis due to lepromatous lesion or lipid lump of unabsorbed chaulmoogra oil makes it necessary for its healing to be 10-20 years. 4. Roentgenogram at that time revealed no abnormality as to serum calcium, phosphorous and/or alkaline phosphatase values.

Adult↗
PubMed1999

Prediction of human observer performance by numerical observers: an experimental study.

Numerical observers are investigated for predicting the outcome of a free-response human observer study involving the detection of simulated pulmonary nodules in images reconstructed from low-dose computed tomography projection data by use of several reconstruction algorithms. A new way of calculating the figure of merit of a numerical observer is proposed wherein the detectability of signals in a particular image depends on the noise properties associated with that image and not the other images in the data set. The resulting variants of numerical observers are found to perform better than their traditional counterparts. In particular, the imagewise variant of the region-of-interest observer is found to predict best the rank ordering of algorithms by human observers for the free-response task.

Algorithms↗
PubMed2000

OBSERVE: a multimedia course on the observational analysis of behavior.

OBSERVE is a preliminary release of a multimedia course for teaching undergraduate and graduate students how and why to study behavior by direct observation. The instructional text and commentary and the self-test and examination materials are built around a series of exercises in which the student observes and categorizes film clips of the behavior of several different species in several different ways. Incorporation of elements from The Observer software for computer recording and video analysis implements fully computerized continuous recording. At present, the text, together with check sheets that the program generates, enables a comparison between one-zero, instantaneous, and continuous sampling of the same behavioral excerpts. Matrices are printed out for an exercise in calculating interobserver reliability. Another section supports carrying out and writing up a small observational project on human behavior in the field. Plans for the future development of OBSERVE are briefly described.

Behavioral Sciences↗
PubMed1997

HOME inventory and NCATS: relation to mother and child behaviors during naturalistic observations. Home Observation for Measurement of the Environment. Nursing Child Assessment Teaching Scale.

The purpose of this study was to determine the relationships among the Nursing Child Assessment Teaching Scale (NCATS), the Home Observation for Measurement of the Environment (HOME) inventory, and interactive behaviors observed in the home for fifty-three 3-year-old, prematurely born children and their mothers. The total HOME score showed high internal consistency, with moderate subscale levels. NCATS total score showed high internal consistency, but low to moderate subscale consistency. Combining NCATS subscales into a mother subscale and child subscale improved internal consistency. The HOME and the NCATS mother subscale correlated with observed maternal behaviors, but the NCATS child subscale was unrelated to child behaviors. Relationships between observed behaviors and HOME scores did not differ for high- and low-education mothers or for Caucasians and African Americans, but only low-education mothers and African Americans exhibited correlations between NCATS scores and observed behaviors. These results show the HOME, NCATS, and naturalistic observations measure related, but not overlapping, aspects of the mother's contribution to her relationship with her child, but the NCATS child subscale should be used with caution with 3-year-olds.

Adult↗
PubMed2003

Modulation of motor cortex excitability in the left hemisphere during action observation: a single- and paired-pulse transcranial magnetic stimulation study of self- and non-self-action observation.

Motor system excitability was tested by transcranial magnetic stimulation (TMS), and F-wave and H-reflex evaluation in different action observation tasks. Our aim was to investigate the effects produced by self- versus non-self-hand movement observation (MO). No significant differences were found between the self- and non-self-conditions. Movement observation significantly modulated motor cortex excitability, producing an increase in the amplitude of motor evoked potentials (MEPs) with a single magnetic pulse and a reduction in intracortical inhibition (ICI) with paired-pulse stimulation. No significant changes were found in motor cortex excitability during the observation of geometric objects. Motor imagery produced similar effects to those of action observation; no significant differences in modulation of motor system excitability between motor imagery and action observation were found in those muscles involved in actual motor execution. No significant effect on spinal excitability was found in any of the test conditions.

Adult↗
PubMed1995

Very-long-baseline radio interferometry (VLBI) observations of gamma-ray blazars: results from millimeter-VLBI observations.

VLBI observations of the extremely gamma-bright blazar PKS 0528+134 at 8, 22, 43, and 86 GHz reveal a strongly bent one-sided-core jet structure with at least three moving and two apparently stationary jet components. At the highest observing frequencies the brightest and most compact jet component (the VLBI core) is unresolved with an upper limit to its size of approximately 50 microarcsec corresponding to approximately 0.2 parsec [H0 = 100 km.s-1.Mpc-1 (megaparsec-1), q0 = 0.5, where H0 is Hubble constant and q0 is the deceleration parameter]. Two 86-GHz VLBI observations performed in 1993.3 and 1994.0 reveal a new jet component emerging with superluminal speed from the core. Linear back-extrapolation of its motion yields strong evidence that the ejection of this component is related to an outburst in the millimeter regime and a preceding intense flare of the gamma-flux density observed in early 1993. This and the radio/optical "light curves" and VLBI data for two other sources (S5 0836+710 and 3C 454.3) suggest that the observed gamma-radiation might be Doppler-boosted and perhaps is closely related to the physical processes acting near the "base" of the highly relativistic jets observed in quasars.

Journal Article↗
PubMed1978

The Behavior Observation Instrument: a method of direct observation for program evaluation.

The background and development of a multicategory direct observation system, the Behavior Observation Instrument (BOI), is described. This time-sampling procedure for recording the behavior of persons is demonstrated in several treatment settings and the results applied to issues of program evaluation. Elements that have prevented direct observation from being widely adopted, such as costs, manpower, and training requirements, are systematically analyzed. A basic psychometric analysis of the instrument is used to determine optimum frequency and duration of observation intervals as well as observer agreement. The results imply that direct observation methods, once assumed by some to belong to the special province of the single-subject design, can be used to assess the effects of programs on groups of psychiatric clients in an efficient and economic manner.

Activities of Daily Living↗
PubMed1994

Observations on structural features and characteristics of biological apatite crystals. 9. Observation on dissolution of carious enamel crystals.

In a series of studies to investigate the basic structural features and characteristics of the biological apatite crystals using a transmission electron microscope, we examined the ultrastructure of the human enamel, dentin, and bone crystals through the cross and longitudinal sections at near atomic resolution. Subsequently, using the same approach, we have been able to directly examine the images of the lattice imperfections in the crystal lattices of the human tooth and bone crystals, and the images of the fusion of the crystals. In this research, furthermore, using transmission and scanning electron microscopes, we examined the dissolution of the enamel crystals caused by the carious enamel from the same viewpoint. The material used for the observation of the dissolution of the enamel crystals was obtained from the region which corresponds to the middle layer of the enamel at the portion near the wall of a carious cavity caused by the fissure caries on the occlusal surface of the lower first molars. Small cubes of the materials used for the observation by transmission electron electron microscope were fixed in glutaraldehyde and osmium tetroxide and embedded in epoxy resin using the routine methods. The ultrathin sections were cut with a diamond knife without decalcification. The sections were examined with the HITACHI H-800H type transmission electron microscope operated at 200 kV. Each crystal was observed at an initial magnification of 300,000 times and at a final magnification of 10,000,000 times and over. The material used for the observation by the scanning electron microscope was the fractured surface obtained from the carious enamel. The fractured carious enamel surfaces were coated with carbon and gold and observed with the HITACHI HHS-2R type scanning electron microscope operated at 25 kV. The crystals were observed at a final magnification of 50,000 times. As a result, we have confirmed that the dissolution of the enamel crystals caused by a caries occurs in the units of "hexagonal cell". We sincerely believe that the electron micrographs shown in this report are the first to show the images of the dissolution of the enamel crystals caused by a caries at near atomic resolution.

Dental Caries↗
PubMed2000

Meta-analysis of observational studies in epidemiology: a proposal for reporting. Meta-analysis Of Observational Studies in Epidemiology (MOOSE) group.

OBJECTIVE: Because of the pressure for timely, informed decisions in public health and clinical practice and the explosion of information in the scientific literature, research results must be synthesized. Meta-analyses are increasingly used to address this problem, and they often evaluate observational studies. A workshop was held in Atlanta, Ga, in April 1997, to examine the reporting of meta-analyses of observational studies and to make recommendations to aid authors, reviewers, editors, and readers. PARTICIPANTS: Twenty-seven participants were selected by a steering committee, based on expertise in clinical practice, trials, statistics, epidemiology, social sciences, and biomedical editing. Deliberations of the workshop were open to other interested scientists. Funding for this activity was provided by the Centers for Disease Control and Prevention. EVIDENCE: We conducted a systematic review of the published literature on the conduct and reporting of meta-analyses in observational studies using MEDLINE, Educational Research Information Center (ERIC), PsycLIT, and the Current Index to Statistics. We also examined reference lists of the 32 studies retrieved and contacted experts in the field. Participants were assigned to small-group discussions on the subjects of bias, searching and abstracting, heterogeneity, study categorization, and statistical methods. CONSENSUS PROCESS: From the material presented at the workshop, the authors developed a checklist summarizing recommendations for reporting meta-analyses of observational studies. The checklist and supporting evidence were circulated to all conference attendees and additional experts. All suggestions for revisions were addressed. CONCLUSIONS: The proposed checklist contains specifications for reporting of meta-analyses of observational studies in epidemiology, including background, search strategy, methods, results, discussion, and conclusion. Use of the checklist should improve the usefulness of meta-analyses for authors, reviewers, editors, readers, and decision makers. An evaluation plan is suggested and research areas are explored.

Epidemiology↗
PubMed1996

Assessment of left ventricular volume and mass by cine magnetic resonance imaging in patients with anterior myocardial infarction intra-observer and inter-observer variability on contour detection.

Remodeling of the left ventricle after myocardial infarction can be documented by calculation of left ventricular volume and mass, using endocardial and epicardial tracings of multilevel multiphase short-axis cine magnetic resonance (MR) imaging series. We assessed left ventricular volume and mass from 8 slices and during 12 phases of the cardiac cycle in seven patients with an anterior wall myocardial infarction; one patient was studied twice, leaving eight MR examinations to be evaluated. Purpose of this study was to assess the intra-observer and inter-observer variability of epicardial volume, endocardial volume, and left ventricular mass from contours manually traced by two independent observers. For the eight MR examinations, epicardial volume was found to be 292 +/- 51 ml (mean +/- SD) at end-diastole, which decreased to 237 +/- 55 ml at end-systole. Endocardial volume was 141 +/- 31 ml at end-diastole, which decreased to 79 +/- 27 ml at end-systole. Left ventricular ejection fraction was 45 +/- 8%. Mean left ventricular mass, when averaged over all patient studies and all phases, was 159 +/- 30 g. Intra-observer and inter-observer variability were found to be 3.5% and 5.2% for endocardial volume, 2.0% and 2.5% for epicardial volume, and 3.6% and 3.6% for left ventricular mass, respectively. The contour analysis showed a statistically significant phase effect in the endocardial contour in the midventricular slices, which was resolved after establishing a more precise definition for the tracing of the endocardial border. In conclusion, left ventricular volume and mass in patients with an anterior wall myocardial infarction can be assessed with high reproducibility and reliability from manual contour tracings. A precise protocol for the definition of endocardial and epicardial contours is required to obtain reproducible and reliable results.

Humans↗
PubMed2002

A prospective, observational study of a chest pain observation unit in a British hospital.

OBJECTIVES: To establish a chest pain observation unit, monitor its performance in terms of appropriate discharge after assessment, and estimate the cost per patient. METHODS: Prospective, observational, cohort study of patients attending a large, city, teaching hospital accident and emergency department between 1 March 1999 and 29 February 2000 with acute undifferentiated chest pain. Patients were managed on a chest pain observation unit, entailing two to six hours of observation, serial electrocardiograph recording, cardiac enzyme measurement, and, where appropriate, exercise stress test. Patients were discharged home if all tests were negative and admitted to hospital if tests were positive or equivocal. The following outcomes were measured-proportion of participants discharged after assessment; clinical status three days after discharge; cardiac events and procedures during the following six months; and cost of assessment and admission. RESULTS: Twenty three participants (4.3%) had a final diagnosis of myocardial infarction. All were detected and admitted to hospital. A total of 461 patients (86.3%) were discharged after assessment, 357 (66.9%) avoided hospital admission entirely. At review three days later these patients had no new ECG changes and only one raised troponin T measurement. In the six months after assessment, three cardiac deaths, two myocardial infarctions, and two revascularisation procedures were recorded among those discharged. The mean cost of assessment and hospital admission was 221 pound per patient, or 323 pound if subsequent interventional cardiology costs were included. CONCLUSIONS: The chest pain observation unit is a practical alternative to routine care for acute chest pain in the United Kingdom. Negative assessment effectively rules out immediate, serious morbidity, but not longer term morbidity and mortality. Costs seem to be similar to routine care.

Angina Pectoris↗