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At least 19 recordsLinked to original sources
PubMed1988

Inter-observer and intra-observer variability of the Oxford clinical cataract classification and grading system.

Intra-observer (within observers) and inter-observer (between observers) variability of the Oxford Clinical Cataract Classification and Grading System were studied. Twenty cataracts were examined and scored independently by four observers. On a separate occasion two of the observers repeated the assessments of the same cataracts in the absence of information from the initial observations. The chance corrected and weighted kappa statistics for observer agreement, both for inter-observer and intra-observer variability demonstrated satisfactory repeatability of the cataract grading system. The overall intra-observer mean weighted kappa was kappa w = +0.68 (range SE kappa = 0.012-0.052) and the overall inter-observer mean weighted kappa was kappa w = +0.55 (range SE kappa = 0.011-0.043).

Cataract↗
PubMed1986

Inter-observer and intra-observer variation in bone histomorphometry.

Inter-observer variation has been examined for a number of histomorphometric indices in 20 normal human iliac crest biopsies. Quantitation was performed using an eye-piece graticule and eye-piece micrometer. The same sections were examined by two observers and the methodology was identical. Intra-observer variation was also assessed. Significant inter-observer differences were found for the measurement of total trabecular bone volume, osteoid volume and surface, double plus single and double tetracycline labeled surfaces, and the mean osteoid seam width. The percentage variance due to inter-observer variation was highest for osteoid surface and volume, total resorption surface, and mean osteoid seam width. Intra-observer variation in both observers was small. We conclude that a large inter-observer variation may occur in the measurement of a number of histomorphometric indices, even when section preparation and methodology are identical. Caution should be used in basing the diagnosis of metabolic bone disease on strictly defined control data from other observers, particularly when this has been obtained from centers where the effects of inter-observer variation may be magnified by differences in methodology.

Bone Resorption↗
PubMed1997

Inter-observer and intra-observer agreement in the interpretation of visual fields in glaucoma.

Visual field changes are one of the main parameters used to monitor progression of glaucoma. This study assesses the degree of intra-observer and inter-observer agreement among nine observers in grading visual fields in glaucoma patients using a visual field system previously described by Jay. The results show a median inter-observer agreement of 61% (median kappa = 0.52) and a median intra-observer agreement of 72% (median kappa = 0.65). This system for grading fields in glaucoma has a high degree of intra-observer agreement, suggesting it is a useful system for longitudinal follow-up of patients by a single observer. The higher degree of disagreement between observers points to the need for careful pretraining of observers in clinical management and research where the results from visual field examinations are to be graded by more than one clinician.

Cohort Studies↗
PubMed1993

Intra-observer and inter-observer reliability of the pulsatility index calculated from pulsed Doppler flow velocity waveforms in three fetal vessels.

OBJECTIVE: Study of the intra observer and inter observer reliability of the pulsatility index, calculated from pulsed Doppler recordings of three fetal vessels. DESIGN: Flow velocity waveforms (FVW) were recorded from the umbilical artery, the fetal descending aorta and the fetal internal carotid artery. Intra-observer reliability was assessed in six fetuses; ten repeated measurements were performed by one observer. Inter-observer reliability was studied in 14 fetuses; two observers performed two repeated measurements in each fetus. SETTING: A tertiary referral hospital. SUBJECTS: High risk pregnancies with a gestational age ranging from 29 to 42 weeks. MAIN OUTCOME MEASURES: Analysis of variance with repeated measurements and a graphical method were used for data analysis. Intra-observer repeatability was expressed as Intraclass Correlation Coefficient (IntraCC). Inter-observer agreement was expressed as Interclass Correlation Coefficient (InterCC). RESULTS: IntraCC for umbilical artery, descending aorta and internal carotid artery were 0.91, 0.78, and 0.54, respectively. InterCC values for these vessels were 0.39, 0.45 and 0.34, respectively. No systematic differences between the two observers except for the fetal descending aorta, were apparent. IntraCC decreased remarkable when fetuses with absent end diastolic velocities were excluded from the analysis. CONCLUSION: The pulsatility index (PI) used for fetal measurements has a poor reliability. This is of serious concern when clinical use of FVW measurements is considered as a diagnostic tool.

Aorta, Thoracic↗
PubMed1987

[Modeled events and observers' traits underlying observational learning of altruistic behavior].

The present experiments investigated the changes of altruistic responses through observational learning (OL) in elementary school children (ages 10 and 11) with relation to the characteristics of the modeled events and the observers' traits. The former included certain categories of observed materials and the methods of presentation. The latter included subject's impression, empathy for, and evaluation of these materials. The OL was the symbolic modeling of altruistic behavior by presentation of pictures with narration. The response measures were the rating of pre- and post-questionnaires on the altruistic stories. The main result of Experiment I showed that subjects responded selectively to each pretest questionnaire, and that the observational learning was most effective on the similar kind of behavior type. The generalization of OL to other items of categories was also observed. In Experiment II, the combined effect of a pair of observed materials (positive or negative altruistic content) was examined. The effect of OL was highest when the material presented was a P-N pair, lowest when it was a N-N pair. The observers' traits in empathy, impression, and evaluation on observed materials were positively correlated to the effect of OL.

Altruism↗
PubMed1995

Intra-observer and inter-observer variability in scoring laparoscopic diagnosis of pelvic adhesions.

The objective of this study was to investigate intra-observer as well as inter-observer variability in the assessment of laparoscopic scoring of adhesive disease. Patients with suspected pelvic adhesions underwent a laparoscopic examination and surgical correction, using a standardized adhesion scoring system for severity as well as for extent of the adhesive process. An active agent or placebo was placed in the peritoneal cavity to discourage reformation of adhesions on a double-blind basis. A second laparoscopy was performed in 6-10 weeks and patients were re-scored. The videotapes were viewed and re-scored by the operator and four other gynaecological surgeons on two occasions, 3 months apart. Both adhesion severity and extent scores were lower following laparoscopic intervention. Reliability coefficients as defined by intra-class correlations were large indicating good reliability (0.778 and 0.758 for severity and extent respectively). Intra-observer (replication) variability was 12% of the total versus 19% for inter-observer variability of adhesion severity. These values were 15.4 and 22.3% of the total respectively, for adhesion extent. Individual observers tended to up-grade severity and minimize extent of adhesions when comparing the second with the first videotape views. The surgeon recorded greater adhesion score differences between the two procedures than the other observers. Though two physicians consistently had higher scores than two others, the intra-observer and interobserver variabilities were acceptable. Consultant review of high quality videotaped laparoscopic procedures is a valid method of independent assessment of operative findings.

Adnexal Diseases↗
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↗
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↗
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↗
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↗
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↗
PubMed1991

Using replicate observations in observer agreement studies with binary assessments.

By introducing replicate observations into observer agreement studies, one can obtain better measures of observer agreement than heretofore possible. New methodology based on the analysis of latent variables allows a separation of within- and between-observer variation for binary measures of assessment among pairs of observers. Maximum likelihood estimation and hypothesis testing are discussed. The methodology is illustrated using data on the assessment of dysplasia by pathologists.

Biometry↗