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Results for “Error minimization”

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At least 595 records · Page 33Linked to original sources

PubMed1997

Improved method for single-bolus kinetic measurements using a noncleared reference indicator.

After intravenous injection of a tracer as a single bolus, its concentration decreases as it mixes with the plasma, disperses throughout the circulation, and enters body pools. Kinetic values that are dependent on early concentrations may be in considerable error because mixing is not instantaneous throughout the circulation, and this problem is particularly acute in the mammalian fetus, with its distinctive circulatory pattern. To minimize this error, a method was developed in which the noncleared reference tracer 125I-labeled albumin was injected together with a representative, rapidly cleared metabolite 14C-labeled palmitic acid, and the former was used to correct for mixing delay. A total of 19 disappearance curves were studied after intravenous injection into seven near-term fetal sheep. Kinetic values were calculated with and without correction for mixing delay. Taking account of mixing delay increased the calculated volume of distribution 41% [from 44 +/- 4 (SE) to 62 +/- 3 ml/kg, P < 0.001], increased plasma clearance rate 13% (from 41 +/- 2 to 47 +/- 1 ml-min-1.kg-1, P < 0.002), decreased the rate constant for irreversible loss 26% (from 1.05 +/- 0.07 to 0.78 +/- 0.04 min-1, P < 0.001), and increased the calculated effective half-life 26% (0.71 +/- 0.06 to 0.90 +/- 0.05 min, P < 0.001). Thus use of the additional reference marker significantly altered calculated results and provided values believed to more accurately describe rapid disappearance from the central mixing compartment into metabolic pools.

Animals↗

PubMed1994

In vivo estimation of body composition of mature gilts using live weight, backfat thickness, and deuterium oxide.

Thirty-seven Duroc x (Yorkshire x Landrace) (DYL) and 21 Yorkshire x Landrace (YL) gilts were used to develop equations that predict body composition of replacement-age breeding swine. Before slaughter, gilts were weighed, ultrasonically scanned for 10th rib backfat thickness, and infused with D2O (.25 g/kg live weight). The D2O space (kilograms) was calculated from body water D2O concentration determined at equilibrium (150 and 210 min after infusion). Regression models predicting empty body (Eb) components for DYL and YL groups were fitted using all possible variable combinations (D2O space, live weight, and[or] backfat depth). Variables selected in best-fit models for Eb water, protein, fat, and ash for data from DYL gilts differed from variables selected from data from YL gilts. Average prediction errors (kilograms; [predicted residual sum of squares divided by n]1/2) of best-fit equations were 2.37, 2.03 (Eb weight), 2.36, 1.66 (Eb water), 1.07, .47 (Eb protein), and 2.76, 2.89 (Eb fat) for DYL and YL data sets, respectively. Cross-validation by applying DYL equations to YL data, and vice versa, resulted in larger prediction errors. Likewise, larger errors were obtained when equations published elsewhere were applied to DYL and YL data sets. No cited source provided a set of equations that consistently minimized prediction errors of all Eb components of both DYL and YL gilts. Results indicate that prediction equations using D2O space, live weight, and(or) backfat thickness are accurate in estimating body composition only in animals physiologically resemble the population in which the equations were derived.

Adipose Tissue↗

PubMed1999

Pitfalls in Doppler evaluation of diastolic function: insights from 3-dimensional magnetic resonance imaging.

Ultrasound-Doppler assessment of diastolic function is subject to velocity errors caused by angle sensitivity and a fixed location of the sample volume. We used 3-dimensional phase contrast magnetic resonance imaging (MRI) to evaluate these errors in 10 patients with hypertension and in 10 healthy volunteers. The single (Doppler) and triple (MRI) component velocity was measured at early (E) and late (A) inflow along Doppler-like sample lines or 3-dimensional particle traces generated from the MRI data. Doppler measurements underestimated MRI velocities by 9.4% +/- 8.6%; the effect on the E/A ratio was larger and more variable. Measuring early and late diastolic inflows from a single line demonstrated the error caused by their 3-dimensional spatial offset. Both errors were minimized by calculating the E/A ratio from maximal E and A values without constraint to a single line. Alignment and spatial offset are important sources of error in Doppler diastolic parameters. Improved accuracy may be achieved with the use of maximal E and A velocities from wherever they occur in the left ventricle.

Adult↗

PubMed2002

Optimal design of radioactive particle tracking experiments for flow mapping in opaque multiphase reactors.

In the past decade, radioactive particle tracking techniques have emerged in the field of chemical engineering and have become increasingly popular for non-invasive flow mapping of the hydrodynamics in multiphase reactors. Based on gamma-ray sensitization of an array of scintillation detectors, the Computer Automated Radioactive Particle Tracking (CARPT) technique measures flow fields by monitoring the actual motion path of a single discrete radioactive flow follower which has the physical properties of the phase whose motion is being followed. A limitation to the accuracy of CARPT lies in the error associated with the reconstruction of the tracer particle position which affects the space-resolution capability of the technique. It is of interest, therefore, to minimize this error by choosing wisely the best hardware and an optimal configuration of CARPT detectors' array. Such choices are currently based on experience, without firm scientific basis. In this paper, through theoretical modeling and simulation, we describe how the accuracy of a radioactive particle tracking setup may be assessed a priori. Through an example of a proposed implementation of CARPT on a gas-solids riser, we demonstrate how this knowledge can be used for choosing the hardware required for the experiment. Finally, we show how the optimal arrangement of detectors can be effected for maximum accuracy for a given amount of monetary investment for the experiment.

Journal Article↗

PubMedDate not supplied

[Plethysmographic measurement of lung volume in chronic obstructive pulmonary disease. Influence of the panting pattern].

In 9 healthy subjects and 22 patients with chronic obstructive disease, we computed total lung capacity (TLC) using an integrated flow pressure-corrected body plethysmograph. During panting manoeuvre, TLC derived from oesophageal pressure (TLCes) was compared to TLC derived from mouth pressure (TLCm). In healthy subjects, TLCm was identical to TLCes. Patients with obstructive disease exhibited different behaviours according to experimental conditions: a) in free frequency panting with mouth occlusion close to functional residual capacity (FRC) (9 patients), TLCm appeared to be significantly higher than TLCes (mean difference: 0.25 1; p less than 0.05); b) in panting with both low (less than 1 Hz) and high (2 Hz) frequencies and mouth occlusion close to FRC (7 patients), TLCm appeared to be significantly higher than TLCes only at a high frequency (p less than 0.05); c) in panting with both low and high frequencies and mouth occlusion close to TLC (6 patients), no significant difference was observed between TLCm and TLCes. These results suggest that in patients with chronic obstructive disease plethysmographic lung volume measurements are subject to error, due to the influence of extrathoracic airways. During occlusion at FRC, panting frequency was found to influence the results obtained, the error being minimized with low frequencies. In contrast, by occluding at TLC, we found that panting frequency was less likely to influence the results. However, potential sources of error still exist: for instance, the influence of abdominal gas or the panting pattern.

Adult↗

PubMed2000

Enhancing the precision of ECG baseline correction: selective filtering and removal of residual error.

Reemergence of the problem of baseline correction is related to recent advancements in the electrocardiographic (ECG) analysis of beat-to-beat repolarization changes which play an important role in risk assessment and the prediction of sudden cardiac death. These alterations often have an amplitude of a few microvolts and duration of several milliseconds and their detection requires special accuracy of baseline estimation. Using detailed analysis of various types of residual errors we designed a two-step procedure for selective filtering of ECG and removal of residual error with minimal distortion of cardiac complexes and tested this approach on 100 simulated and 210 real ECG signals. Application of this procedure provided a twofold reduction in the error of baseline estimation and T-wave amplitude measurements compared to high-pass filtering. Selective application of this approach to the segments with low baseline drift allowed analysis of low-amplitude, beat-to-beat changes in repolarization during more than 70% of the recording time.

Algorithms↗

PubMed2005

New techniques for imaging, digitization and analysis of three-dimensional neural morphology on multiple scales.

Cognitive impairment in normal aging and neurodegenerative diseases is accompanied by altered morphologies on multiple scales. Understanding of the role of these structural changes in producing functional deficits in brain aging and neuropsychiatric disorders requires accurate three-dimensional representations of neuronal morphology, and realistic biophysical modeling that can directly relate structural changes to altered neuronal firing patterns. To date however, tools capable of resolving, digitizing and analyzing neuronal morphology on both local and global scales, and with sufficient throughput and automation, have been lacking. The precision of existing image analysis-based morphometric tools is restricted at the finest scales, where resolution of fine dendritic features and spine geometry is limited by the skeletonization methods used, and by quantization errors arising from insufficient imaging resolution. We are developing techniques for imaging, reconstruction and analysis of neuronal morphology that capture both local and global structural variation. To minimize quantization error and evaluate more precisely the fine geometry of dendrites and spines, we introduce a new shape analysis technique, the Rayburst sampling algorithm that uses the original grayscale data rather than the segmented images for precise, continuous radius estimation, and multidirectional radius sampling to represent non-circular branch cross-sections and anisotropic structures such as dendritic spine heads, with greater accuracy. We apply the Rayburst technique to 3D neuronal shape analysis at different scales. We reconstruct and digitize entire neurons from stacks of laser-scanning microscopy images, as well as globally complex structures such as multineuron networks and microvascular networks. We also introduce imaging techniques necessary to recover detailed information on three-dimensional mass distribution and surface roughness of amyloid beta plaques from human Alzheimer's disease patients and from the Tg2576 mouse that expresses the "Swedish" mutation of the amyloid precursor protein. By providing true three-dimensional morphometry of complex histologic structures on multiple scales, the tools described in this report will enable multiscale biophysical modeling studies capable of testing potential mechanisms by which altered dendritic structure, spine geometry and network branching patterns that occur in normal aging and in many brain disorders, determine deficits of functions such as working memory and cognition.

Aged↗

PubMed1990

A semiautomated method for measuring brain infarct volume.

An accurate, reproducible method for determining the infarct volumes of gray matter structures is presented for use with presently available image analysis systems. Areas of stained sections with optical densities above that of a threshold value are automatically recognized and measured. This eliminates the potential error and bias inherent in manually delineating infarcted regions. Moreover, the volume of surviving normal gray matter is determined rather than that of the infarct. This approach minimizes the error that is introduced by edema, which distorts and enlarges the infarcted tissue and surrounding white matter.

Animals↗

PubMed1999

Nucleotide analogs and new buffers improve a generalized method to enrich for low abundance mutations.

A high sensitivity method for detecting low level mutations is under development. A PCR reaction is performed in which a restriction site is introduced in wild-type DNA by alteration of specific bases. Digestion of wild-type DNA by the cognate restriction endonuclease (RE) enriches for products with mutations within the recognition site. After reamplification, mutations are identified by a ligation detection reaction (LDR). This PCR/RE/LDR assay was initially used to detect PCR error in known wild-type samples. PCR error was measured in low |Deltap K a| buffers containing tricine, EPPS and citrate, as well as otherwise identical buffers containing Tris. PCR conditions were optimized to minimize PCR error using perfect match primers at the Msp I site in the p53 tumor suppressor gene at codon 248. However, since mutations do not always occur within pre-existing restriction sites, a generalized PCR/RE/LDR method requires the introduction of a new restriction site. In principle, PCR with mismatch primers can alter specific bases in a sequence and generate a new restriction site. However, extension from 3' mismatch primers may generate misextension products. We tested conversion of the Msp I (CCGG) site to a Taq I site (TCGA). Conversion was unsuccessful using a natural base T mismatch primer set. Conversion was successful when modified primers containing the 6 H,8 H -3, 4-dihydropyrimido[4,5- c ][1,2]oxazine-7-one (Q6) base at 3'-ends were used in three cycles of preconversion PCR prior to conversion PCR using the 3' natural base T primers. The ability of the pyrimidine analog Q6 to access both a T-like and C-like tautomer appears to greatly facilitate the conversion.

Base Sequence↗

PubMed2001

Learning to move amid uncertainty.

We studied how subjects learned to make movements against unpredictable perturbations. Twelve healthy human subjects made goal-directed reaching movements in the horizontal plane while holding the handle of a two-joint robotic manipulator. The robot generated viscous force fields that perturbed the limb perpendicular to the desired direction of movement. The amplitude (but not the direction) of the viscous field varied randomly from trial to trial. Systems identification techniques were employed to characterize how subjects adapted to these random perturbations. Subject performance was quantified primarily using the peak deviation from a straight-line hand path. Subjects adapted their arm movements to the sequence of random force-field amplitudes. This adaptive response compensated for the approximate mean from the random sequence of perturbations and did not depend on the statistical distribution of that sequence. Subjects did not adapt by directly counteracting the mean field strength itself on each trial but rather by using information about perturbations and movement errors from a limited number of previous trials to adjust motor commands on subsequent trials. This strategy permitted subjects to achieve near-optimal performance (defined as minimizing movement errors in a least-squares sense) while maintaining computational efficiency. A simple model using information about movement errors and perturbation amplitudes from a single previous trial predicted subject performance in stochastic environments with a high degree of fidelity and further predicted key performance features observed in nonstochastic environments. This suggests that the neural structures modified during motor adaptation require only short-term memory. Explicit representations regarding movements made more than a few trials in the past are not used in generating optimal motor responses on any given trial.

Adaptation, Physiological↗

PubMed2004

Reducing quantitative data errors: tips for clinical researchers.

Data errors, or missing and inaccurate data, can compromise research findings. Steps can be taken before and during data collection, as well as during data entry that will minimize data errors. The purpose of this article is to discuss ways to reduce quantitative data errors through thoughtful planning of the data collection form, careful reviewing of completed data forms in the field and laboratory, and consideration of accurate and efficient data entry with thorough verification methods. Clinical researchers are provided with tips and examples for reducing data errors.

Clinical Nursing Research↗

PubMed1980

Role of heating in non-invasive blood pressure measurements in rats.

The "tail-cuff" technique for indirect blood pressure measurements was standardized, with respect to heating, in experiments on 47 adult Sprague-Dawley rats. The direct, intra-arterial, and the indirect blood pressures were simultaneously obtained. Pulse volume was recorded from the tail by a non-invasive technique, and was controlled by gradual application of heat. It was found that pulse volume and body temperature were poorly related. A stable relation existed, however, between the error in the indirect blood pressure recordings and the pulse volume. The error was minimized, provided that the heating was adjusted to induce a pulse volume of at least 25% of the maximum obtainable value. It was suggested that the validity of the indirect blood pressure recording could be improved, if heat application was regulated on the basis of observations of pulse volume in the tail instead of ambient temperature or body temperature. Errors due to excessive vasoconstriction, or discomfort due to overheating could thereby be minimized.

Animals↗

PubMed1993

Mobile and immobile calcium buffers in bovine adrenal chromaffin cells.

1. The calcium binding capacity (kappa S) of bovine chromaffin cells preloaded with fura-2 was measured during nystatin-perforated-patch recordings. 2. Subsequently, the perforated patch was ruptured to obtain a whole-cell recording situation, and the time course of kappa S was monitored during periods of up to one hour. 3. No rapid change (within 10-20 s) of kappa S was observed upon transition to whole-cell recording, as would be expected, if highly mobile organic anions contributed significantly to calcium buffering. However, approximately half of the cells investigated displayed a drop in kappa S within 2-5 min, indicative of the loss of soluble Ca2+ binding proteins in the range of 7-20 kDa. 4. The average Ca2+ binding capacity (differential ratio of bound calcium over free calcium) was 9 +/- 7 (mean +/- S.E.M.) for the poorly mobile component and 31 +/- 10 for the fixed component. It was concluded that a contribution of 7 from highly mobile buffer would have been detected, if present. Thus, this value can be considered as an upper bound to highly mobile Ca2+ buffer. 5. Both mobile and fixed calcium binding capacity appeared to have relatively low Ca2+ affinity, since kappa S did not change in the range of Ca2+ concentrations between 0.1 and 3 microM. 6. It was found that cellular autofluorescence and contributions to fluorescence of non-hydrolysed or compartmentalized dye contribute a serious error in estimation of kappa S. 'Balanced loading', a degree of fura-2 loading such that the calcium binding capacity of fura-2 equals cellular calcium binding capacity, minimizes these errors. Also, changes in kappa S at the transition from perforated-patch to whole-cell recording can be most faithfully recorded for similar degrees of loading in both situations. 7. Nystatin was found unable to make pores from inside of the plasma membrane of chromaffin cells. With careful preparation and storage the diluted nystatin solution maintained its high activity of membrane perforation for more than one week. 8. An equation for the effective diffusion constant for total cytoplasmic calcium, D'Ca, was derived, which takes into account fixed buffer and poorly mobile buffer as determined, as well as calcium bound to fura-2 and some highly mobile buffers.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

PubMed2006

Practical aspects of (1)H transverse paramagnetic relaxation enhancement measurements on macromolecules.

The use of (1)H transverse paramagnetic relaxation enhancement (PRE) has seen a resurgence in recent years as method for providing long-range distance information for structural studies and as a probe of large amplitude motions and lowly populated transient intermediates in macromolecular association. In this paper we discuss various practical aspects pertaining to accurate measurement of PRE (1)H transverse relaxation rates (Gamma(2)). We first show that accurate Gamma(2) rates can be obtained from a two time-point measurement without requiring any fitting procedures or complicated error estimations, and no additional accuracy is achieved from multiple time-point measurements recorded in the same experiment time. Optimal setting of the two time-points that minimize experimental errors is also discussed. Next we show that the simplistic single time-point measurement that has been commonly used in the literature, can substantially underestimate the true value of Gamma(2), unless a relatively long repetition delay is employed. We then examine the field dependence of Gamma(2), and show that Gamma(2) exhibits only a very weak field dependence at high magnetic fields typically employed in macromolecular studies. The theoretical basis for this observation is discussed. Finally, we investigate the impact of contamination of the paramagnetic sample by trace amounts (5%) of the corresponding diamagnetic species on the accuracy of Gamma(2) measurements. Errors in Gamma(2) introduced by such diamagnetic contamination are potentially sizeable, but can be significantly reduced by using a relatively short time interval for the two time-point Gamma(2) measurement.

Algorithms↗

PubMed1994

[Precision and measurement errors in bone mineral density by dual energy x-ray absorptiometry in mass health examination].

Decreasing mortality and the low birth rates has resulted in a high rate of increase in the elderly population in Japan. Increases in osteoporosis and its complication (fractures) are inevitable among the Japanese elderly. The Ministry of Health and Welfare of Japan and other municipalities are in the process of developing standards for noninvasive and quantitative assessment of bone minerals in mass health examinations in order to prevent osteoporosis fracture in elderly females. Dual energy x-ray absorptiometry (DXA) has undergone development to significantly improve scan speed, image resolution and precision with relatively low exposure to x-rays, and is now considered one of the most suitable instruments to measure bone mineral density (BMD) in both clinical and mass-screening for osteoporosis in population-based mass health examinations in Japan. The purpose of the present study using DXA fixed in a mobile van are: 1) to compare the precision of anteroposterior (AP) and lateral (LT) projections of the lumbar region, and three areas of the proximal femur (neck: NK, trochanter: TR, Ward's triangle: WD); 2) to analyze the physical factors influencing the precision; 3) to study the magnitude of intra- and inter-observer measurement errors and of different sets of regions of interest (ROI) in LT projection; and 4) to examine which measurement items should be selected in mass health examination in order to minimize measurement errors particularly for longitudinal observational study. Results are as follow: 1) Precision estimated by the reproducibility of measurements in the spine phantom bone were relatively good in both short and long terms. However, in female volunteers, precision of LT-BMD was remarkably inferior to that for AP-BMD and the three BMD of the proximal femoral region. Among the physical characteristics, body mass index and menopausal state were significantly associated to the precision of LT-BMD. 2) Regarding the correlations of BMD in the same region, all correlation coefficients except LT-BMD (r = 0.65) exceeded 0.97. Intra-regional BMD showed that correlations when including LT-BMD were significantly lower than the other correlations with LT-BMD excluded. 3) Concerning the magnitude of observational errors in both intra- and inter-observer measurements, LT-BMD showed the largest measurement error, largely due to lack of consensus in the ROI setting for the vertebral body and to the instability of positioning when lateral scanning was carried out.(ABSTRACT TRUNCATED AT 400 WORDS)

Absorptiometry, Photon↗

PubMed2001

Performance of time-frequency representation techniques to measure blood flow turbulence with pulsed-wave Doppler ultrasound.

The current processing performed by commercial instruments to obtain the time-frequency representation (TFR) of pulsed-wave Doppler signals may not be adequate to characterize turbulent flow motions. The assessment of the intensity of turbulence is of high clinical importance and measuring high-frequency (small-scale) flow motions, using Doppler ultrasound (US), is a difficult problem that has been studied very little. The objective was to optimize the performance of the spectrogram (SPEC), autoregressive modeling (AR), Choi-Williams distribution (CWD), Choi-Williams reduced interference distribution (CW-RID), Bessel distribution (BD), and matching pursuit method (MP) for mean velocity waveform estimation and turbulence detection. The intensity of turbulence was measured from the fluctuations of the Doppler mean velocity obtained from a simulation model under pulsatile flow. The Kolmogorov spectrum, which is used to determine the frequency of the fluctuations and, thus, the scale of the turbulent motions, was also computed for each method. The best set of parameters for each TFR method was determined by minimizing the error of the absolute frequency fluctuations and Kolmogorov spectral bandwidth measured from the simulated and computed Doppler spectra. The results showed that different parameters must be used for each method to minimize the velocity variance of the estimator, to optimize the detection of the turbulent frequency fluctuations, and to estimate the Kolmogorov spectrum. To minimize the variance and to measure the absolute turbulent frequency fluctuations, four methods provided similar results: SPEC (10-ms sine-cosine windows), AR (10-ms rectangular windows, model order = 8), CWD (w(N) and w(M) = 10-ms rectangular windows, sigma = 0.01), and BD (w(N) = 10-ms rectangular windows, alpha = 16). The velocity variance in the absence of turbulence was on the order of 0.04 m/s (coefficient of variation ranging from 8.0% to 14.5%, depending on the method). With these spectral techniques, the peak of the turbulence intensity was adequately estimated (velocity bias < 0.01 m/s). To track the frequency of turbulence, the best method was BD (w(N) = 2-ms rectangular windows, alpha = 2). The bias in the estimate of the -10 dB bandwidth of the Kolmogorov spectrum was 354 +/- 51 Hz in the absence of turbulence (the true bandwidth should be 0 Hz), and -193 +/- 371 Hz with turbulence (the simulated -10-dB bandwidth was estimated at 1256 Hz instead of 1449 Hz). In conclusion, several TFR methods can be used to measure the magnitude of the turbulent fluctuations. To track eddies ranging from large vortex to small turbulent fluctuations (wide Kolmogorov spectrum), the Bessel distribution with appropriate set of parameters is recommended.

Blood Flow Velocity↗

PubMed2004

Using image and curve registration for measuring the goodness of fit of spatial and temporal predictions.

Conventional measures of model fit for indexed data (e.g., time series or spatial data) summarize errors in y, for instance by integrating (or summing) the squared difference between predicted and measured values over a range of x. We propose an approach which recognizes that errors can occur in the x-direction as well. Instead of just measuring the difference between the predictions and observations at each site (or time), we first "deform" the predictions, stretching or compressing along the x-direction or directions, so as to improve the agreement between the observations and the deformed predictions. Error is then summarized by (a) the amount of deformation in x, and (b) the remaining difference in y between the data and the deformed predictions (i.e., the residual error in y after the deformation). A parameter, lambda, controls the tradeoff between (a) and (b), so that as lambda-->infinity no deformation is allowed, whereas for lambda=0 the deformation minimizes the errors in y. In some applications, the deformation itself is of interest because it characterizes the (temporal or spatial) structure of the errors. The optimal deformation can be computed by solving a system of nonlinear partial differential equations, or, for a unidimensional index, by using a dynamic programming algorithm. We illustrate the procedure with examples from nonlinear time series and fluid dynamics.

Algorithms↗

PubMed2005

Using Six Sigma to reduce medication errors in a home-delivery pharmacy service.

BACKGROUND: Medco Health Solutions, Inc. conducted a project to reduce medication errors in its home-delivery service, which is composed of eight prescription-processing pharmacies, three dispensing pharmacies, and six call-center pharmacies. IMPLEMENTING THE PROJECT: Medco uses the Six Sigma methodology to reduce process variation, establish procedures to monitor the effectiveness of medication safety programs, and determine when these efforts do not achieve performance goals. A team reviewed the processes in home-delivery pharmacy and suggested strategies to improve the data-collection and medication-dispensing practices. A variety of improvement activities were implemented, including a procedure for developing, reviewing, and enhancing sound-alike/look-alike (SALA) alerts and system enhancements to improve processing consistency across the pharmacies. RESULTS: "External nonconformances" were reduced for several categories of medication errors, including wrong-drug selection (33%), wrong directions (49%), and SALA errors (69%). Control charts demonstrated evidence of sustained process improvement and actual reduction in specific medication error elements. DISCUSSION: Establishing a continuous quality improvement process to ensure that medication errors are minimized is critical to any health care organization providing medication services.

Humans↗