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PubMed2002

Accuracy of needle placement into the intra-articular space of the knee.

BACKGROUND: To achieve their potential therapeutic benefit, hyaluronic acid derivatives should be injected directly into the knee joint space and not into the anterior fat pad or the subsynovial tissues. In the absence of a knee effusion, reproducible needle placement into the intra-articular space presents a challenge to the clinician. METHODS: The accuracy of needle placement was assessed in a prospective series of 240 consecutive injections in patients without clinical knee effusion. The injections were performed by one orthopaedic surgeon using a 2.0-in (5.1-cm) 21-gauge needle through three commonly employed knee joint portals: anteromedial, anterolateral, and lateral midpatellar. Accuracy rates for needle placement were confirmed with fluoroscopic imaging to document the dispersion pattern of injected contrast material. RESULTS: Of eighty injections performed through an anterolateral portal, fifty-seven were confirmed to have been placed in the intra-articular space on the first attempt (an accuracy rate of 71%). Sixty of eighty injections performed through an anteromedial approach were intra-articular on the first attempt (75% accuracy rate), as were seventy-four of eighty injections performed through a lateral midpatellar portal (93% accuracy rate). CONCLUSIONS: Using real-time fluoroscopic imaging with contrast material, we demonstrated the difficulty of accurately placing a needle into the intra-articular space of the knee when an effusion is not present. This study revealed that a lateral midpatellar injection (an injection into the patellofemoral joint) was intra-articular 93% of the time and was more accurate than injections performed by the same orthopaedic surgeon using either of the other two portals. This study highlights the need for clinicians to refine injection techniques for delivering intra-articular therapeutic substances that are intended to coat the articular surfaces of the knee joint.

Adjuvants, Immunologic↗

PubMed2005

Diagnostic accuracy of a new clinical test (the Thessaly test) for early detection of meniscal tears.

BACKGROUND: Clinical tests used for the detection of meniscal tears in the knee do not present acceptable diagnostic sensitivity and specificity values. Diagnostic accuracy is improved by arthroscopic evaluation or magnetic resonance imaging studies. The objective of this study was to evaluate the diagnostic accuracy of a new dynamic clinical examination test for the detection of meniscal tears. METHODS: Two hundred and thirteen symptomatic patients with knee injuries who were examined clinically, had magnetic resonance imaging studies performed, and underwent arthroscopic surgery and 197 asymptomatic volunteers who were examined clinically and had magnetic resonance imaging studies done of their normal knees were included in this study. For clinical examination, the medial and lateral joint-line tenderness test, the McMurray test, the Apley compression and distraction test, the Thessaly test at 5 degrees of knee flexion, and the Thessaly test at 20 degrees of knee flexion were used. For all clinical tests, the sensitivity, specificity, false-positive, false-negative, and diagnostic accuracy rates were calculated and compared with the arthroscopic and magnetic resonance imaging data for the test subjects and the magnetic resonance imaging data for the control population. RESULTS: The Thessaly test at 20 degrees of knee flexion had a high diagnostic accuracy rate of 94% in the detection of tears of the medial meniscus and 96% in the detection of tears of the lateral meniscus, and it had a low rate of false-positive and false-negative recordings. Other traditional clinical examination tests, with the exception of joint-line tenderness, which presented a diagnostic accuracy rate of 89% in the detection of lateral meniscal tears, showed inferior rates. CONCLUSIONS: The Thessaly test at 20 degrees of knee flexion can be used effectively as a first-line clinical screening test for meniscal tears, reducing the need for and the cost of modern magnetic resonance imaging methods.

Adolescent↗

PubMed2000

Effects of throwing overweight and underweight baseballs on throwing velocity and accuracy.

The purpose of this review is to determine how throwing overweight and underweight baseballs affects baseball throwing velocity and accuracy. Two studies examined how a warm-up with overweight baseballs affected throwing velocity and accuracy of 5 oz regulation baseballs. One of these studies showed significant increases in throwing velocity and accuracy, while the other study found no significant differences. Three training studies (6 to 12 weeks in duration) using overweight baseballs were conducted to determine how they affected ball accuracy while throwing regulation baseballs. No significant differences were found in any study. From these data it is concluded that warming up or training with overweight baseballs does not improve ball accuracy. Seven overweight and 4 underweight training studies (6 to 12 weeks in duration) were conducted to determine how throwing velocity of regulation baseballs was affected due to training with these overweight and underweight baseballs. The overweight baseballs ranged in weight from 5.25 to 17 oz, while the underweight baseballs were between 4 and 4.75 oz. Data from these training studies strongly support the practice of training with overweight and underweight baseballs to increase throwing velocity of regulation baseballs. Since no injuries were reported throughout the training studies, throwing overweight and underweight baseballs may not be more stressful to the throwing arm compared to throwing regulation baseballs. However, since currently there are no injury data related to throwing overweight and underweight baseballs, this should be the focus of subsequent studies. In addition, research should be initiated to determine whether throwing kinematics and kinetics are different between throwing regulation baseballs and throwing overweight and underweight baseballs.

Animals↗

PubMed1998

Accuracy of CT-guided needle biopsy of musculoskeletal neoplasms.

OBJECTIVE: The purpose of our study was to assess the accuracy of CT-guided biopsy of musculoskeletal neoplasms with respect to technique, anatomic site, and histology. MATERIALS AND METHODS: During a 3-year period (January 1992 to December 1994), 176 core needle biopsies and 45 fine-needle aspirations were performed under CT guidance on patients with musculoskeletal neoplasms. To assess the accuracy of these procedures, we compared the diagnosis at biopsy with the final diagnosis as determined at the time of definitive treatment of the lesion. All biopsy findings were categorized as a primary malignancy (excluding round cell lesions), round cell lesion, local recurrence, or metastatic carcinoma. In addition, each lesion was analyzed according to which biopsy technique was used, whether frozen tissue section or rapid cytologic evaluation was used, and at which anatomic site the mass was found. RESULTS: The accuracy for needle biopsy was 93% and that for fine-needle aspiration was 80%. The complication rate for both techniques was less than 1%. Accuracy rates for the four categories of primary malignancy, round cell lesion, local recurrence, and metastatic carcinoma were 87%, 75%, 94%, and 100%, respectively. The mismatch rates were similar in soft-tissue lesions (5/52) and bone lesions (16/169). Diminished accuracy was associated with round cell lesions (20%) and lesions located in the spine or the perivertebral region (20%). Nondiagnostic and insufficient specimens were found in 18 (8%) of the 221 patients. CONCLUSION. CT-guided biopsy of musculoskeletal malignancies is a safe and effective procedure if performed by a team of clinicians, pathologists, and radiologists who possess subspecialty expertise.

Biopsy, Needle↗

PubMed2000

Evaluation of the accuracy of gadobenate dimeglumine-enhanced MR imaging in the detection and characterization of focal liver lesions.

OBJECTIVE: We evaluated the extent to which hepatic lesion characterization and detection is improved by using gadobenate dimeglumine for enhancement of MR images. MATERIALS AND METHODS: Eighty-six patients were imaged before gadobenate dimeglumine administration, immediately after the 2 mL/sec bolus administration of a 0.05 mmol/kg dose (dynamic imaging), and at 60-120 min after the IV infusion at 10 mL/min of a further 0.05 nmol/kg dose (delayed imaging). The accuracy for lesion characterization was assessed for a total of 107 lesions. Sensitivity for lesion detection was assessed for a total of 149 lesions detected on either intra-operative sonography, iodized oil CT, CT during arterial portography, or follow-up contrast-enhanced CT as the gold standard. RESULTS: The accuracy in differentiating benign from malignant liver lesions increased from 75% and 82% (the findings of two observers) on unenhanced images alone, to 89% and 80% on dynamic images alone (p<0.001, p = 0.8), and to 90.7% when combining the unenhanced and dynamic image sets (p<0.001, p = 0.023). Delayed images did not further improve accuracy (90% and 91%; p = 0.002, p< 0.05). A similar trend was apparent in terms of accuracy for specific diagnosis: values ranged from 49% and 62% on unenhanced images alone, to 76% and 70% on combined unenhanced and dynamic images (p<0.001, p = 0.06), and to 75% and 70% on inclusion of delayed images (p<0.001, p = 0.12). The sensitivity for lesion detection increased from 77% and 81% on unenhanced images alone, to 87% and 85% on combined unenhanced and dynamic images (p = 0.001, p = 0.267), and to 92% and 89% when all images were considered (p<0.001, p = 0.01). CONCLUSION: Contrast-enhanced dynamic MR imaging with gadobenate dimeglumine significantly increases sensitivity and accuracy over unenhanced imaging for the characterization of focal hepatic lesions, and delayed MR imaging contributes to the improved detection of lesions.

Adult↗

PubMed2002

Accuracy of interpretation of CT scans: comparing PACS monitor displays and hard-copy images.

OBJECTIVE: The purpose of this study was to determine the relative diagnostic accuracy of radiologists in the interpretation of CT scans using a computer workstation in comparison with using film. MATERIALS AND METHODS: Four board-certified radiologists with extensive soft-copy experience interpreted 117 CT scans in four anatomic regions using films displayed on an alternator and images displayed on a four-monitor workstation. The radiologists were asked to interpret the scans in their usual fashion and were aware that both the time required to review the study and the accuracy of the reports were being assessed. The radiologists' diagnostic impressions were compared with those of a consensus panel and scored for accuracy. RESULTS: Soft-copy interpretation using computer workstations was found to produce statistically significant improvement in combined measurements of sensitivity, specificity, and overall accuracy for chest, brain, and chest-abdominal CT scans compared with film interpretation. CONCLUSION: PACS (picture archiving and communication system) offers radiologists the potential for improved accuracy in CT interpretation compared with traditional film-based interpretation.

Brain↗

PubMed1979

Comparison of accuracy in auditory and tactile recognition memory for environmental stimuli.

Accuracy rates for auditory and tactile recognition of naturalistic stimuli over a 7-day period are compared. 40 subjects listened to 50, 107, or 194 naturalistic sounds and were tested immediately or after delays of 2 or 7 days. 30 other subjects handled but did not visually inspect 150 common objects and were tested over the same three delay intervals. Recognition accuracy for sounds was 87.5%, 82.5%, and 80.4% while common objects were recognized at 96.0%, 93.8%, and 88.5% rates of accuracy. Tactile recognition memory was superior to auditory recognition memory. The recognition accuracies of both modalities were affected by the delay interval. The number of items inspected had no effect on the recognition memory for sounds. Following a delay of 1 wk., the accuracy of recognition relative to the original level of function was 92% for both modalities.

Auditory Perception↗

PubMed1995

Factors affecting accuracy of producing time intervals.

The present study assessed the accuracy of producing time intervals. 92 subjects were asked to produce three different time intervals (15, 30, and 60 sec.) under six experimental conditions during which they performed concurrent tasks of different cognitive difficulty and requiring different cognitive functions. Real-life working situations guided the design of the experiment. Accuracy of time estimation was significantly affected by the length of the intervals to be produced and the concurrent tasks performed. 15-sec. intervals were more accurately estimated. Accuracy decreased as the cognitive demands of the concurrent tasks increased; subjects systematically overestimated the duration of the intervals. Having an activity requiring time estimation seems to have a positive effect on the accuracy of time estimation. The same was found for certain strategies aiding time estimation which were used spontaneously by certain subjects. No significant difference in the accuracy of estimation between women and men was found.

Adult↗

PubMed1997

Speed and accuracy in the learning of a complex motor skill.

The effect of emphasizing speed or accuracy on the learning of a high speed-high accuracy skill, the fastpitch softball pitch was investigated. 26 10- and 11-yr.-old girls were randomly assigned to two groups receiving feedback on speed of throwing or accuracy of throwing during a 6-wk. training. Measurements of speed and accuracy were made and recorded on all participants at each practice session and a videotape of their pitching technique was also made at each session. Data were subjected to 2 x 3 (2 groups by 3 testing times) repeated-measures analyses of variance. The speed group threw faster and with better technique during the study and was able to maintain speed and accuracy in the reversed test condition.

Analysis of Variance↗

PubMed1998

Accuracy characteristics of throwing as a result of maximum force effort.

Fitts' law predicts the accuracy of movement to a target decreases as the velocity of the movement increases. This speed-accuracy tradeoff has been examined under numerous conditions. During some tasks, however, increased force to nearly maximal level decreases the variability of the movement (Sherwood & Schmidt, 1980). This condition apparently produced results different from what would be predicted by Fitts' law. The purpose of the present study was to examine the effects of maximal force on dart throwing accuracy and variability. 54 subject were categorized into groups based upon their experience with dart throwing: Advanced, Intermediate, or Beginners. Each subject performed two sessions of 15 trials. Subjects were instructed to "throw normally" for one session and "throw as hard as you can" for the other session Distances from the target (triple-20 area) on the regulation dart board were measured and recorded after each of three darts was thrown. Average Error and Variable Error were calculated for each condition for each subject. The Average Error and Variable Error were greatest for the Beginner group and least for the Advanced group. For all three experience categories both Average Error and Variable Error were significantly greater when subjects performed with maximal force. The greater average error for the maximal force for all subjects suggested that the speed-accuracy tradeoff applied to this aiming task. The greater variability in accuracy with maximal force suggested a ceiling effect, which reduced variability in previous studies, was not achieved.

Adult↗

PubMed2000

Decrement in the horizontal-vertical illusion: are subjects aware of their increased accuracy?

47 subjects adjusted the extended vertical lines of 20 inverted-T figures to make them appear equal to a horizontal line and rated the confidence in their accuracy after each trial. One group viewed figures of varying sizes, a second group viewed figures of standard size, and a third group viewed figures of standard size but received feedback on their accuracy immediately after completing Trial 5. Except for a significant increase in accuracy on Trial 6 for the Feedback Group, there were no differences in performance among groups. Subjects made the vertical line significantly shorter than the horizontal line on initial trials but their accuracy improved over trials. In contrast, there was no consistent increase in confidence, and several analyses indicated that confidence ratings were unrelated to accuracy. These results suggest that the subjects were unaware of the decrement in illusion that occurred over trials.

Achievement↗

PubMed2000

State anxiety, performance accuracy, and work pace in a simulated pharmacy dispensing task.

This study examined the effects of scores on state anxiety on overall accuracy of performance and speed of working in a simulated pharmacy dispensing task. 75 undergraduates worked in a simulated pharmacy environment, designed by Schell and Grasha in 1998, to fill 42 mock orders for simulated pharmacy items. Participants' accuracy and work pace in the simulation, presimulation stress, and postsimulation perceived workload and state anxiety were measured. Analysis indicated that state anxiety and overall accuracy were strongly related. State anxiety appears to be one of the best predictors of errors in the simulated pharmacy dispensing task found so far, while the lack of relationship between work pace and accuracy was confirmed. Work pace predicted accuracy, indirectly, but only after statistically removing the effects of anxiety, task frustration, significant-other stress, and grade point average.

Anxiety↗

PubMed2002

Recognition accuracy by experienced men and women players of basketball.

This study examined 30 experienced basketball players' recognition accuracy by sex, playing position (guard, forward, and center), and situations in the game of basketball. The study used a perceptual cognitive paradigm in which subjects viewed slides of structured and unstructured game situations and accurately recognized the presence or absence of the basketball. A significant difference in recognition accuracy by sex, players' position, and structure of the game situation was found. Male players' recognition accuracy was better than the female players'. The recognition accuracy of subjects who played guard was better than that of subjects who played forward or center. The players' recognition accuracy was more accurate when observing structured plays versus unstructured plays. The conclusion of this study suggested that experienced basketball players differ in their cognitive and visual searching processes by sex and player position within the sport of basketball.

Adult↗

PubMed2002

Assessment of fine motor skill in musicians and nonmusicians: differences in timing versus sequence accuracy in a bimanual fingering task.

While professional musicians are generally considered to possess better control of finger movements than nonmusicians, relatively few reports have experimentally addressed the nature of this discrepancy in fine motor skills. For example, it is unknown whether musicians perform with greater skill than control subjects in all aspects of different types of fine motor activities. More specifically, it is not known whether musicians perform better than control subjects on a fine motor task that is similar, but not identical, to the playing of their primary instrument. The purpose of this study was to examine the accuracy of finger placement and accuracy of timing in professional musicians and nonmusicians using a simple, rhythmical, bilateral fingering pattern and the technology that allowed separate assessment of these two parameters. Professional musicians (other than pianists) and nonmusicians were given identical, detailed and explicit instructions but not allowed physically to practice the finger pattern. After verbally repeating the correct pattern for the investigator, subjects performed the task on an electric keyboard with both hands simultaneously. Each subject's performance was then converted to a numerical score. While musicians clearly demonstrated better accuracy in timing, no significant difference was found between the groups in their finger placement scores. These findings were not correlated with subjects' age, sex, limb dominance, or primary instrument (for the professional musicians). This study indicates that professional musicians perform better in timing accuracy but not spatial accuracy while executing a simple, novel, bimanual motor sequence.

Adult↗

PubMed2004

Accuracy of blood glucose estimation by children with diabetes: an investigation of repeated practice with growth curve modeling.

This study used growth curve modeling to explore whether practicing the task of estimating blood glucose levels would increase accuracy in children with type 1 diabetes. It was predicted that accuracy would improve with practice and that younger, anxious, poorly adjusted children would improve most. 43 attendees at a diabetes summer camp participated. Their mean age was 13.4 yr. (SD = 1.6). All were Euro-American, and 22 were girls. Change in accuracy was best represented by a quadratic function, and this model fit the data well. Overall, participants' accuracy improved initially and then deteriorated. Results indicate that older children were more likely to improve and then deteriorate. Younger children were more likely to improve and sustain those improvements. Results indicate that practicing the task of estimating is not an effective way to increase accuracy and may be contra-indicated. These results can help guide research and clinical use of glucose estimation in children.

Adaptation, Psychological↗

PubMed1991

Accuracy of ambulatory blood pressure determination: a comparative study.

This study was designed to discriminate, according to their accuracy, between three ambulatory pressurometers (Diasys 200R, Novacor; P IV, Del Mar Avionics; SpaceLab 90202, SpaceLab). The evaluation was performed against invasive arterial reference measurements. Accuracy was assessed by calculating the error on pressure (EOP) as the difference between invasive and non-invasive measurement of arterial blood pressure. For the systolic values, accuracy (mean of EOP differences) and uncertainty (SD of these differences) were -0.9 +/- 9.7, -4.3 +/- 10.1 and -16.7 +/- 10.1 mmHg for, respectively, Diasys, PIV and SpaceLab. For diastolic values, they were, respectively, 5.9 +/- 6.7, 6.8 +/- 8.5 and 9.1 +/- 6.6 mmHg. EOP was then separated in two different types of errors: (i) the error of dispersion appreciated by the index of homogeneity calculated by a Lehmann analysis and leading to a statistical classification (ii) the error due to the drift of EOP with the reference value, this last error being easier to correct. Two different behaviours were observed for the EOP: (i) the drift of EOP of systolic values was significantly larger for the oscillometric (SpaceLab) than for the auscultatory (Diasys and P IV) method, with no difference between Diasys and P IV (ii) the homogeneity index was not statistically different among these three devices. These data suggest that, in case the correction of the drift of EOP is carried out, there is no statistical significant difference in accuracy between these three pressurometers. However, in our experimental conditions, the two ambulatory pressurometers recording the Korotkoff sounds have a better accuracy than the one using the oscillometric approach.

Adult↗

PubMedDate not supplied

Relationships of nurses' critical thinking ability and perceived patient self-disclosure to accuracy in assessment of depression.

This descriptive study examined the relationships of nurses' critical thinking ability and perceived patient self-disclosure to accuracy in nursing assessment of depression in older medical patients. The sample consisted of 120 female nurse-patient dyads. Critical thinking ability was measured by the Watson-Glaser Critical Thinking Appraisal. Accuracy in nursing assessment was measured by deviations between the patient's SDS observed score and the patient's SDS predicted score. The patient's predicted score was based on the relationship between the Depression Status Inventory and Self-Rating Depression Scale. Perceived patient self-disclosure was measured by a 3-point system on patients' disclosure of information on symptoms of depression. A Pearson product-moment correlation and multiple regression analysis were used to analyze the data. The result showed that nurses' education was not significantly related to accuracy in assessment but related to critical thinking ability (r = .26; p = .004). Nurses' critical thinking ability was significantly related to accuracy in nursing assessment depression (r = -.24; p = .008). Perceived patients self-disclosure was not significantly related to accuracy in nursing assessment of depression.

Adult↗

PubMed1981

Precision and accuracy: concepts and assessment by method evaluation testing.

Achieving precision and accuracy in routine clinical analyses is a complex task, requiring the identification, estimation, and elimination of sources of analytical error. This review first considers concepts of precision and accuracy, including discussions of the meaning of measurement process, analytical method, state of statistical control, precision, imprecision, accuracy, inaccuracy, systematic error, overall or total error, true value, traceability, and compatability. These concepts provide the basis upon which the performance of analytical methods can be evaluated. The second part of the review considers how precision and accuracy are assessed by the use of method evaluation experiments. The approach emphasizes the development of an evaluation protocol based on the analytical characteristics which represent the performance of the method. This includes discussions of the familiarization period; testing analytic range and linearity; testing precision by a replication experiment; testing accuracy by recovery, interference, and comparison of methods experiments; the selection of a comparative analytical method; the statistical analysis of method comparison data, including the interpretation of that data; the collaborative testing.

Aspartate Aminotransferases↗