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Results for “Reproducibility”

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PubMed2002

Intercenter reproducibility of binary typing for Staphylococcus aureus.

The reproducibility of the binary typing (BT) protocol developed for epidemiological typing of Staphylococcus aureus was analyzed in a biphasic multicenter study. In a Dutch multicenter pilot study, 10 genetically unique isolates of methicillin-resistant S. aureus (MRSA) were characterized by the BT assay as presented by van Leeuwen et al. [J. Clin. Microbiol. 2001 39 (1) 328]. The BT assay, including a standardized DNA extraction protocol was performed in duplicate in eleven medical microbiology laboratories. Two different hybridization detection procedures were applied and a prelabeled DNA sample as process control was included. Only three laboratories accurately identified all strains. Divergence in technical procedures resulted in misinterpretation due to an increasing number of faint or absent hybridization signals in combination with high background staining. The binary type of the process control was determined correctly by all participating laboratories. The feasibility of the BT protocol was related directly to the skill of the laboratory personnel. On the basis of the national study, we concluded that the DNA extraction protocol needed modification to improve DNA yield and purity. Subsequently, seven European laboratories participated in an international study to determine the reproducibility of the modified BT protocol. Each center was asked to analyze 10 DNA samples previously extracted from 10 MRSA strains (phase 1) and, additionally, to analyze 10 MRSA strains, using the standardized or their in-house DNA isolation protocol (phase 2). A prelabeled DNA process control sample was included again. The binary types of all DNA samples were identified correctly by all but one laboratories. This latter laboratory diverged from the protocol by adding an excess of labeled DNA to the hybridization mixture, resulting in a high background and, therefore, noninterpretable BT results. All centers produced identical BT results for the process control. Five of the seven centers correctly identified the binary types of all 10 MRSA strains in phase 2 of the international study. Three of these centers used their in-house DNA extraction protocol. Divergence from the standard BT protocol in the remaining two centers resulted in no interpretable BT data for the 10 MRSA strains. The study demonstrated that each center that followed the BT protocol to the letter could generate reproducible results, irrespective whether or not an in-house DNA isolation protocol was used. The current BT protocol thus represents a simple method generating robust, reproducible genotype data for S. aureus strains.

Bacterial Typing Techniques↗

PubMed2002

[Total knee arthroplasty: reproducibility of gait speed].

OBJECTIVE: To calculate the inter-session (test-retest) and inter-observers' reproducibility of the maximal gait speed measured in patients recently operated for osteoarthritis with a total knee arthroplasty. METHODS: Evaluation of the maximal gait speed in 20 patients [t72 +/- 6.5 years] on a 10-meter track by two observers using a manual stopwatch and by an automatic photoelectric stopwatch. The maximal gait speed was measured from three trials in two conditions, with and without crutches, with 1 day of interval at the third and the fourth post-surgery week. RESULTS: The inter-session reproducibility (1-day test-retest) is 0.91 [intraclass correlation coefficient] with crutches and 0.9 without crutches at the third post-surgery week, and 0.96 and 0.94 at the fourth post-surgery week with and without crutches respectively. The inter-observers' reproducibility is 0.9 to 0.99. CONCLUSION: When a standardized protocol is used, the reproducibility of maximal gait speed measurements is excellent. These tests evaluate easily and objectively the maximal gait speed in patients recently operated with a total knee arthroplasty.

Aged↗

PubMed1989

Reproducibility of patch test results: comparison of TRUE Test and Finn Chamber test results.

To evaluate the reproducibility of patch test results, duplicate patch test series comprising 12 allergens were simultaneously applied to either side of the back in 63 patients by the use of a newly developed patch test system, TRUE Test. When a positive test result occurred on only one side of the back, it was regarded as nonreproducible. For evaluation of the concordance of test reactions between the TRUE Test and the Finn Chamber test, the same 12 allergens mixed in petrolatum were also applied to the upper back according to the Finn Chamber technique. The reproducibility of TRUE Test results was compared with the reproducibility of the Finn Chamber test in 76 other patients. The concordance of positive reactions between the two tests was 57%, somewhat lower than in recently published studies. The percentage of nonreproducible positive results was more than twice as high with Finn Chambers, (22 of 58 positive reactions, or 37.9%) as with the TRUE Test (5 of 28 reactions, or 17.9%). However, this difference in reproducibility in the two test systems was not significant as determined by the chi 2 test (p less than 0.05).

Allergens↗

PubMed1999

Digital image analysis: improving accuracy and reproducibility of radiographic measurement.

OBJECTIVE: To assess the accuracy and reproducibility of a digital image analyser and the human eye, in measuring radiographic dimensions. DESIGN: We experimentally compared radiographic measurement using either an image analyser system or the human eye with digital caliper. BACKGROUND: The assessment of total hip arthroplasty wear from radiographs relies on both the accuracy of radiographic images and the accuracy of radiographic measurement. METHODS: Radiographs were taken of a slip gauge (30+/-0.00036 mm) and slip gauge with a femoral stem. The projected dimensions of the radiographic images were calculated by trigonometry. The radiographic dimensions were then measured by blinded observers using both techniques. RESULTS: For a single radiograph, the human eye was accurate to 0.26 mm and reproducible to +/-0.1 mm. In comparison the digital image analyser system was accurate to 0.01 mm with a reproducibility of +/-0.08 mm. In an arthroplasty model, where the dimensions of an object were corrected for magnification by the known dimensions of a femoral head, the human eye was accurate to 0.19 mm, whereas the image analyser system was accurate to 0.04 mm. CONCLUSIONS: The digital image analysis system is up to 20 times more accurate than the human eye, and in an arthroplasty model the accuracy of measurement increases four-fold. We believe such image analysis may allow more accurate and reproducible measurement of wear from standard follow-up radiographs.

Hip Prosthesis↗

PubMed1997

Reproducibility and validity of quality of life measurements in hypertensive patients on stable medication.

OBJECTIVE: The reproducibility and validity of a hypertension-specific questionnaire and a genetic health questionnaire (the MOS Short-form General Health Survey) were evaluated for measuring the quality of life in a randomized controlled trial comparing balloon angioplasty and long-term medication in patients with renovascular hypertension. METHODS: The health questionnaires were filled out by 97 patients with hypertension on stable medication. The reproducibility of the questionnaires was assessed by intraclass correlation coefficients (ICCs). Pearson's correlation coefficients were calculated between the scales of the questionnaires to evaluate the validity. RESULTS: Medication had been changed to eliminate side-effects in an earlier phase of treatment. Only 7% of the patients reported non-compliance with the medication regime. Most patients suffered from physical symptoms, but the impact of long-term antihypertensive medication on the quality of life was not substantial. The reproducibility was good for most scales (ICC > 0.70), except for the role and social functioning scales. All correlations between the scales of the questionnaires were statistically significant and no contradictory correlations were found. CONCLUSIONS: The health questionnaires together form a reproducible and valid instrument for measuring the quality of life of hypertensive patients on stable medication.

Angioplasty, Balloon↗

PubMed2003

Preparation of Ehrlichia ruminantium challenge material for quantifiable and reproducible challenge in mice and sheep.

The causative agent of heartwater, Ehrlichia ruminantium, is a tick-transmitted pathogen that infects bovine endothelial cells. Due to the obligate intracellular nature of this organism obtaining pure material in sufficient quantities for challenge studies is difficult. A murine model is frequently used to study potential vaccine candidates but giving reproducible challenges in this model for heartwater has always been problematic. We have therefore performed a series of experiments to optimize the parameters governing the reproducibility of challenge material. Two cryoprotectants were compared for the preparation of challenge material, buffered lactose peptone (BLP) and sucrose-potassium-glutamate (SPG). In addition two sources of virulent E. ruminantium were used, infected bovine endothelial cultures and infected mouse spleen homogenates. We also examined practical parameters affecting the reproducibility of challenge experiments: the time it takes to deliver the challenge material, the length of time a mouse remains immune to E. ruminantium challenge, and the effect of a given challenge dose. Finally, we performed a pilot study to determine whether mice could be used to titrate challenge material to be used for experiments in sheep. We found that: (a) E. ruminantium-infected mouse spleen homogenate provides more reproducible challenges than tissue culture material; (b) SPG is a better cryoprotectant than BLP; (c) challenge material should be used within 20min of thawing; (d) it is not essential to use syngeneic material for murine challenge experiments; (e) Balb/c mice are more sensitive to E. ruminantium challenge than C57BL/6J mice; (f) mice immunized by infection and treatment for use as positive immune controls should be challenged within 3 months of immunization; and (g) mice should be challenged with a dose not exceeding 10 LD(50)s.

Animals↗

PubMed1993

Reproducibility of subjective immunohistochemical estrogen- and progesterone receptor determination in human endometrium.

To obtain a reliable scoring system for semi-quantitation of estrogen- (ER) and progesterone receptors (PgR) in human endometrial tissue, we investigated the reproducibility of subjective immunohistochemical ER and PgR determination. Specimens of frozen endometrial tissue were stained once (n = 129) or twice (n = 22) using the ER-ICA and PgR-ICA kits from Abbott. The semi-quantitative approach we used included subjective estimates of the overall staining intensity (I) and of the fraction of stained cells (%). Scoring was performed twice by the same observer and once by another observer (n = 87). Intra- and inter-observer agreement were evaluated using Kappa statistics. We found that more comprehensive scorings of I and % could not be agreed upon by the observers. Only simplified estimates of the fraction of cells stained and overall staining intensity were reproducible. Subjective estimates obtained by this method agreed with estimates obtained by counting (n = 38). Simplified H-scores, which were obtained by multiplication of the simplified estimates of % and I, were reproducible, too. In addition, semi-quantitation of ER and PgR by immunohistology was significantly correlated to quantitation by enzyme-immunoassay (n = 39). Thus, it was possible to reproducibly semi-quantitate ER and PgR only by employing a very simple immunohistochemical scoring of ER and PgR.

Endometrium↗

PubMed2001

Three-dimensional accuracy and interfractional reproducibility of patient fixation and positioning using a stereotactic head mask system.

PURPOSE: Conformal radiotherapy in the head and neck region requires precise and reproducible patient setup. The definition of safety margins around the clinical target volume has to take into account uncertainties of fixation and positioning. Data are presented to quantify the involved uncertainties for the system used. METHODS AND MATERIALS: Interfractional reproducibility of fixation and positioning of a target point in the brain was evaluated by biplanar films. 118 film pairs obtained at 52 fractions in 4 patients were analyzed. The setup was verified at the actual treatment table position by diagnostic X-ray units aligned to the isocenter and by a stereotactic X-ray localization technique. The stereotactic coordinates of the treated isocenter, of fiducials on the mask, and of implanted internal markers within the patient were measured to determine systematic and random errors. The data are corrected for uncertainty of the localization method. RESULTS: Displacements in target point positioning were 0.35 +/- 0.41 mm, 1.22 +/- 0.25 mm, and -0.74 +/- 0.32 mm in the x, y, and z direction, respectively. The reproducibility of the fixation of the patient's head within the mask was 0.48 mm (x), 0.67 mm (y), and 0.72 mm (z). Rotational uncertainties around an axis parallel to the x, y, and z axis were 0.72 degrees, 0.43 degrees, and 0.70 degrees, respectively. A simulation, based on the acquired data, yields a typical radial overall uncertainty for positioning and fixation of 1.80 +/- 0.60 mm. CONCLUSIONS: The applied setup technique showed to be highly reproducible. The data suggest that for the applied technique, a safety margin between clinical and planning target volume of 1-2 mm along one axis is sufficient for a target at the base of skull.

Algorithms↗

PubMed1998

Junctioning of lateral and anterior fields in head and neck cancer: a dosimetric assessment of the monoisocentric technique (including reproducibility).

PURPOSE: The matching or junctioning of two lateral fields with an anterior field is commonly performed in the treatment of head and neck cancer. A monoisocentric technique utilising asymmetric collimation is potentially associated with improved dosimetry in the plane of the junction due to decreased reliance on operator skill and the avoidance of couch movement. The aim of this study was not only to assess the average dose delivered in the plane of the junction, but also the reproducibility of this dose for the monoisocentric technique and two other commonly used techniques. METHODS AND MATERIALS: An anthropomorphic head and neck wax phantom was fashioned to allow the placement of 22 TLD chips in a 2-mm thick transverse plane positioned superior to the potential site of the larynx. Three different treatment techniques were used with the phantom being treated by four different operators a minimum of 20 times for each technique: (1) "straight fields"--using isocentric laterals with an anterior field junctioned in the midline. This technique makes no allowance for divergence; (2) "angled fields"--couch and gantry rotation are used to account for divergence; (3) "monoisocentric"--using asymmetric collimators to create a single isocenter. RESULTS: For an applied dose of 1 Gy the monoisocentric technique produced a mean dose measured of 1.01 Gy compared with 1.23 and 0.92 Gy for techniques 1 and 2. The reproducibility of the mean dose measured was better for the monoisocentric technique by a factor of 2. The superior reproducibility of the monoisocentric technique was not found to be operator dependent. CONCLUSIONS: A monoisocentric technique for the treatment of two laterals and an anterior field in head and neck cancer is likely to be associated with more accurate and reproducible dosimetry in the plane of the junction. Our center has subsequently adopted this technique for matching such fields.

Head and Neck Neoplasms↗

PubMed1998

Spatial reproducibility of the ring and tandem high-dose rate cervix applicator.

PURPOSE: High-dose rate (HDR) applicators for uterine cervix brachytherapy are used with increasing frequency. Because multiple HDR fractions are required for treatment, the applicator position reproducibility is of most importance. To study this effect, the clinical data from patients with uterine cervix cancer were examined retrospectively to evaluate the interfraction geometric variation of the HDR applicator and its potential treatment impact. METHODS AND MATERIALS: Eighteen patients with invasive cervical cancer who were treated with definitive radiotherapy at William Beaumont Hospital were included in the study. Patients were treated with 45-50.4 Gy megavoltage external beam to the pelvis, and 35 Gy to the prescription point A from 7 fractions of HDR brachytherapy. The 3-dimensional (3D) interfraction geometrical variation of the ring and tandem (R & T) applicator was measured using predefined reference points in the 7 sets of orthogonal simulation films obtained prior to each HDR application. Spatial reproducibility of the R & T insertion and time-trend of the R & T position variation related to patient's anatomy during the treatment course were analyzed with respect to different groups of patients who had either early or advanced disease. RESULTS: The translational variation of the applicator position for all patients was 6.5, 5.9, and 7.7 mm (one standard deviation), respectively, in the patient's superior-to-inferior (SI), right-to-left lateral (RL), and anterior-to-posterior (AP) direction. The rotational variation was 3.4, 4.6, and 6.0 degrees (one standard deviation) in the patient's coronal, transverse, and sagittal planes. When the patients were grouped based on early disease or advanced disease, the latter demonstrated substantially larger variation (factor of 2) in the applicator position than the former. Furthermore, the time-trend of position variation was observable for both groups of patients. The variations occurred primarily during the first 3 fractions. CONCLUSIONS: Based on the good spatial reproducibility observed in our study, the current clinical procedure for the HDR R & T applicator placement is reliable. Positional reproducibility of the R & T applicator is highly dependent upon the size of tumor volume, which, in turn, deviates the applicator during the early course of HDR brachytherapy. Attention to the construction of the midline block is of paramount importance.

Brachytherapy↗

PubMed2002

Enhancement characteristics of the microbubble agent Levovist: reproducibility and interaction with aspirin.

We investigated the reproducibility of Doppler enhancement indices following intravenous bolus injections of Levovist (Schering AG, Berlin) microbubbles. We also aimed to determine whether observations from animal studies suggesting that aspirin potentiates microbubble enhancement were reproducible in humans. In five healthy volunteers, time enhancement profiles of Doppler intensity following repeated bolus injections of Levovist were acquired from the common carotid artery, hepatic vein and kidney using spectral and power Doppler before and after oral aspirin (600 mg). Peak enhancement (PE), area under the curve (AUC) and decay slopes (lambda) were calculated. Hepatic vein contrast arrival time (AT) was determined subjectively. Well-defined carotid enhancement was seen in 19/20 injections. Reproducibility was high (r > 0.8). PE and AUG were unaffected by aspirin, but lambda was slightly reduced (P = 0.02). Renal power Doppler profiles were well defined (10/10) with no significant changes of AUC, PE or lambda after aspirin. Our study demonstrates good reproducibility of carotid spectral Doppler time intensitometry with Levovist in man. Aspirin does not have a significant effect on enhancement indices except carotid spectral Doppler decay. We conclude that aspirin is unlikely to potentiate microbubble enhancement, as seen in animal studies.

Adult↗

PubMed2001

Contrast echocardiography improves the accuracy and reproducibility of left ventricular remodeling measurements: a prospective, randomly assigned, blinded study.

OBJECTIVES: We sought to assess the impact of contrast injection and harmonic imaging, on the measure by echocardiography of left ventricular (LV) remodeling. BACKGROUND: Left ventricular remodeling is a precursor of LV dysfunction, but the impact of contrast injection and harmonic imaging on the accuracy or reproducibility of echocardiography is unclear. METHODS: We prospectively collected LV images by using simultaneous methods. Then, LV volumes were measured off-line, in blinded manner and in random order. The accuracy of echocardiography was determined in comparison to electron beam computed tomography (EBCT) in 26 patients. The reproducibility of echocardiography was assessed by three blinded observers with different training levels in 32 patients. RESULTS: End-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV) and ejection fraction (EF), as measured by EBCT (195 +/- 55, 58 +/- 24 and 137 +/- 35 ml and 71 +/- 5%, respectively) and echocardiography with harmonic imaging and contrast injection (194 +/- 51, 55 +/- 20 and 140 +/- 35 ml and 72 +/- 4%, respectively), showed no differences (all p > 0.15) and excellent correlations (all r > 0.87). In contrast, echocardiography using harmonic imaging without contrast injection underestimated the EBCT results (all p < 0.01). Reproducibility was superior with rather than without contrast injection for intraobserver and interobserver variabilities (all p < 0.001). Values measured by different observers were different without contrast injection, but were similar with contrast injection (all p > 0.18). Consequently, intrinsic patient differences represented a larger and almost exclusive proportion of global variability with contrast injection for EDV (94 vs. 79%), ESV (93 vs. 82%), SV (87 vs. 53%) and EF (84 vs. 41%), as compared with harmonic imaging without contrast injection (all p < 0.005). CONCLUSIONS: For assessment of LV remodeling, echocardiography with harmonic imaging and contrast injection improved the accuracy and reproducibility, as compared with imaging without contrast injection. With contrast injection, variability was almost exclusively due to intrinsic patient differences. Therefore, when evaluation of LV remodeling is deemed important, assessment after contrast injection should be the preferred echocardiographic approach.

Aged↗

PubMed1996

Poor reproducibility in radiographic grading of femoral cementing technique in total hip arthroplasty.

The first study of the reproducibility of a widely accepted grading system for femoral cementation in total hip arthroplasty is reported. Sixty postoperative radiographs were graded on two occasions at least 2 weeks apart by two experienced observers. The test-retest reproducibility rate was 60% for observer 1 and 70% for observer 2. The interobserver reproducibility varied between 60 and 63% for the different assessments. Between 5 and 6% of cases differed by more than one grade between tests. Kappa statistical analysis confirmed that reproducibility was poor in all cases. This cement grading system, even in the hands of experienced observers, has too high a rate of intraobserver and interobserver error to recommend its use.

Bone Cements↗

PubMed1992

Comparison of the accuracy and reproducibility of the keratometer and the EyeSys Corneal Analysis System Model I.

The EyeSys Corneal Analysis System Model I measures corneal topography using digital image analysis of placido rings reflected off the cornea. With three observers, we compared the accuracy and reproducibility (precision) of the Marco Keratometer Model 1 and EyeSys Corneal Analysis System Model I using four poly(methyl methacrylate) spheres (37.50, 42.51, 47.54, and 55.06 diopters [D]), three steel spheres (40.50, 42.50, and 44.75 D), and 20 normal human eyes (41.50 to 46.00 D). For the spheres, the standard deviations of intra-observer and overall reproducibility for both devices were less than 0.12 D; the absolute mean differences between the measurements of the seven spheres and the known values were 0.25 D or more for two spheres as measured by the keratometer and none as measured by the EyeSys. For the normal corneas, the standard deviations of intra-observer and overall reproducibility for dioptric measurements were 0.07 D and 0.14 D for the keratometer and 0.13 D and 0.19 D for the EyeSys. The EyeSys Corneal Analysis System Model I exceeds keratometer accuracy in reading calibrated spheres and approaches keratometer reproducibility in measuring the 3-mm zone of normal human corneas.

Cornea↗

PubMed1998

Reproducibility of posterior capsule opacification measurement using Scheimpflug videophotography.

PURPOSE: To examine the intraobserver and interobserver reproducibility in measuring posterior capsule opacification (PCO) using a Scheimpflug videophotography system. SETTING: Hayashi Eye Hospital, Fukuoka, Japan. METHOD: Twenty eyes with PCO and 10 without PCO had 5 independent measurements 15 minutes apart performed by 3 observers. The eyes without PCO were selected within 1 week after surgery. Intraobserver and interobserver reproducibility were evaluated using the coefficient of variation and intraclass correlation coefficient. RESULTS: The median coefficients of variation of the 3 observers were 11.6%, 11.3%, and 9.8%, respectively, which indicates an acceptably low observer variability. The intraobserver correlation coefficients of the 3 observers were all more than 0.95, and the interobserver correlation coefficient was 0.976, which indicates excellent reproducibility. CONCLUSION: The results of intraobserver and interobserver reproducibility of PCO measurement using the Scheimpflug videophotography system indicate it would be effective for use in research and clinical management of PCO.

Adult↗

PubMedDate not supplied

Validity and reproducibility of color enhancement of B-mode ultrasound images of far wall thickness of the common carotid artery.

Ultrasound measurement of wall thickness of the carotid artery is used in large cardiovascular clinical trials and epidemiologic studies. Improvements in measurement reproducibility could have important implications for study design and sample size calculations. This study examined the effects of B-mode color on the validity and reproducibility of measurements of far wall thickness of the common carotid artery. Six color maps were compared with normal and inverted gray scales. The validity of B-mode color was assessed by comparing histologic measurements from 20 excised human common carotid arteries with measurements made using each map. No differences were noted in the average far wall thickness measured by any method (all p > 0.99). The reproducibility of duplicate measurements was assessed using each of the B-mode color maps. The coefficient of variation between the two measurements ranged from 6.7% to 9.7%. These variations were not significantly different between each map or gray scale (p > 0.24). In conclusion, B-mode color maps do not distort ultrasound measurements of far wall thickness of the common carotid artery. The reproducibility of these measurements is neither significantly nor usefully improved by using different color maps. Because no additional information is obtained, the use of color may not be warranted.

Adult↗

PubMed2004

Reproducibility of electromyography and ground reaction force during various running techniques.

This study examined the validity of the assumption of electromyographic (EMG) and vertical ground reaction force (GRF) parameter reproducibility during running at different velocities and stride frequencies. Each of 12 female long distance runners ran on a treadmill in combinations of three velocities (2.5, 3.0 and 3.5 m/s) and three stride frequencies (preferred, +/-10% from preferred). Seven parameters from the GRF and five parameters from the EMG signals from five muscles of the lower extremity were evaluated (1000 Hz). The GRF was analysed by a pressure measuring insoles. A total number of three trials for each running condition were recorded. GRF parameters during all running conditions showed high intraclass correlation coefficients (ICC average 0.87). The ICC of the EMG parameters of gastrocnemius medialis and lateralis were high (r>0.69 in 73% of the data), while those for vastus lateralis (22%), hamstrings (42%) and tibialis anterior (51%) were clearly lower. The results revealed that GRF parameters were reproducible during all running techniques indicating that a single trial would provide reproducible GRF-data. The reproducibility of the EMG parameters was not influenced by the running technique but dependent on the parameter itself and on the muscle studied.

Adult↗

PubMed1999

Reproducibility study of TLD-100 micro-cubes at radiotherapy dose level.

The precision of the thermoluminescent response of Harshaw micro-cube dosimeters (TLD-100), evaluated in both Harshaw thermoluminescent readers 5500 and 3500, for 1 Gy dose value, was investigated. The mean reproducibility for micro-cubes, pre-readout annealed at 100 degrees C for 15 min, evaluated with the manual planchet reader 3500, is 0.61% (1 standard deviation). When micro-cubes are evaluated with the automated hot-gas reader 5500, reproducibility values are undoubtedly worse, mean reproducibility for numerically stabilised dosimeters being equal to 3.27% (1 standard deviation). These results indicate that the reader model 5500, or, at least, the instrument used for the present measurements, is not adequate for micro-cube evaluation, if precise and accurate dosimetry is required. The difference in precision is apparently due to geometry inconsistencies in the orientation of the imperfect micro-cube faces during readout, requiring careful and manual reproducible arrangement of the selected micro-cube faces in contact with the manual reader planchet.

Evaluation Studies as Topic↗