Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Accuracy”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 487 records · Page 27Linked to original sources
PubMed2002

Influence of EUS training and pathology interpretation on accuracy of EUS-guided fine needle aspiration of pancreatic masses.

BACKGROUND: Identification, staging, and fine needle aspiration of pancreatic mass lesions are probably the most technically demanding EUS skills. This study evaluated the effect of formal training on the diagnostic accuracy of EUS-guided fine needle aspiration (EUS-FNA) of pancreatic masses and the source of the variability in diagnostic accuracy between initial and later procedures. METHODS: Sixty-five patients with pancreatic masses underwent EUS-FNA between April 1998 (introduction of EUS-FNA) and August 1999, 20 of whom were examined by 3 endosonographers without prior experience with EUS-FNA. The initial experience of these 3 endosonographers (April to December 1998; group A patients), which included a formal training period of 2 months, and their later experience (January to August 1999; group B patients) were evaluated. Final diagnoses were determined by surgical pathology or clinical follow-up. All EUS-FNA samples were reviewed by 4 blinded pathologists to determine the contribution of pathologist interpretation to varying EUS-FNA accuracy. RESULTS: After a short training period, there was a significant improvement in EUS-FNA accuracy (33% vs. 91%; p = 0.004). After pathology review, good agreement was identified between original FNA interpretation and that on review (kappa = 0.78; 95% CI [0.5, 1.0]). There were differences between the mean cellularity score (2.8 vs. 1.8, p = 0.01) and mean number of passes (5.1 vs. 2.8, not significant) for correct versus incorrect FNA specimens. CONCLUSION: Significant improvements in EUS-FNA accuracy can be achieved with a short period of mentored training. EUS-FNA errors during the initial learning phase are primarily due to inadequate specimens. Interpretation of pancreatic EUS-FNA specimens remained consistent before and after training.

Aged↗
PubMed2000

Accuracy of dobutamine technetium 99m sestamibi SPECT imaging for the diagnosis of single-vessel coronary artery disease: comparison with echocardiography.

BACKGROUND: Recent experimental studies have shown that technetium 99m methoxyisobutyl isonitrile (MIBI) underestimates flow heterogeneity induced by dobutamine and that this might have an impact on the sensitivity of dobutamine MIBI in patients with single-vessel coronary artery disease (CAD). This study compares the accuracy of dobutamine MIBI single-photon emission computed tomography (SPECT) and simultaneous echocardiography in the diagnosis of single-vessel CAD. METHODS AND RESULTS: Ninety-one patients (age 57 +/- 12 years) with single-vessel CAD or without significant CAD were studied with dobutamine (up to 40 microg/kg per minute)-atropine (up to 1 mg) stress echocardiography (DSE) and simultaneous MIBI SPECT imaging. CAD was predicted on the basis of myocardial ischemia (transient wall motion abnormalities by DSE and reversible perfusion defects by MIBI). Ischemia was detected by MIBI in 30 of the 54 patients with and in 10 of the 37 patients without significant single-vessel CAD (sensitivity 56%, confidence interval [CI] 45 to 66; specificity 73%, CI 64 to 82; accuracy 63%, CI 53 to 73). Ischemia was detected by DSE in 30 patients with and in 6 patients without significant CAD (sensitivity of DSE 56%, CI 45 to 66; specificity 84%, CI 76 to 91; accuracy 67%, CI 57 to 77, P = not significant vs MIBI). For both imaging methods, sensitivity was significantly higher in patients with left anterior descending than in patients with left circumflex or right coronary artery stenosis (75% vs 40%, P <.05). The addition of echocardiography to MIBI did not improve the diagnostic accuracy (68% CI 59 to 78, P = not significant vs DSE or MIBI alone). CONCLUSIONS: DSE and MIBI SPECT imaging have similar moderate sensitivity for the diagnosis of single-vessel CAD. Sensitivity of each of these techniques is higher in patients with left anterior descending than in patients with left circumflex or right coronary artery stenosis. There is no improvement of diagnostic accuracy by use of the combination of both techniques.

Aged↗
PubMed2001

Diagnostic accuracy of fine-needle aspiration and frozen section in nodular thyroid disease.

OBJECTIVE: To assess the diagnostic accuracy of fine-needle aspiration (FNA) and frozen section (FS) in nodular thyroid disease. SETTING: Tertiary care academic medical center. STUDY DESIGN: Retrospective review of 139 consecutive patients undergoing surgery for nodular thyroid disease. FNA and FS sensitivity, specificity, and accuracy were calculated with respect to permanent section histology. RESULTS: Among 63 patients with an FNA interpreted as either benign (n = 38) or malignant (n = 25), FNA was accurate (sensitivity 89%, specificity 97%, accuracy 94%). FS identified only one case of carcinoma missed by FNA. Among 76 patients with a "suspicious" FNA, FS was reasonably accurate (sensitivity 67%, specificity 100%, accuracy 89%), but was deferred in 50% of cases. CONCLUSION: Given high FNA accuracy, more selective use of FS is suggested. SIGNIFICANCE: The study results will assist with intra-institutional patient counseling and intraoperative decision-making with respect to FNA and FS results in patients with nodular thyroid disease.

Adenoma↗
PubMed2003

Multiplane transesophageal echocardiography performed according to the guidelines of the American Society of Echocardiography in patients with mitral valve prolapse, flail, and endocarditis: diagnostic accuracy in the identification of mitral regurgitant defects by correlation with surgical findings.

Multiplane transesophageal echocardiography is a useful tool to study mitral regurgitation. We evaluated the diagnostic accuracy of multiplane transesophageal echocardiography performed according to the guidelines of the American Society of Echocardiography. We used 4 midesophageal and 2 transgastric views in 313 patients with degenerative lesions, endocarditic lesions, or both to identify regurgitant defects, comparing transesophageal echocardiography results with surgical findings. The overall diagnostic accuracy using individual scallops was 97.2% (P <.00001) with a sensitivity of 96.6% and a specificity of 97.6%. Considering the single sections of the mitral valve, an accuracy of 98%, 97.1%, and 98%, was found, respectively, for the lateral, middle, and medial third of the anterior leaflet. For the posterior leaflet, the accuracy was 98% for the lateral scallop, 98.4% for the middle, and 96.1% for the medial. This strategy provides good accuracy in diagnosing both simple and challenging mitral-valve lesions and its widespread use should be recommended.

Adult↗
PubMed2002

Limited accuracy and reliability of infrared axillary and aural thermometers in a pediatric outpatient population.

OBJECTIVE: To evaluate the accuracy and reliability of infrared axillary and aural thermometers in the outpatient setting. STUDY DESIGN: A prospective observational study of infrared axillary, aural, and digital rectal temperature values from 198 children, aged 3 to 36 months (mean, 1.3 years). RESULTS: Sensitivity and specificity of the axillary thermometer for rectal fever were 63.5% and 92.6%, respectively (diagnostic accuracy, 83.3%); those for the aural thermometer were 68.3% and 94.8%, respectively (diagnostic accuracy, 86.4%). For all patients, the mean biases of the axillary and aural temperatures were -0.33 degrees F and -0.24 degrees F, respectively. The biases of both thermometers' measurements were significantly correlated with rectal temperature (P <.02); thus, as rectal temperature increased, the accuracy of the compared axillary and aural temperature decreased. Underestimation of rectal temperature was greatest among febrile 1- to 3-year-old children (axillary bias, -1.20; aural bias, -0.36). Age was correlated with an axillary temperature bias (P <.01). CONCLUSION: Axillary and aural infrared thermometers were comparable, albeit significantly different than rectal temperature measurements, particularly as the child's age and rectal temperature increased. These thermometers may be useful as noninvasive screening methods in outpatient settings for children who are at least 3 months old, but rectal values should be used for clinical accuracy.

Child, Preschool↗
PubMed2002

Compositional stability and marginal accuracy of complete cast crowns made with as-received and recast type III gold alloy.

STATEMENT OF PROBLEM: The effect of combining new and recast metal on the compositional stability of the alloy used and accuracy of the final restoration is not known. PURPOSE: This study characterized the elemental compositional stability of as-received and recast type III gold alloy. The effect of combining these alloys on the marginal accuracy of complete cast crowns also was evaluated. MATERIAL AND METHODS: Sixty standardized type III gold alloy complete crowns were made on epoxy resin dies duplicated from a metal master die with conventional laboratory techniques. Three casting protocols (n = 20 each) were established in relation to the proportion of as-received and recast gold alloys: Group A (100% as-received metal), Group B (50% wt new metal, 50% wt once recast metal), and Group C (100% once recast metal). An elemental analysis was performed at 3 sites along the cast crown (cervical, middle, and occlusal) with x-ray energy-dispersive spectroscopy. Marginal accuracy was measured with a microscope before and after cementation. Results were subjected to 1-way analysis of variance followed by the Ryan-Einot-Gabriel-Welsch multiple-range test at a 1% level of significance. RESULTS: Elemental composition was significantly different among the casting groups (P<.001). The mean weight percentage values were 72.4% to 75.7% Au, 4.5% to 7.0% Pd, 10.7% to 11.1% Ag, 7.8% to 8.4% Cu, and 1.0% to 1.4% Zn. Statistically but not clinically significant differences also were found for marginal accuracy. The marginal discrepancy was less than 25 microm for all casting conditions, with the lowest value recorded for Group A (7 microm), the highest for Group C (12 microm), and an intermediate value for Group B (9 microm) specimens. CONCLUSION: Recasting type III gold alloys may adversely affect the marginal accuracy of complete cast crowns. In this study, however, such effects were not clinically significant.

Analysis of Variance↗
PubMed2003

Accuracy of open tray implant impressions: an in vitro comparison of stock versus custom trays.

STATEMENT OF PROBLEM: The accuracy of an implant fixture-level impression is affected by the type of impression tray used. PURPOSE: The purpose of this in vitro study was to investigate the accuracy of open tray implant impressions comparing polycarbonate stock impression trays and rigid custom-made impression trays to make implant fixture-level impressions. MATERIAL AND METHODS: Gold cylinder pairs, splinted by gold bars (reference frameworks) were constructed on an aluminum typodont. Polyether impressions were made of 2 pairs of Brånemark 3.75-mm diameter fixtures mounted in an aluminium typodont, with 3 stock impression trays, 3 close-fit custom trays, and 3 spaced custom impression trays, by use of an open tray technique. The casts produced were assessed for accuracy by attaching the reference frameworks with alternate single screws and measuring the vertical fit discrepancy of these reference frameworks to the analogs within the working cast using a traveling microscope. Comparison of gap dimensions by tray type was performed with a nonparametric Kruskal-Wallis analysis of variance (ANOVA) followed by pair-wise Mann-Whitney U tests. To adjust for multiple comparisons in the post-ANOVA contrasts (P<.02). Comparison of gap dimensions between anterior and posterior regions were performed with Mann-Whitney U tests (P <.05). RESULTS: The results showed that the mean fit accuracy, as measured by vertical fit discrepancy, of casts from the stock trays (23 +/- 20 microm) were statistically significantly less (P<.001) than the spaced custom trays (12 +/- 10 microm) or close fit custom trays (11 +/- 10 microm). The difference in median gap size for analogs with a 20-mm separation was 10 microm. CONCLUSION: Within the limits of this in vitro study, rigid custom trays produced significantly more accurate impressions than the polycarbonate stock trays. The stock trays used in this study could not produce accurate impressions consistently. For analogs with a 20-mm separation, there was a difference in medians of 10 microm in accuracy between the stock and custom trays.

Analysis of Variance↗
PubMed2005

Parts per million mass accuracy on an Orbitrap mass spectrometer via lock mass injection into a C-trap.

Mass accuracy is a key parameter of mass spectrometric performance. TOF instruments can reach low parts per million, and FT-ICR instruments are capable of even greater accuracy provided ion numbers are well controlled. Here we demonstrate sub-ppm mass accuracy on a linear ion trap coupled via a radio frequency-only storage trap (C-trap) to the orbitrap mass spectrometer (LTQ Orbitrap). Prior to acquisition of a spectrum, a background ion originating from ambient air is first transferred to the C-trap. Ions forming the MS or MS(n) spectrum are then added to this species, and all ions are injected into the orbitrap for analysis. Real time recalibration on the "lock mass" by corrections of mass shift removes mass error associated with calibration of the mass scale. The remaining mass error is mainly due to imperfect peaks caused by weak signals and is addressed by averaging the mass measurement over the LC peak, weighted by signal intensity. For peptide database searches in proteomics, we introduce a variable mass tolerance and achieve average absolute mass deviations of 0.48 ppm (standard deviation 0.38 ppm) and maximal deviations of less than 2 ppm. For tandem mass spectra we demonstrate similarly high mass accuracy and discuss its impact on database searching. High and routine mass accuracy in a compact instrument will dramatically improve certainty of peptide and small molecule identification.

Freeze Drying↗
PubMed2002

Facial identity and facial emotions: speed, accuracy, and processing strategies in children and adults.

As yet, nearly all studies in face and facial affect recognition typically provide only data on the accuracy of processing, invariably also in the absence of reference data on abstract information processing. In this study, accuracy and speed of abstract visuo-spatial processing, face recognition, and facial emotion recognition were investigated in normal school children (7-10 years) and adults (25+/-4 years). In the age range of 7-10 years, accuracy of facial processing hardly increased, while speed did substantially increase with age. Adults, however, were substantially more accurate and faster than children. Differences between facial and abstract information processing were related to type of processing strategy, that is, configural or holistic processing versus featural or piecemeal processing. Improvement in task performance with age is discussed in terms of an enhanced efficiency of the configural organization of facial knowledge (facial information processing tasks), together with a further increase in processing capacity (all tasks). The differential developmental course of speed and accuracy levels indicates that speed is a more sensitive measure when children get older. Moreover, it also suggests that speed of performance, in addition to accuracy, might be successfully used in the assessment of clinical deficits, as has recently been demonstrated in children with autistic disorders of social contact.

Adult↗
PubMed2003

Are classification accuracy statistics underused in neuropsychological research?

The prevalence of classification accuracy statistics was calculated in five prominent neuropsychology journals and five leading neurology journals for the years 2000 and 2001. Only 29% of neuropsychological articles judged to be appropriate for classification accuracy statistics presented sufficient data to calculate a full range of such analyses. Moreover, classification accuracy statistics were significantly less prevalent in neuropsychology journal articles than in studies published in neurology journals during the same time period. Various indices of sensitivity and/or specificity were present in 31% of neuropsychology articles, whereas fewer than 3% reported predictive values or risk ratios. These findings indicate that classification accuracy statistics, most notably predictive values and risk ratios, are potentially underused in neuropsychology. Investigators and research consumers are encouraged to consider the applicability of classification accuracy statistics as a means of evaluating the clinical relevance of neuropsychological research findings.

Bibliometrics↗
PubMed2006

Accuracy of food intake reporting in obese subjects with metabolic risk factors.

The aim of the present study was to determine the accuracy of reported energy intake according to a food-frequency questionnaire (FFQ) and dietary records (DR) in obese subjects with metabolic syndrome risk factors. Subjects were twenty-three men and twenty-seven women with mean BMI of 35.7 (range 30.5-43.8) kg/m(2) who participated in a dietary interview based on a FFQ and completed weighed DR. Total energy expenditure was measured with the doubly labelled water method. Total energy expenditure, measured RMR and physical activity level did not differ between under-reporters (50 % of the sample) and non-under-reporters. Under-reporters had lower median intake of sweets, desserts and snacks than non-under-reporters (100 v. 161 g/d (P = 0.0008) and 61 v. 128 g/d (P = 0.0002) according to the FFQ and DR, respectively). The DR also showed lower energy density (6.7 (sd 1.3) v. 7.9 (SD 1.6) kJ/g; P = 0.0064), lower intake of sugary drinks (0 v. 167 g/d; P = 0.0063) and higher scores for dietary restraint (9.0 (sd 5.0) v. 6.1 (SD 3.5); P = 0.0285) in under-reporters. Energy density was associated with accuracy according to the FFQ (Spearman's rank correlation coefficient (RS) 0.406; P = 0.0034) and the DR (RS 0.537; P < 0.0001). In multivariate analysis, consumption of bread and sweets, desserts and snacks measured by the FFQ was positively associated with accuracy (R(2)adjusted 0.46 (95 % CI 0.32, 0.70)). According to the DR, consumption of sweets, desserts and snacks was also associated with accuracy, as was dietary restraint (inversely) (R(2)adjusted 0.67 (95 % CI 0.54, 0.83)). In obese subjects with metabolic risk factors, intake of sweets, desserts and snacks, bread and dietary restraint were determinants of reporting accuracy.

Adult↗
PubMed2006

Accuracy of estimates of food portion size using food photographs--the importance of using age-appropriate tools.

BACKGROUND: In order to obtain a measure of nutrient intake, a measure or estimate of the amount of food consumed is required. Weighing foods imposes a large burden on subjects, often resulting in underreporting. Tools are available to assist subjects in providing an estimate of portion size and these include food photographs. The application of these tools in improving portion size estimation by children has not been investigated systematically. OBJECTIVES: To assess the accuracy with which children are able to estimate food portion sizes using food photographs designed for use with adults, and to determine whether the accuracy of estimates is improved when age-appropriate portion size photographs are provided. DESIGN: Original data from three separate studies, on the accuracy of portion size estimates by adults using food photographs, by children using adult photographs and by children using age-appropriate photographs, are analysed and compared. SUBJECTS: One hundred and thirty-five adults aged 18 to 90 years and 210 children aged 4 to 11 years. RESULTS: Children's estimates of portion sizes using age-appropriate food photographs were significantly more accurate (an underestimate of 1% on average) than estimates using photographs designed for use with adults (an overestimate of 45% on average). Accuracy of children's estimates of portion size using age-appropriate photographs was not significantly different from that of adults. Children overestimated a food's weight by 18% on average and adults underestimated by 5%. CONCLUSIONS: Providing children with food photographs depicting age-appropriate portion sizes greatly increases the accuracy of portion size estimates compared with estimates using photographs designed for use with adults.

Adolescent↗
PubMed2002

Accuracy and precision of two in-shoe pressure measurement systems.

The recent rapid adoption of insole pressure measurement systems for clinical and ergonomic evaluations of human gait has necessitated a comprehensive understanding of the accuracy and precision of such systems. Five bench experiments were performed to examine the Pedar and F-Scan in-shoe pressure measurement systems. The insoles examined were the Pedar Y-sized right insole and the F-scan insole trimmed to the size and shape of a Pedar Y-sized insole. Data were sampled at 50 Hz at different levels of applied pressure, calibration procedure, duration of pressure application, insole age of use and experiment day or week. The system accuracy was determined by the per cent error of measurement, the system precision by the 95% tolerance interval of the per cent error. The results show that system accuracy and precision varied among levels of applied pressure, calibration procedure, duration of pressure application and insole age of use. The Pedar system showed the greatest accuracy and precision when the insole was new and measurements were taken (1) after a system calibration as specified by the manufacturer, (2) in the 50 - 500 kPa pressure range and (3) within a few seconds after pressure was applied. Under this condition, the measurement error was in the range -0.6 to 2.7%, and the magnitude (upper bound minus lower bound) of the 95% tolerance intervals was from 13.5 to 18.7%. Measuring less than 35 kPa with the Pedar system is not recommended. To ensure the accuracy and precision of the F-Scan system, users are recommended to estimate the range of the applied pressure and then choose a similar pressure level for calibration. Under this condition, the measurement error was in the range 1.3 - 5.8% and the magnitude (upper bound minus lower bound) of the 95% tolerance intervals was estimated to be in the range 1.1 - 14.8%. When the calibration pressure was outside this range of applied pressure, the per cent errors were considerably higher, ranging from -26.3 to 33.9%.

Calibration↗
PubMed2004

Determinants of sexual arousal and accuracy of its self-estimation in sexually functional males.

Men with and without sexual dysfunction present with varying patterns of agreement between subjective estimates of sexual arousal and more objective psychophysiological measures of the same construct. This relative accuracy seems to be associated with sexual function, with men who have sexual dysfunction presenting less accurate estimations (mostly reporting below measured arousal levels). The purpose of this study is to clarify the processes underlying sexual arousal and the accuracy of its self-estimation. We looked at potential predictors of sexual arousal (subjective and physiological) and accuracy in estimating objective sexual arousal in a sample of 60 sexually functional males. Predictors included pre-existing sexual attitudes (erotophobia), both trait and state positive and negative affect, self-focused attention, and interoceptive awareness. Results indicate that this sexually functional sample generally reported below their own erection level. Interestingly, trait negative affect was associated with somewhat lower levels of subjective arousal and higher levels of physiological arousal. On the other hand, state positive affect facilitated both subjective and objective arousal and increased somewhat the accuracy of estimates of erectile responding. Pre-existing sexual attitudes as well as variations in self-focused attention and interoceptive awareness evidenced little effect on sexual arousal or the accuracy of its estimation.

Adult↗
PubMed1989

Changes in limb striking pattern: effects of speed and accuracy.

This study investigated the changes in an arm striking pattern as a result of practice and the effects of speed and accuracy requirements on such changes. The task was to strike a baseball-size foam ball from a batting tee adjusted to the height of each subject's iliac crest. Ten righthanded subjects, initially displaying an inefficient striking pattern, volunteered for this study. All subjects performed the task according to the following conditions: (1) speed, (2) accuracy, and (3) speed and accuracy. Each subject completed 10 trials in each condition (randomly ordered) for five consecutive days. A high-speed camera (64 fps) was used to photograph subjects' striking patterns for each condition over the 5-day period. Analysis of variance of joint angles at arm reversal and contact and velocity of hand relative to the glenohumeral axis at contact revealed that subjects initially constrained limb segments to act in a unitary fashion; then, with practice, a more efficient pattern was developed. The requirement of speed was found to enhance a change in limb configuration, whereas the requirement of accuracy, and subsequent reduction in speed, impeded the development of a more efficient striking pattern. Analysis of radial error revealed no differences in accuracies to the target by either condition or day of practice. A graphic analysis of segmental angular momentum versus relative time showed that joint angle changes allowed subjects to transfer angular momentum and thereby increase the velocity of the hand at contact.

Acceleration↗
PubMedDate not supplied

Accuracy of body mass index in detecting an elevated alanine aminotransferase level in adolescents.

AIM: We evaluated the accuracy of body mass index (BMI) in detecting an elevated alanine aminotransferase (ALT) level in adolescents, taking into account the effects of gender, age, ethanol intake, hepatitis B virus (HBV) and hepatitis C virus (HCV) infections, and drug consumption. SUBJECTS: A representative sample of 454 adolescents (11-17 years) from two cities in northern Italy was studied (the Dionysos Study). METHODS: z-BMI was calculated as the z-score of BMI using national growth charts. Logistic regression was used to quantify the contribution of the variables of interest to an elevated ALT (> 30 UL(-1)). Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated, and areas under receiver-operator characteristic curves (AUC) were used to evaluate accuracy. RESULTS: An elevated ALT was detected in 21 adolescents (4.6%). Among the studied variables, only male gender (OR=6.7, 95% CI 2.0-23.2) and z-BMI (OR=2.1, 95% CI 1.4-3.2) were significant predictors of elevated ALT. The accuracy of the prediction was 0.69 (95% CI 0.59-0.79) for gender and 0.71 (95% CI 0.59-0.81) for z-BMI. By combining gender and z-BMI, the accuracy rose to 0.80 (95% CI 0.71-0.89). CONCLUSION: BMI is a good predictor of elevated ALT in Italian adolescents and gender adds to the accuracy of the prediction.

Adolescent↗
PubMedDate not supplied

Respiratory inductive plethysmography accuracy at varying PEEP levels and degrees of acute lung injury.

BACKGROUND AND OBJECTIVE: This study was performed to assess the accuracy of respiratory inductive plethysmographic (RIP) estimated lung volume changes at varying positive end-expiratory pressures (PEEP) during different degrees of acute respiratory failure. METHODS: Measurements of inspiratory tidal volume were validated in eight piglets during constant volume ventilation at incremental and decremental PEEP levels and with increasing severity of pulmonary injury. RIP accuracy was assessed with calibration from the healthy state, from the disease state as the measurement error was assessed, and at various PEEP levels. RESULTS: Best results (bias 3%, precision 7%) were obtained in healthy animals. RIP accuracy decreased with progressing degrees of acute respiratory failure and was PEEP dependent, unless RIP was calibrated again. When calibration was performed in the disease state as the measurement error was assessed, bias was reduced but precision did not improve (bias -2%, precision 9%). CONCLUSIONS: RIP accuracy is within the accuracy range found in monitoring devices currently in clinical use. Most reliable results with RIP are obtained when measurements are preceded by calibration in pulmonary conditions that are comparable to the measurement period. When RIP calibration is not possible, fixed weighting of the RIP signals with species and subject size adequate factors is an alternative. Measurement errors should be taken into account with interpretation of small volume changes.

Acute Disease↗
PubMed2002

Evaluation of gene-finding algorithms by a content-balancing accuracy index.

A content-balancing accuracy index, called q(9), to evaluate gene-finding algorithms has been proposed. Here the concept of content-balancing means that the evaluation by this index is independent of the coding and non-coding composition of the sequence being evaluated. Since the coding and non-coding compositions are severely unbalanced in eukaryotic genomes, the performance of gene-finding algorithms is either over- or under-evaluated by the widely used accuracy indices, e.g., the correlation coefficient, due to the lack of content-balancing ability. Using the new accuracy index q(9), seven gene-finding algorithms, FGENES; Gene-Mark.hmm; Genie; Genescan; HMMgene; Morgan and MZEF, were compared and evaluated. It is shown that Genescan is still the best one, but with q(9)= 89%, averaged over the prediction for 195 sequences. In addition to the content-balancing ability, q(9) has the merit of having definition in all possible cases. It is also shown that the traditional specificity s(p) carries important information on the performance of the algorithm being evaluated. The set of sensitivity s(n), specificity s(p) and the accuracy q(9) constitutes a complete kit to evaluate gene-finding algorithms at nucleotide level. In addition, a graphic method to compare and evaluate gene-finding algorithms has been proposed, too. Its major advantage is that the overall performance of algorithms can be grasped quickly in a perceivable form. Additionally, the new accuracy index q(9) may be applied to evaluate the performance of weather forecast, clinical diagnosis, psychological examination and protein secondary structure prediction etc.

Algorithms↗