Exposure Control Methods Research Articles

A temporal evaluation of respirable crystalline silica exposure for construction tasks.

Personal air monitoring using a TSI SidePak AM520 personal aerosol monitor was performed on a northern Colorado construction site during five tasks from the OSHA Table 1: Specified Exposure Control Methods When Working With Materials Containing Crystalline Silica to estimate silica dust concentrations in real time. Photometric measurements were modified using a gravimetric correction factor and a % respirable crystalline silica adjustment. Each task was sampled once; sample time ranged from 14 min to 40 min, with a mean sample time of 27 min. The mean silica dust concentration estimates (μg/m3) (standard deviation [SD]) for the five tasks computed from the TSI SidePak AM520 respirable dust measurements were core drilling 12 μg/m3 [2.46], grinding 918 μg/m3 [1134.08], cutting with a walk-behind saw 36 μg/m3 [79.67], jackhammering 27 μg/m3 [23.24], and dowel drilling 66 μg/m3 [77.65]. Silica exposure estimates from real-time monitoring can be used to identify exposures that may be related to inadequate controls or worker behaviors that contribute to peak exposures. Respirable crystalline silica exposure estimates presented here are likely not generalizable to other construction sites or tasks.

Item exposure and utilization control methods for optimal test assembly

Exposure control is an important component of computerized adaptive testing. Exposure control is often used to secure test content by preventing item overexposure, and also to balance item utilization by avoiding item underexposure. Content balancing is another important component of computerized adaptive testing. The shadow-test approach to content balancing has many practical merits, including that it ensures complete satisfaction of all content requirements in every assembled test. Several exposure control methods have been developed over the years. The current study describes modifications to existing exposure control methods for use with shadow-test-based adaptive testing, with the objective of achieving bidirectional exposure control. The performances of the modified methods were compared with respect to item exposure and utilization along with ability estimation accuracy. For the purpose of comparison, a Monte Carlo simulation was performed using realistic item pools and content constraints. Implications for real-world applications are discussed.

Comparison of virus aerosol concentrations across a face shield worn on a healthcare personnel during a simulated patient cough.

Patients diagnosed with coronavirus disease 2019 (COVID-19) aerosolize severe acute respiratory coronavirus virus 2 (SARS-CoV-2) via respiratory efforts, expose, and possibly infect healthcare personnel (HCP). To prevent transmission of SARS-CoV-2 HCP have been required to wear personal protective equipment (PPE) during patient care. Early in the COVID-19 pandemic, face shields were used as an approach to control HCP exposure to SARS-CoV-2, including eye protection. An MS2 bacteriophage was used as a surrogate for SARS-CoV-2 and was aerosolized using a coughing machine. A simulated HCP wearing a disposable plastic face shield was placed 0.41 m (16 inches) away from the coughing machine. The aerosolized virus was sampled using SKC biosamplers on the inside (near the mouth of the simulated HCP) and the outside of the face shield. The aerosolized virus collected by the SKC Biosampler was analyzed using a viability assay. Optical particle counters (OPCs) were placed next to the biosamplers to measure the particle concentration. There was a statistically significant reduction (P < .0006) in viable virus concentration on the inside of the face shield compared to the outside of the face shield. The particle concentration was significantly lower on the inside of the face shield compared to the outside of the face shield for 12 of the 16 particle sizes measured (P < .05). Reductions in virus and particle concentrations were observed on the inside of the face shield; however, viable virus was measured on the inside of the face shield, in the breathing zone of the HCP. Therefore, other exposure control methods need to be used to prevent transmission from virus aerosol.

Automatic exposure control method for 3D shape measurement of specular surface based on digital fringe projection

Digital fringe projection (DFP) is widely applied in three-dimensional (3D) shape measurements. However, its performance is severely disturbed while measuring complex surfaces with an extensive range of reflectivity. In this paper, to enhance the underexposed regions and reduce the saturated regions, an automatic and effective method is proposed for the multi-exposure determination of the DFP system. During the whole process, only one unsaturated image must be captured preliminarily, which could establish an adaptive strategy based on the intensity value distribution function. Raw absolute phase maps captured with different exposure times are synthesized at the pixel level for phase retrieval and 3D reconstruction. To evaluate the effectiveness of our method, a high dynamic range method and a global optimal exposure method are introduced for comparison. Verification experiments demonstrate that our method performs better for the 3D reconstruction results of complex surfaces with a large reflectivity range.

Automated Camera Exposure Control for Accuracy-Enhanced Stereo-Digital Image Correlation Measurement.

An automated camera exposure control method, which allows a two-camera stereo-digital image correlation (stereo-DIC) system to capture high-quality speckle image pairs, is presented for accuracy-enhanced stereo-DIC measurement. By using this method, the two synchronized cameras can automatically determine the optimal camera exposure and ideal average grayscale for capturing the optimal reference image pair in the reference state. Furthermore, high-quality deformed image pairs can be recorded during the test by adaptively adjusting the camera exposure in case of serious ambient light variations. Validation tests, including varying illumination tests and translation tests, were performed to verify the effectiveness and robustness of this method. Experimental results indicate that the proposed method overperforms the existing stereo-DIC technique with empirically determined fixed camera exposure time. The practicality of the proposed automated camera exposure control method was verified using real high-temperature experiments.

Computerized Adaptive Testing for Ipsative Tests with Multidimensional Pairwise-Comparison Items: Algorithm Development and Applications.

A computerized adaptive testing (CAT) solution for tests with multidimensional pairwise-comparison (MPC) items, aiming to measure career interest, value, and personality, is rare. This paper proposes new item selection and exposure control methods for CAT with dichotomous and polytomous MPC items and present simulation study results. The results show that the procedures are effective in selecting items and controlling within-person statement exposure with no loss of efficiency. Implications are discussed in two applications of the proposed CAT procedures: a work attitude test with dichotomous MPC items and a career interest assessment with polytomous MPC items.

Optimisation of CT protocols in PET-CT across different scanner models using different automatic exposure control methods and iterative reconstruction algorithms

BackgroundA significant proportion of the radiation dose from a PET-CT examination is dependent on the CT protocol, which should be optimised for clinical purposes. Matching protocols on different scanners within an imaging centre is important for the consistency of image quality and dose. This paper describes our experience translating low-dose CT protocols between scanner models utilising different automatic exposure control (AEC) methods and reconstruction algorithms.MethodsThe scanners investigated were a newly installed Siemens Biograph mCT PET with 64-slice SOMATOM Definition AS CT using sinogram affirmed iterative reconstruction (SAFIRE) and two GE Discovery 710 PET scanners with 128-slice Optima 660 CT using adaptive statistical reconstruction (ASiR). Following exploratory phantom work, 33 adult patients of various sizes were scanned using the Siemens scanner and matched to patients scanned using our established GE protocol to give 33 patient pairs. A comparison of volumetric CT dose index (CTDIvol) and image noise within these patient pairs informed optimisation, specifically for obese patients. Another matched patient study containing 27 patient pairs was used to confirm protocol matching. Size-specific dose estimates (SSDEs) were calculated for patients in the second cohort. With the acquisition protocol for the Siemens scanner determined, clinicians visually graded the images to identify optimal reconstruction parameters.ResultsIn the first matched patient study, the mean percentage difference in CTDIvol for Siemens compared to GE was − 10.7% (range − 41.7 to 50.1%), and the mean percentage difference in noise measured in the patients’ liver was 7.6% (range − 31.0 to 76.8%). In the second matched patient study, the mean percentage difference in CTDIvol for Siemens compared to GE was − 20.5% (range − 43.1 to 1.9%), and the mean percentage difference in noise was 19.8% (range − 27.0 to 146.8%). For these patients, the mean SSDEs for patients scanned on the Siemens and GE scanners were 3.27 (range 2.83 to 4.22) mGy and 4.09 (range 2.81 to 4.82) mGy, respectively. The analysis of the visual grading study indicated no preference for any of the SAFIRE strengths.ConclusionsGiven the different implementations of acquisition parameters and reconstruction algorithms between vendors, careful consideration is required to ensure optimisation and standardisation of protocols.

Contamination of lenalidomide on blister packages after administration and its exposure countermeasures

Background: Reliable exposure control measures are needed to avoid occupational exposures from hazardous drugs. However, there is little information on blister packages concerning exposure. We investigated the contamination and exposure control methods of lenalidomide. Materials and Methods: Nine facilities involved with the RevMate program (the Japanese REMS program) participated in this study. Blister packages (10 capsules/ sheet, no cuts) were collected from each institution after the administration of 5-mg Revlimid capsules. Additionally, the safety performance of different gloves was tested. Results: A total of 18 samples were analyzed and the results revealed that all samples were contaminated with lenalidomide. Our questionnaire revealed that all pharmacists handled the blister packages with their bare hands when they were checking the remaining capsules of lenalidomide. We analyzed gloves made from four different materials (nitrile, polyvinyl chloride, latex, and polyethylene) and found no permeability in any glove type. Conclusion: We conclude that the spent blister package is a potential source of exposure to lenalidomide. All medical staff and caregivers should wear gloves when they handle lenalidomide.

Assessment of dust exposure and chronic respiratory symptoms among workers in medium scale woodwork factories in Ethiopia; a cross sectional study

BackgroundWood dust in a form of inhalable particulates can penetrate the lung tissues and affect respiratory health. Woodwork factory workers are at a greater risk of developing respiratory health problems because of exposure in their working environment, but existing data were few. The aim of this study was to assess the prevalence of chronic respiratory symptoms, associated factors, and concentration of personal total wood dust level among medium-scale woodwork factory workers.MethodsAn institutional based cross-sectional study was conducted among 506 woodwork factory workers. We selected study participants using a simple random sampling technique. We assessed chronic respiratory symptoms using the British Medical Research Council respiratory symptoms questionnaire with a few modifications. A multivariate logistic regression model was used to identify the factors. Forty dust measurements were collected from 20 randomly selected workers using a closed-face cassette (CFC) personal sampler. We analyzed the dust samples gravimetrically using a standard microbalance scale.ResultsWe recruited a random sample of 506 workers in the study with a response rate of 98%. The prevalence of chronic respiratory health symptoms among woodworkers was 69.8% with a prevalence of cough (54.6%), phlegm (52.2%), wheezing (44.6%), breathlessness (42.1%), and chest pain (42.9%). Past occupational dust exposure history (AOR = 2.09, 95% CI; 1.09–4.01), work experience > 5 years (AOR = 9.18, 95% CI; 5.27–16.00), using bio-fuel as energy for cooking (AOR = 2.42, 95% CI; 1.44–4.07), and having no occupational safety and health training (AOR = 3.38, 95% CI; 1.20–9.49) were factors that significantly associated with chronic respiratory symptoms among woodwork workers. The geometric mean (GM) of dust exposure level among woodworkers was 10.27 mg/m3, which exceeded the limit of 10 mg/m3 set by the ACGIH.ConclusionsHigh prevalence of chronic respiratory symptoms was reported from woodwork factory workers. Increased work- experience, using bio-fuel as an energy source for cooking, past occupational dust exposure history, and having no occupational safety and health training were identified risk factors. The measured average personal wood dust exposure level was above the recommended occupational threshold limit value. Therefore, workers’ wood dust exposure reduction and control methods and respiratory health awareness programs should be implemented.

Adaptive magnetorheological energy absorber control method for drop-induced shock mitigation

This paper presents a minimum duration deceleration exposure (MDDE) control method for drop-induced shock mitigation system using a magnetorheological energy absorber (MREA) at high sink rates. The key MDDE control goal is that the payload should come to rest after fully using the available MREA stroke, that is, to accomplish a soft landing, without exceeding the maximum allowable deceleration and simultaneously minimizing the duration of exposure to the maximum allowable deceleration. The MDDE control algorithm is developed as follows for a given available stroke. The payload deceleration is initially set to the maximum allowable value and held constant until the remaining damper stroke and payload velocity are such that the Bingham number control can be used for the terminal trajectory to ensure a soft landing. The sink rate range of the MDDE control is calculated and the results show that the MDDE control can be utilized at high sink rates, whereas prior Bingham number control can be used only at sufficiently low sink rates without violating the maximum allowable deceleration constraint. An optimal criterion to switch from the BN control method to MDDE control method is developed. Finally, the optimal control method is applied for a helicopter seat suspension system by optimal selection criterion to automatically accommodate varying sink rate (drop velocity) and occupant weight.

Chronic respiratory symptoms, lung function and associated factors among flour mill factory workers in Hawassa city, southern Ethiopia: \u201ccomparative cross-sectional study\u201d

BackgroundOccupational related respiratory diseases arise as a result of the deposition of dust particles in the lungs. Flour milling industries; generate organic dust during industrial processes, such as cleaning, milling, packaging, and loading which release dust into the air and later inhaled by workers. Flour mill workers are at risk of developing respiratory health problems because of exposure in their working environment, but existing data were few. The aim of this study was to assess the prevalence of chronic respiratory symptoms, lung function and associated factors among flour mill factory workers.MethodsA comparative cross-sectional study was conducted among 196 flour mill factory workers and 210 soft drinks factory workers. We selected study participants using a systematic sampling technique. We assessed the chronic respiratory symptoms using the questionnaire adopted from the British Medical Research Council. Binary logistic regression analysis with 95% CI and p < 0.05 was used to identify the factors. Lung function parameters; Forced Vital Capacity (FVC), Forced Expiratory Volume in one second (FEV1) and ratio FEV1/FVC was measured by using spirometer and analyzed by using an independent t-test.ResultsWe included 406 (96.7%) workers in this study. The prevalence of chronic respiratory symptoms was higher among flour mill workers as compared to soft-drinks factory workers (56.6% vs.12.9%). Primary education (AOR = 5.8, 95% CI, 1.3–23.2), mixing department (AOR = 5.3, 95% CI = 1.68–16.56), work experience 6–9 years (AOR = 5.1, 95% CI = 2.05–12.48), work experience ≥10 years (AOR = 2.5, 95% CI = 1.01–6.11) and working over eight hours (AOR = 2.4, 95% CI, 1.16–5.10) were factors that significantly associated with chronic respiratory symptoms among flour mill workers. FVC (p < 0.002), FEV1 (p < 0.001) and FEV1/FVC (p < 0.012) were significantly reduced among flour mill workers.ConclusionsWe found chronic respiratory symptoms to be high among flour mill workers. Lower education level, mixing department, increased work experience, and longer working hours were identified factors. The flour mill dust exposed worker’s lung function parameters were highly reduced. This study suggested that workers’ dust exposure reduction and control methods in flour mill factories need to be implemented.

The Effect of Item Exposure Control Methods on Measurement Precision and Test Security under Different Measurement Conditions in Computerized Adaptive Testing

In this research, it was aimed to investigate the effect of item exposure control methods on measurement precision and test security for dichotomous items within different conditions (different ability distributions, test lengths, sample sizes) in computerized adaptive testing applications. Current research is designed as a Monte Carlo simulation research. Within the scope of the research, short test was designed to have 25 items while long test was designed to have 50 items. In addition to this, small sample was simulated to have 250 observations whereas large sample was simulated to have 1000 observations. Regarding the test-takers’ ability parameters, computerized adaptive testing samples which have normal, right-skewed, left-skewed and uniform distribution for each sample size condition in which ability parameters were within -3 and +3 range were generated. The condition in which item exposure was not controlled for was taken as the reference condition and Sympson Hetter and Fade Away methods were compared with the reference condition. When the variables and conditions within the research were crossed, 48 simulation conditions were established and 4800 data files were generated by doing 100 replications for each condition. Measurement precision and test security indices computed for each condition were compared to one another. The analyses conducted indicate that measurement precision indices corresponding to the different item exposure control conditions did not create substantial differences. It was found out that when Fade Away method was used, item exposure was distributed in a balanced way and higher test security was obtained. As a consequence of this, it was concluded that item pool became more effective and sustainable without revelation (disclosure) of the items. Accordingly, it was discovered that in computerized adaptive testing applications in different conditions, instead of Sympson Hetter method which is frequently used before computerized adaptive testing applications and in which item exposure control parameters are estimated by iterative simulations, the use of Fade Away method which ensures the item exposure control parameters to be estimated simultaneously resulted in higher test security without reducing the measurement precision.

Item Selection and Exposure Control Methods for Computerized Adaptive Testing with Multidimensional Ranking Items

AbstractThe use of computerized adaptive testing algorithms for ranking items (e.g., college preferences, career choices) involves two major challenges: unacceptably high computation times (selecting from a large item pool with many dimensions) and biased results (enhanced preferences or intensified examinee responses because of repeated statements across items). To address these issues, we introduce subpool partition strategies for item selection and within‐person statement exposure control procedures. Simulations showed that the multinomial method reduces computation time while maintaining measurement precision. Both the freeze and revised Sympson‐Hetter online (RSHO) methods controlled the statement exposure rate; RSHO sacrificed some measurement precision but increased pool use. Furthermore, preventing a statement's repetition on consecutive items neither hindered the effectiveness of the freeze or RSHO method nor reduced measurement precision.

Ergonomic endoscopy: An oxymoron or realistic goal?

The current endoscope design is not ergonomic. There is a high prevalence of endoscopy-related injury reported in the literature, and studies have demonstrated high-risk biomechanical exposures during the performance of routine colonoscopy. Endoscopy ergonomics focuses on understanding the endoscopist's interaction with the endoscope and the endoscopy unit and re-designing these tasks to minimize the risk of endoscopy-related injury. The discussion to date has focused on what the endoscopist can do to minimize his or her risk of injury. It is imperative that we re-frame that discussion because the implication that physicians are responsible for implementing personal or workplace interventions places an undue burden on physicians and will be the least effective exposure control method. Endoscope companies need to consider the endoscopist in their design process. As a profession, we need to collectively advocate for endoscopist safety. We offer a perspective on how ergonomic endoscopy can become a realistic and achievable goal.

The Asymptotic Distribution of Average Test Overlap Rate in Computerized Adaptive Testing.

The average test overlap rate is often computed and reported as a measure of test security risk or item pool utilization of a computerized adaptive test (CAT). Despite the prevalent use of this sample statistic in both literature and operations, its sampling distribution has never been known nor studied in earnest. In response, a proof is presented for the asymptotic distribution of a linear transformation of the average test overlap rate in fixed-length CAT. The theoretical results enable the estimation of standard error and construction of confidence intervals. Moreover, a practical simulation study demonstrates the statistical comparison of average test overlap rates between two CAT designs with different exposure control methods.

Predictive model of biological equivalent radiofrequency electromagnetic field exposure assessment

Introduction. The issues of radiofrequency electromagnetic field in near field human body exposure correct assessment and control methods improvement actualization determined the need to develop a predictive model that provides different exposure conditions in terms of their biological equivalence comparison.Materials and methods. The problem of laboratory rats and humans equivalent EMF exposure assessment in near and far fields was considered. It is proposed to use a set of criteria that include both the power absorption in the irradiated objects values and the exposure time, allowing to take into account the peculiarities of human body and animals species sensitivity to this factor to solve this problem.Results. Relations for RF EMF equivalent levels values calculation for concrete biological object in near and far fields are presented. There are presented the ratio to calculate EMF levels in terms of power density and energy exposure to case of human body exposure that is equivalent to experimental conditions of rats exposure.Discussion. The developed model can be used to compare the experimental conditions of exposure in the near field with PD values for far field (formed electromagnetic wave), which is most important for &gt;300 MHz frequencies, as well as for the interpretation of EMF biological effects obtained in animal experiments to human exposure conditions assess. This provides a biologically based approach to control RF EMF intensity at any distance from the source and the comparison of the field strength levels with the PD values in the zone of the formed electromagnetic wave.Conclusion. The proposed model takes into account the physical patterns of energy absorption in different objects and differences of organisms species sensitivity to factor exposure; provides the ability to predict critical levels of irradiation for different human body organs and systems, taking into account the time of the factor exposure too.

An Investigation of Exposure Control Methods With Variable-Length CAT Using the Partial Credit Model.

The purpose of this simulation study was to investigate the effect of several different item exposure control procedures in computerized adaptive testing (CAT) with variable-length stopping rules using the partial credit model. Previous simulation studies on CAT exposure control methods with polytomous items rarely considered variable-length tests. The four exposure control techniques examined were the randomesque with a group of three items, randomesque with a group of six items, progressive-restricted standard error (PR-SE), and no exposure control. The two variable-length stopping rules included were the SE and predicted standard error reduction (PSER), along with three item pools of varied sizes (43, 86, and 172 items). Descriptive statistics on number of nonconvergent cases, measurement precision, testing burden, item overlap, item exposure, and pool utilization were calculated. Results revealed that the PSER stopping rule administered fewer items on average while maintaining measurement precision similar to the SE stopping rule across the different item pool sizes and exposure controls. The PR-SE exposure control procedure surpassed the randomesque methods by further reducing test overlap, maintaining maximum exposure rates at the target rate or lower, and utilizing all items from the pool with a minimal increase in number of items administered and nonconvergent cases.

Can TIMSS Mathematics Assessments be Implemented as a Computerized Adaptive Test?

In recent years, there has been a growing interest and extensive use of computerized adaptive testing (CAT) especially in large-scale assessments. Numerous simulation studies have been conducted on both real and simulated data sets to determine the optimum conditions and develop CAT versions. Being one of the most popular large-scale assessment programs, Trends in International Mathematics and Science Study (TIMSS) has been implemented as paper and pencil tests to monitor student achievement in mathematics and science at fourth and eighth grade levels since 1995. The purpose of this study is to investigate the optimum CAT algorithm for TIMSS eighth grade mathematics assessments. Since Turkey and USA participated in 2007, 2011 and 2015 administrations, their data were combined and then 393 items were calibrated on the same scale by using marginal maximum likelihood estimation method. With this item pool, several scenarios were proposed and tested to determine not only the optimum starting rule, ability estimation method, test termination rule but also the efficiency of exposure control method. The results of the study indicated that estimating abilities with expected a posteriori method after 6 random items, terminating the fixed-length test after 20 items seemed to be the optimum algorithm for TIMSS eighth grade mathematics assessments. Also, it was found that using item exposure control had a prior importance for the effective use of the item pool. This study has some implications for both national and international large-scale test developers in determining the optimum CAT algorithm and its consequences compared with paper and pencil versions.

CT automated exposure control using a generalized detectability index

Identifying an appropriate tube current setting can be challenging when using iterative reconstruction due to the varying relationship between spatial resolution, contrast, noise, and dose across different algorithms. This study developed and investigated the application of a generalized detectability index ( ) to determine the noise parameter to input to existing automated exposure control (AEC) systems to provide consistent image quality (IQ) across different reconstruction approaches. This study proposes a task-based automated exposure control (AEC) method using a generalized detectability index ( ). The proposed method leverages existing AEC methods that are based on a prescribed noise level. The generalized metric is calculated using lookup tables of task-based modulation transfer function (MTF) and noise power spectrum (NPS). To generate the lookup tables, the American College of Radiology CT accreditation phantom was scanned on a multidetector CT scanner (Revolution CT, GE Healthcare) at 120kV and tube current varied manually from 20 to 240mAs. Images were reconstructed using a reference reconstruction algorithm and four levels of an in-house iterative reconstruction algorithm with different regularization strengths (IR1-IR4). The task-based MTF and NPS were estimated from the measured images to create lookup tables of scaling factors that convert between and noise standard deviation. The performance of the proposed -AEC method in providing a desired IQ level over a range of iterative reconstruction algorithms was evaluated using the American College of Radiology (ACR) phantom with elliptical shell and using a human reader evaluation on anthropomorphic phantom images. The study of the ACR phantom with elliptical shell demonstrated reasonable agreement between the predicted by the lookup table and measured in the images, with a mean absolute error of 15% across all dose levels and maximum error of 45% at the lowest dose level with the elliptical shell. For the anthropomorphic phantom study, the mean reader scores for images resulting from the -AEC method were 3.3 (reference image), 3.5 (IR1), 3.6 (IR2), 3.5 (IR3), and 2.2 (IR4). When using the -AEC method, the observers' IQ scores for the reference reconstruction were statistical equivalent to the scores for IR1, IR2, and IR3 iterative reconstructions (P>0.35). The -AEC method achieved this equivalent IQ at lower dose for the IR scans compared to the reference scans. A novel AEC method, based on a generalized detectability index, was investigated. The proposed method can be used with some existing AEC systems to derive the tube current profile for iterative reconstruction algorithms. The results provide preliminary evidence that the proposed -AEC can produce similar IQ across different iterative reconstruction approaches at different dose levels.

Investigating The Effect of Exposure-Control Strategies on Item Selection Methods in MCAT

This study aims to investigate the effect of different item exposure controlling strategies on item selection methods in the context of multidimensional computerized adaptive testing (MCAT). Additionally, this study aims to examine to what extend the restrictive threshold (RT) and the restrictive progressive (RPG) exposure methods suppress the item exposure rates and increase the exposure rates of underexposed items without losing psychometric precision in MCAT. For this purpose, the performance of four item selection methods with and without exposure controls are evaluated and compared so as to determine how results differ when item exposure controlling strategies are applied with Monte-Carlo simulation method. The four item selection methods employed in this study are D-optimality, Kullback–Leibler information (KLP), the minimized error variance of linear combination score with equal weight (V1), the composite score with optimized weight (V2). On the other hand, the maximum priority index (MPI) method proposed for unidimensional CAT and two other item exposure control methods, that are RT and RPG methods proposed for cognitive diagnostic CAT, are adopted. The results show that: (1) KLP, D-optimality, and V1 performed better in recovering domain scores, and all outperformed V2 with respect to precision; (2) although V1 and V2 offer improved item bank usage rates, KLP, D-optimality, V1, and V2 produced an unbalanced distribution of item exposure rates; (3) all exposure control strategies improve the exposure uniformity greatly and with very little loss in psychometric precision; (4) RPG and MPI perform similarly in exposure control, and outperformed RT exposure control method.