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PubMed1997

Accuracy of radiographic diagnosis of peri-implant radiolucencies--an in vitro experiment.

The absence of a peri-implant radiolucency on radiographs is used as a criterion for implant success. The purpose of the present study was to evaluate the accuracy of diagnosing peri-implant radiolucencies using an experimental model. Astra Tech fixtures were inserted into 20 bony specimens. Later, the fixtures were removed and the prepared cavities were enlarged in 2 steps. The specimens were radiographed under strictly standardized circumstances in the 3 stages ("press-fit" = simulated osseointegration, and "0.1 mm space" and "0.175 mm space" = simulated connective tissue layer). All specimens were radiographed with 2 vertical angulations (0 degree and 15 degrees). Ten observers read the radiographs and evaluated bone-implant relationship on a 5-point scale. The interobserver agreement was low. Specificity was remarkably low, and sensitivity was moderate. A significant difference in diagnostic accuracy was found for 0.175 mm peri-implant-space compared to 0.1 mm space. The diagnostic accuracy was found to be highest for 0.175 mm peri-implant space specimens. It is concluded, that radiography seems to be an unreliable method for diagnosing peri-implant spaces, although accuracy improved at increasing space widths. Strict orthogonal projection angles did not improve diagnostic accuracy.

Alveolar Bone Loss↗
PubMed1987

Accuracy of person perception: do people know what kinds of impressions they convey?

Do people know what kinds of impressions they convey to other people during particular social interactions? In a study designed to answer this question, subjects interacted individually with three partners on each of four different tasks. After each interaction, participants reported their impressions of the other person's likability and competence. They also postdicted the impressions they believed they conveyed to the other person along the same dimensions. Accuracy was computed as recommended by Cronbach (1955) and by Kenny's (1981) Social Relations Model. Subjects could tell to a significant degree how the impressions they conveyed to their partners changed over time (time accuracy) and how they changed over time in different ways with different partners (differential accuracy). They could also tell how their competence was differentially perceived by different partners (dyadic accuracy). However, they were not very accurate at discerning which partners perceived them as most competent or most likable across all interactions (person accuracy). Subjects believed that they conveyed similar impressions of themselves to all of their partners, although actually partners evidenced little agreement with each other in their impressions of a given subject. The implications of these findings for symbolic-interactionist theories of the development of the self and impression-management perspectives on social behavior are described.

Humans↗
PubMed1997

Reaction time and assessments of cognitive effort as predictors of eyewitness memory accuracy and confidence.

The authors investigate reaction time, subjective assessments of memory processing, and confidence as predictors of memory for the details of a crime. The authors also examine the mediation of a previously identified difference between recognition tasks and recall tasks in the correlation between confidence and accuracy. College undergraduates (n = 111) answered either recognition or recall questions. Reaction time and subjective assessments of cognitive effort were both negatively related to confidence and accuracy. Subjective assessments, however, were superior predictors of confidence, whereas reaction time was a unique predictor of accuracy. The reaction time-confidence and reaction time-accuracy correlations were stronger under recall conditions than under recognition conditions. Multiple regression results suggested a possible explanation for the superior insight of recall participants into memory accuracy.

Adult↗
PubMed1993

Definition and assessment of accuracy in social stereotypes.

A perennial issue in the study of social stereotypes concerns their accuracy. Yet, there is no clear concept of the various ways in which stereotypes may be accurate or inaccurate and how one would assess their accuracy. This article is designed to rectify this situation. Three forms of stereotype inaccuracy are identified: stereotypic inaccuracy, valence inaccuracy, and dispersion inaccuracy. The implications of each form are discussed, along with how each can be assessed using a full-accuracy design. Past research that has attempted to examine stereotype accuracy is reviewed, and new data on the issue are presented. Although of perennial interest, the theoretical and methodological difficulties of assessing stereotype accuracy are substantial. The goal in this article is to alert the researcher to these difficulties and point toward their solution.

Humans↗
PubMed2000

Influence of body composition on the accuracy of reported energy intake in children.

OBJECTIVE: Mis-reporting dietary intake is a substantial barrier to understanding the role of dietary behavior in disease. Work with adults indicates that heavier individuals under-report dietary intake and that under-reporting may be macronutrient-specific. Whether weight status and macronutrient intake influence the accuracy of dietary reports among children, however, is less clear. This research evaluated children's dietary reporting accuracy as a function of their relative weight, body composition, and macronutrient intake. RESEARCH METHODS AND PROCEDURES: Participants included 146 4- to 11-year-old children. Reported energy intake was determined by interviewing children in the presence of parents, using three multiple pass, 24-hour recalls. Children were classified as having had an under-reported, accurately reported, or over-reported dietary intake relative to total energy expenditure, as measured by doubly labeled water. Reporting accuracy was examined as a function of children's body weight, body composition (using dual energy x-ray absorptiometry), and macronutrient intake. RESULTS: Average reported intake was, on average, 14% greater than children's estimated expenditure (p < 0.01). Reporting accuracy varied as a function of children's relative weight and body composition; under-reporting tended to occur among heavier children, having the highest body fat content (p < 0.0001) and relative weight (p < 0.0001). DISCUSSION: These findings suggest that weight status influences the accuracy of dietary reports made by children and their parents. More research is needed to address possible psychological and social factors that introduce bias in reporting children's dietary data.

Absorptiometry, Photon↗
PubMed2002

Accuracy of caries detection with four storage phosphor systems and E-speed radiographs.

OBJECTIVE: To evaluate the accuracy of caries detection using four intra-oral storage phosphor plate systems exposed with two different exposure times and one film system. METHODS: Under in vitro and standardised conditions 365 approximal and 159 occlusal surfaces were radiographed using four storage phosphor plate systems: DenOptix, Cd-dent, Digora (blue and white plates) and one film system: Ektaspeed Plus. The plates were exposed twice with 10% and 25% of the time needed for the film. Four observers recorded approximal enamel/dentine and occlusal dentine caries using a five-point confidence scale. Caries presence was validated histologically and diagnostic accuracy of the systems by using ROC curve areas (Az). RESULTS: The shorter exposure time for approximal caries, Digora(white)(Az=0.68) and Ekta Plus (Az=0.69) were significantly more accurate than the other systems (Az=0.64-0.65). For occlusal caries using the same exposure time, no significant difference was found between the digital systems (Az=0.76-0.77), which all showed to be significantly less accurate than Ekta Plus (Az=0.81). Using the longer exposure time for approximal caries, no significant difference was found between DenOptix (Az=0.68), Digora(blue) (Az=0.69), Digora(white) (Az=0.69) and Ekta Plus (Az=0.69) which were all significantly more accurate than Cd-dent (Az=0.65). For occlusal caries using the same exposure time, Digora(blue) (Az=0.81) was the most significantly accurate of the digital systems. When approximal caries was the diagnostic task, the longer exposure time resulted in significantly higher accuracy with the DenOptix and Digora(blue) systems but not with the Cd-dent and Digora(white) systems. For occlusal caries, the longer exposure time resulted in a significant improvement only with the Digora(blue) system. CONCLUSION: For approximal caries using the longer exposure time, no significant difference in diagnostic accuracy was found between DenOptix, Digora(blue), Digora(white) and Ekta Plus which were all significantly more accurate than the Cd-dent. For occlusal caries using the longer exposure time, Digora(blue) was found to be the most accurate of the digital systems. The exposure time had an influence on the diagnostic accuracy with the DenOptix and Digora(blue) systems for approximal and with the Digora(blue) system for occlusal caries detection.

Area Under Curve↗
PubMed2003

Delayed predictive accuracy of narrative recall after traumatic brain injury: salience and explicitness.

Fifteen adults with traumatic brain injury (TBI) and 15 adults without brain injury listened to narratives, made delayed predictions of recall, and took a delayed recall test. Narrative questions differed by salience (main ideas, details) and explicitness (implied, stated) (R. H. Brookshire & L. E. Nicholas, 1993). TBI survivors recalled less than control participants regardless of question type. All participants recalled main ideas and implied information with greater accuracy than details and stated information. Predictive accuracy for recalling stated information was strong regardless of group. Participants were unable to predict recall for implied information. The materials-appropriate-processing (MAP) hypothesis proposes that predictive accuracy is biased by text type (i.e., predictive accuracy for recalling main ideas should be higher than for details when learning narratives). However, there were no differences in predictive accuracy for recalling main ideas and details, with both groups predicting recall modestly well. Controlling for explicitness appears to be an important variable for future metamemory text studies.

Adult↗
PubMed2001

Accuracy of emergency department bedside ultrasonography.

OBJECTIVES: To determine which focused ultrasound examinations can be interpreted accurately by emergency physicians who have limited training and experience. To determine whether image quality and/or the operator's level of confidence in the findings correlates with accurate scan interpretation. METHODS: A prospective sample of consenting adult emergency department patients with the conditions was selected for study. Scans were performed by emergency physicians who had attended a 3-day focused ultrasound examinations instruction course. All scans were videotaped and subsequently reviewed by a radiologist. Accuracy was determined by comparing the emergency physicians scan interpretation with preselected gold standards. Chi-squared tests were employed to determine if the individual performing the scan, the type of scan, patient's body habitus, image quality and/or operator confidence were reliable predictors of accuracy. RESULTS: Between September 1997 and January 1999, 221 scans were studied. Accuracy varied widely depending on the type of scan performed: aortic scans were 100% accurate whereas renal scans had 68% accuracy. On bivariate analyses, there was little variation in the various operators' levels of proficiency and accuracy of interpretation was not associated with patient body habitus, image quality or operator confidence. CONCLUSIONS: Neophytes can accurately perform and interpret aortic scans; additional training and/or experience appear to be necessary to achieve proficiency in conducting most of the other scans studied. Inexperienced operators are unable to discern whether their scan interpretations will prove accurate.

Adult↗
PubMed2002

The accuracy of clinical diagnosis of suspected premalignant and malignant skin lesions in renal transplant recipients.

Renal transplant recipients have a greatly increased risk of nonmelanoma skin cancer. We investigated the accuracy of diagnosis of suspected skin malignancies in this population by prospectively recording all lesions detected in a specialist clinic over 5 months and comparing the provisional diagnosis with the histological diagnosis. The diagnostic accuracy was 54% in the 102 lesions that were biopsied, with the highest accuracy for the head and neck (67%). The diagnostic accuracy for squamous cell carcinoma was 48.7% (sensitivity 90.5%, specificity 75.3%) and for basal cell carcinoma 40.0% (sensitivity 66.6%, specificity 85.6%). The overall low accuracy rate implies the need for biopsy of any suspicious lesions in the renal transplant population.

Aged↗
PubMed1998

The treatment of pressure sores: a comparison of novice and expert nurses' knowledge, information use and decision accuracy.

The knowledge experts have and the way it is organized is thought to affect their decision accuracy and the information they use to make decisions. This exploratory study examines the information used by experts, the way they organize their knowledge and their decision accuracy when considering treatments for pressure sores. A convenience sample of 14 subjects (seven experts and seven novices) were given a card sorting task and a decision task. The cards for the sort contained photographs of pressure sores and various dressings, which the subjects had to place into meaningful categories. In the decision task they were given a photograph of a pressure sore, together with various items of information which could be used to make a decision about the appropriate treatment for the pressure sore. The accuracy of the subjects' decisions were compared to a 'gold standard' decision formulated by an expert panel. Results indicated that experts were more accurate in their choice of treatments in the decision task, and also focused on specific items of information to make their decisions. The accuracy of their decisions was not linked to the categorization strategy used in the card sorts. The findings from this study indicate that more research into the way in which such treatment decisions are undertaken needs to be carried out. Specifically, the way in which education into wound care treatments affects decision accuracy needs to be identified, and ways of aiding individuals to focus on relevant information explored.

Adult↗
PubMed2002

Accuracy of check-bite registration and centric condylar position.

In a dentate subject a jaw relation can either be determined in maximum intercuspation and is as such given by the occlusal morphology, or the mandibular position can be allocated according to the centric position of the condyles. For comprehensive restorative treatment or analytic measures of the occlusion it is important to record the centric condylar position. Various registration methods have been described in the literature, but there is no consensus on which is the 'best'. The aim of the present study was therefore to assess the accuracy of various registration methods and evaluate a possible influence of the used materials. Four dentists were involved in the clinical part of the study, another was responsible for the measurements. Impressions were taken from 81 fully dentate volunteers. The casts were mounted by face-bow transfer and central-bearing-point (CBP) registration into Dentatus articulators. Subsequently the centric condylar position was determined with six different methods and materials, respectively. Each method was reproduced twice so that a total of 18 registrations was performed per patient. The mandibular positions which resulted from the individual registrations were then repeatedly compared in the condylar area using a computer supported specially modified measuring articulator. The accuracy was found best for the unrefined wax wafer registration (x=0.33 mm) and with an average of 0.44 mm worst when using acrylic wafers. The CBP and frontal jig methods as well as tin-foil and refined wax wafers showed an accuracy in-between these boundaries. The biggest measured mandibular displacement between any two registrations were considerably 2.0 mm. However, the described differences in accuracy between the various methods and materials proved statistically not significant. All investigated jaw registrations showed an accuracy of about 20 times the tactile fine sensibility of natural teeth which has to be taken into account when inserting fixed prosthetic restorations in centric condylar position. Despite meticulous clinical and technical procedures small occlusal adjustments are therefore almost unavoidable.

Acrylic Resins↗
PubMed2000

Representation of accuracy in the dorsal premotor cortex.

The endpoint accuracy of a reaching movement strongly affects kinematics, particularly during the final phases of movement. However, where and how accuracy is represented in the central nervous system remains unknown. In this study, the discharge of 150 neurons located primarily in the dorsal premotor cortex (PMd), were recorded from monkeys performing an instructed delay, centre-out reaching task in which movement direction and target size were systematically varied. Linear regression analyses were used to assess the dependence of movement kinematics and cell discharge on target direction, size and tangential velocity (i.e. speed). The speed and timing of the movement were dependent on both direction and target size. Initially direction was the dominant predictor whilst target size became more important as the hand reached the target. A temporal multiple linear regression analysis found significant correlations with target size in 99 of 150 cells. The discharge of 134 cells was directionally tuned and 83 cells modulated with mean speed. Significant correlations of discharge with target size occurred throughout the task as did correlations with direction. However, correlations with direction preferentially occurred early in the task, prior to movement onset, whilst correlations with target size tended to occur late, well after movement onset. This temporal dependency of the firing in relationship to target direction and size mirrored that observed for the kinematics. We conclude that the discharge of PMd cells is highly correlated with the accuracy requirement of the movement. The timing of the correlations suggest that accuracy information is available for the planning and for the on-line control of endpoint accuracy.

Action Potentials↗
PubMedDate not supplied

Accuracy of frozen section diagnosis in ovarian tumors: Is there a change in the course of time?

A retrospective study of 222 ovarian biopsy results between January 1, 2000 and August 31, 2002 was examined to determine the accuracy of frozen section diagnosis. In addition we reviewed all previous studies that examined the accuracy rates of frozen section diagnosis in ovarian tumors. Histopathologic examination results of frozen section biopsies were concordant with paraffin diagnosis in 92% of all cases. The sensitivity rates for benign, malignant, and borderline ovarian tumors were 98%, 88.7%, and 61%, respectively. There were five (2.2%) false-positive (overdiagnosed), and 13 (5.4%) false-negative (underdiagnosed) patients in frozen section examination. Frozen section examination of mucinous tumors showed higher underdiagnosis rates (20%). Review of previous studies showed no significant variation in accuracy rates of frozen section diagnosis for benign and malignant ovarian tumors, in relation with time. We found low accuracy rates for borderline ovarian tumors which was similar with the previous studies. However, there were consistent and relatively higher sensitivity rates for borderline ovarian tumors in the recent studies. As a result, we conclude that frozen section evaluation in identifying a malignant or benign ovarian tumor is accurate enough for the correct diagnosis. Since accuracy rates for borderline ovarian tumors are low, we should have more improvement in the correct diagnosis.

Adenocarcinoma, Clear Cell↗
PubMed1999

Impact of a clinical scenario on accuracy of electrocardiogram interpretation.

To examine the effect of clinical history on the electrocardiogram (ECG) interpretation skills of physicians with different levels of expertise, we randomly allocated to an ECG test package 30 final-year medical students, 15 second-year internal medicine residents, and 15 university cardiologists at university-affiliated teaching hospitals. All participants interpreted the same set of 10 ECGs. Each ECG was accompanied by a brief clinical history suggestive of the correct ECG diagnosis, or the most plausible alternative diagnosis, or no history. Provision of a correct history improved accuracy by 4% to 12% compared with no history, depending on level of training. Conversely, a misleading history compared with no history reduced accuracy by 5% for cardiologists, 25% for residents, and 19% for students. Clinical history also affected the participants' frequencies of listing ECG features consistent with the correct diagnosis and features consistent with the alternative diagnosis (all p values < .05). For physicians at all levels of expertise, clinical history has an influence on ECG diagnostic accuracy, both improving accuracy when the history suggests the correct diagnosis, and reducing accuracy when the history suggests an alternative diagnosis.

Adult↗
PubMed2003

Accuracy of whole-body 18F-FDP-PET for restaging malignant lymphoma.

BACKGROUND: The aim of this retrospective study was to evaluate the accuracy of fluorine-18 fluorodeoxyglucose positron emission tomography (18F-FDG-PET) images, which were interpreted under daily routine conditions, in patients with Hodgkin's disease (HD) or non-Hodgkin lymphoma (NHL) for restaging after chemotherapy and/or radiotherapy. For this purpose, 18F-FDG-PET results were compared with morphological imaging methods and the patients' clinical background. METHODS: 121 PET images of 93 lymphoma patients (44 HD, 49 NHL) were investigated after chemotherapy/radiotherapy. For PET imaging, 160-200 MBq 18F-FDG was administered intravenously, followed by an infusion of 20 mg Furosemid in 250 mL saline. Whole-body 18F-FDG-PET images were obtained using a partial-ring PET scanner without attenuation correction. The morphological imaging consisted in computed tomography and ultrasound (CT/US) in all patients, additional MRI in some patients, and iliac crest biopsy in cases of suspicious bone marrow involvement. The standard of reference was composed of biopsy data, clinical status at the time of investigation, and follow-up of at least 12 months. The PET images were evaluated for their sensitivity, specificity and accuracy based on written reports, which were compiled from other imaging data and the clinical history of the patients. RESULTS: Sensitivity, specificity, and accuracy of 18F-FDG-PET was 91 %, 81 %, and 85 %; of CT/US, 88 %, 35 %, 56 %, respectively. Major sources of error in 18F-FDG-PET were due to asymmetric muscular hypermetabolism and inflammatory lesions misinterpreted as persistent viable lymphoma tissue. Furthermore, secondary malignancies other than lymphomas were another reason for misinterpretations of 18F-FDG-PET studies. CONCLUSIONS: 18F-FDG-PET showed a comparable sensitivity but a higher specificity and accuracy compared with CT/US. To achieve a high accuracy in 18F-FDG-PET, the nuclear medicine specialist needs imaging and clinical data as background information, which can only be acquired through close co-operation with the referring clinicians. Pharmacological muscular relaxation in the course of 18F-FDG-PET imaging may be advisable, as nonspecific muscular hypermetabolism was one of the problems at the image readings and a source of incorrect 18F-FDG-PET interpretations.

Adolescent↗
PubMed2000

The comparative accuracy of radiolucent foreign body detection using ultrasonography.

The purpose of this prospective study was to determine the accuracy of ultrasonography in detecting radiolucent foreign bodies and to compare the performance of three newly trained emergency physicians with two experienced ultrasound technologists and one radiologist. One hundred-four chicken thighs were penetrated with a needle-driver, half of them embedded with a 1.5 cm toothpick. An 8.0 MHZ linear array ultrasound probe was used to detect the presence or absence of the foreign body. The overall accuracy (95% confidence interval [CI]) was 82% (79, 85); sensitivity 79% (74, 83), specificity 86% (82, 90), positive predicative value (PPV) 85% (81, 89), and negative predicative value (NPV) 80% (76, 84). The accuracy (95% CI) of the radiologist was 83% (75, 90); of the ultrasound technologists was 85% (80, 90); and of the emergency physicians was 0% (76, 85). The difference in accuracy among the three types of personnel was not statistically significant. Ultrasonography is an accurate modality in detecting radiolucent foreign bodies. Emergency physicians can be trained to provide a degree of accuracy comparable with more experienced ultrasonographers.

Allied Health Personnel↗
PubMed2000

Clinician judgments of functional outcomes: how bias and perceived accuracy affect rating.

OBJECTIVE: To evaluate the accuracy of clinician judgments of patient function, the susceptibility of judges to bias, and the relation between a judge's degree of belief in his/her accuracy of classification to observed accuracy when using the FIM instrument. PARTICIPANTS: Fifty rehabilitation professionals. SETTING: 3 urban medical centers. DESIGN: Four randomized experiments among subjects to examine the effect of potentially biasing information on FIM ratings of patient vignettes. Participants answered 60 true/false questions regarding patient function and FIM score and indicated confidence in the accuracy of their answers. INTERVENTIONS: Manipulation of patient information. MAIN OUTCOME MEASURES: The standard FIM 7-point scale, observed proportion of correct responses to the 60 true/false questions, and a 6-category confidence scale for each of the 60 questions were used as dependent measures. RESULTS: FIM ratings assigned to others biased participants' FIM ratings of patient vignettes. Functional ability was overestimated when ratings in other domains were high and underestimated when they were low. Participants were overconfident in their ability to answer FIM questions accurately across all professional disciplines. CONCLUSION: Bias and poor judgment of level accuracy play a significant role in clinician ratings of patient functioning. Blind ratings and training in debiasing are potential solutions to the problem.

Activities of Daily Living↗
PubMed2003

The accuracy of video imaging prediction in soft tissue outcome after bimaxillary orthognathic surgery.

PURPOSE: The purpose of the present study was to evaluate the accuracy of the outcome in soft tissue prediction through use of a computer imaging system after bimaxillary orthognathic surgery. MATERIALS AND METHODS: The study sample consisted of 30 adults who had undergone orthognathic surgery that included the Wassmund and Köle procedures and optional genioplasty to correct bimaxillary protrusion. All the patients had lateral cephalometric radiographs and profile photographs taken within 6 months before surgery and at least 6 months after surgery. The computer-generated soft tissue image and the actual postsurgical profile were compared. The accuracy of this computer-generated profile image was evaluated. RESULTS: The results indicated that the nasal tip, soft tissue A point, and upper lip presented the least predicted errors in sagittal plane. While the nasal tip presented higher reliability. Lower lip prediction was found to be the least accurate region and it tended to be located anterior to the actual position. In the vertical plane, most of the predictions revealed higher accuracy than those in the sagittal plane. There were no statistically significant differences between the predictions of the groups with and those without genioplasty. CONCLUSIONS: Computer-generated image prediction was suitable for patient education and communication. However, efforts are still needed to improve the accuracy and reliability of the prediction program and to include the consideration of changes in soft tissue tension and muscle strain. The accuracy of this system in soft tissue prediction should be carefully interpreted.

Adult↗