scholarly journals An Improved Model for Evaluating Change in Randomized Pretest, Posttest, Follow-Up Designs

Methodology ◽  
2012 ◽  
Vol 8 (3) ◽  
pp. 97-103 ◽  
Author(s):  
Constance A. Mara ◽  
Robert A. Cribbie ◽  
David B. Flora ◽  
Cathy LaBrish ◽  
Laura Mills ◽  
...  
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Group Differences ◽  
Primary Research ◽  
Control Groups ◽  
Proposed Model ◽  
Research Questions ◽  
Improved Model ◽  
And Control

Randomized pretest, posttest, follow-up (RPPF) designs are often used for evaluating the effectiveness of an intervention. These designs typically address two primary research questions: (1) Do the treatment and control groups differ in the amount of change from pretest to posttest? and (2) Do the treatment and control groups differ in the amount of change from posttest to follow-up? This study presents a model for answering these questions and compares it to recently proposed models for analyzing RPPF designs due to Mun, von Eye, and White (2009) using Monte Carlo simulation. The proposed model provides increased power over previous models for evaluating group differences in RPPF designs.

On modeling and dynamics of a multiple launch rocket system

2021 ◽  
pp. 095441002098224
Author(s):  
Bo Li ◽  
Xiaoting Rui ◽  
Guoping Wang ◽  
Jianshu Zhang ◽  
Qinbo Zhou
Keyword(s):  
Monte Carlo ◽  
Multibody Systems ◽  
Euler Method ◽  
Dynamics Analysis ◽  
Analysis Problem ◽  
Dynamic Design ◽  
Proposed Model ◽  
And Control ◽  
Rocket System ◽  
Complete Process

Dynamics analysis is currently a key technique to fully understand the dynamic characteristics of sophisticated mechanical systems because it is a prerequisite for dynamic design and control studies. In this study, a dynamics analysis problem for a multiple launch rocket system (MLRS) is developed. We particularly focus on the deductions of equations governing the motion of the MLRS without rockets by using a transfer matrix method for multibody systems and the motion of rockets via the Newton–Euler method. By combining the two equations, the differential equations of the MLRS are obtained. The complete process of the rockets’ ignition, movement in the barrels, airborne flight, and landing is numerically simulated via the Monte Carlo stochastic method. An experiment is implemented to validate the proposed model and the corresponding numerical results.

A randomized trial of levamisole versus placebo as adjuvant therapy in malignant melanoma.

1991 ◽  
Vol 9 (5) ◽  
pp. 736-740 ◽  
Author(s):  
L E Spitler
Keyword(s):  
Malignant Melanoma ◽  
Adjuvant Therapy ◽  
Randomized Trial ◽  
Control Groups ◽  
Disease Free Interval ◽  
Significant Difference ◽  
Long Term Follow Up ◽  
And Control

We conducted a long-term follow-up (median, 10.5 years) of patients included in a randomized trial of levamisole versus placebo as surgical adjuvant therapy in 203 patients with malignant melanoma. Of the patients randomized, 104 received levamisole, and 99 received placebo. The results show that there is no difference between the treatment and control groups with regard to any of the three end points analyzed. These included disease-free interval, time to appearance of visceral metastasis, and survival. Moreover, there was no significant difference between the treatment and control groups after adjusting for age, sex, or stage of disease.

scholarly journals Striatal glutamate and the conversion to psychosis: a prospective 1H-MRS imaging study

2012 ◽  
Vol 16 (2) ◽  
pp. 471-475 ◽  
Author(s):  
Camilo de la Fuente-Sandoval ◽  
Pablo León-Ortiz ◽  
Mariana Azcárraga ◽  
Rafael Favila ◽  
Sylvana Stephano ◽  
...  
Keyword(s):  
Proton Magnetic Resonance ◽  
Proton Magnetic Resonance Spectroscopy ◽  
Imaging Study ◽  
Psychotic Symptoms ◽  
Resonance Spectroscopy ◽  
Control Groups ◽  
1H Mrs ◽  
Ultra High Risk ◽  
And Control

Abstract Increased glutamate levels in the associative-striatum have been described in subjects at ultra-high risk for psychosis (UHR); nevertheless, it is unclear whether this abnormality predicts the conversion to psychosis. Nineteen subjects at UHR and 26 controls were studied using proton magnetic resonance spectroscopy. Subjects at UHR were clinically followed for 2 yr. Seven UHR subjects (37%) transitioned to a psychotic disorder and the remaining 12 did not exhibit psychotic symptoms at the most recent follow-up. The psychosis transition group had higher glutamate levels compared to both non-transition and control groups (p = 0.02 and p < 0.01, respectively; effect size 1.39). These pilot findings suggest that the conversion to psychosis is associated with increased glutamate levels in the associative-striatum.

scholarly journals The significance of polymorphisms of gene coagulation factors VII and XIII in the pathogenesis of non-traumatic avascular necrosis of the femoral head

2021 ◽  
Vol 27 (1) ◽  
pp. 43-47
Author(s):  
M.A. Panin ◽  
◽  
N.V Zagorodnii ◽  
A.V. Boiko ◽  
L.M. Samokhodskaya ◽  
...  
Keyword(s):  
Femoral Head ◽  
Avascular Necrosis ◽  
Coagulation Factors ◽  
Group Differences ◽  
Unknown Etiology ◽  
Control Group ◽  
Study Group ◽  
Control Groups ◽  
Aseptic Necrosis ◽  
And Control

Introduction Non-traumatic avascular necrosis of the femoral head (ANFH) is a poly-etiologic and socially significant disease in the age of 20 to 50 years and is associated with disability. Research on the identification of necrosis causes/predictors is a relevant issue. Purpose To study the contribution of polymorphisms in the genes of coagulation factors F7 and F13 in the aetiology of non-traumatic avascular necrosis of the femoral head. Methods Polymorphisms of the genes of coagulation factors F7 and F13 were studied; comparative analysis of the frequency of important allelic variants of F7genes (Arg353Gln) and F13 (Val134Leu) in patients with a verified diagnosis of aseptic necrosis (study group) and in healthy patients (control group) was performed. The study group included 41 patients (all males) with aseptic necrosis of the femoral head of unknown etiology. Results The frequency of gene alleles in the F7 Arg353Gln in the study group were: GG in 30 out of 41 patients (73.2 %), GA in 11 out of 41 patients (26.8 %), and none of 41 patients had a polymorphic variant AA. The frequency of alleles of this type of gene in the control group was as follows: GG in 7 out of 320 subjects (2.2 %), GA in 66 out of 320 patients (20.6 %), AA in 247 out of 320 (77.2 %). Significant differences were identified in the frequencies of homozygous genotypes, AA (χ2 = 100.215, p < 0.001) and GG (χ2 = 205.770, p < 0.001) in the study and control groups respectively. As for the heterozygous GA genotype, the differences were not significant (χ2 = 0.834, p = 0.362). The GG genotype of the gene Val134Leu F13 WAS 2.8 times more frequent in patients of the study group, differences were statistically significant (26.8 % against 9.7 %, χ2 = 10.388; p = 0.002). The presence of the TT genotype of the gene Val134Leu F13 was almost five times more frequent (χ2 = 18.956, p < 0.001) in healthy individuals (control group). Differences in the frequency of allele T in homo/ and heterozygous combinations (TT and GT) in the study and control groups was also significant (72.7 % vs 90.1 %, respectively, χ2 = 4.946, p = 0.027). Discussion Polymorphisms of coagulation factors genes F7 and F13 have a significant effect on the genesis of non-traumatic avascular necrosis of the femoral head. Risk factor of ANFH development is homozygous GG genotype in the gene Arg353Gln F7. Low probability of the disease is due to a protective role of AA genotype of the gene Arg353Gln F7 and TT genotype of the gene Val134Leu F13.

Estimating Weights of Evaluation Factors on Basis of Monte Carlo Simulation

2012 ◽  
Vol 268-270 ◽  
pp. 1735-1740
Author(s):  
Yan Fei Tian ◽  
Li Wen Huang
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Random Process ◽  
Stochastic Simulation ◽  
Research Work ◽  
Simulation Method ◽  
Distribution Functions ◽  
Probability Process ◽  
Evaluation Work

Although the value of factor weight in an evaluation work is deterministic, the solving process is random, so connection between weight solution with digital characteristics or distribution functions of specific random variables or random process could be build. Using stochastic simulation method to get a lot of random solutions to the problem, expectation of the random solutions can be used as a estimation solution. On basis of idea of Monte Carlo simulation, this paper analyzed the probability process of calculating factor weight, and provided the procedures of estimating factor weight by means of Monte Carlo simulation. Through discussion and example in this paper, feasibility and validity of this method were proved, which may make foreshadowing for follow-up research work.

scholarly journals Olfactory Dysfunction in β Thalassemia Major Patients Treated With Iron-Chelating Agents

2019 ◽  
Vol 98 (8) ◽  
pp. NP125-NP130
Author(s):  
Serhan Derin ◽  
Selvet Erdogan ◽  
Murat Sahan ◽  
Mehmet Fatih Azik ◽  
Hatice Derin ◽  
...  
Keyword(s):  
Chelating Agents ◽  
Thalassemia Major ◽  
Olfactory Dysfunction ◽  
Facial Trauma ◽  
Control Group ◽  
Control Groups ◽  
History Of ◽  
And Control ◽  
Iron Chelating Agents

Ocular and ophthalmological adverse effects may be seen in β-thalassemia major (BTM) patients treated with regular blood transfusions and iron-chelating agents. We hypothesized that olfactory dysfunction may be present in this population. In this study, we aimed to investigate olfactory dysfunction in patients with BTM and determine the etiological factors. A total of 43 patients with BTM were included in the study. Forty-three patients without any nasal complaints, history of facial trauma, or nasal surgery were included as the controls. All participants had nasal endoscopy. The iron-chelating agents used, their duration of use, as well as hemoglobin and ferritin levels of the BTM patients were recorded. Sniffin’ Sticks test (SST) was used to assess olfactory functions, and BTM and control groups were compared for the results. The correlations of SST scores with the other study parameters were analyzed. Eight (18.6%) of 43 patients in the BTM group had hyposmia while none of the patients in the control group had hyposmia ( P < .001). Older age, low-hemoglobin level, and longer use of deferoxamine were found to be correlated with olfactory dysfunction. Olfactory dysfunction may be seen in BTM patients treated with iron-chelating agents. The results of this study suggest that screening for olfactory function may be needed in routine follow-up of BTM patients.

Monte Carlo simulation of classical swine fever epidemics and control

2005 ◽  
Vol 108 (3-4) ◽  
pp. 199-205 ◽  
Author(s):  
S. Karsten ◽  
G. Rave ◽  
J. Krieter
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Classical Swine Fever ◽  
And Control

Estimating Subgroup Differences in Staffing Research When the Selection Mechanism Is Unknown: A Response to Li’s Case IV Correction

2018 ◽  
Vol 23 (2) ◽  
pp. 367-384 ◽  
Author(s):  
Dustin A. Fife ◽  
Jorge Mendoza ◽  
Eric Day ◽  
Robert Terry
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Group Membership ◽  
Group Differences ◽  
Selection Mechanism ◽  
Range Restriction ◽  
Subgroup Differences ◽  
Cohen’S D ◽  
Selection Decisions ◽  
Cohen's D

When estimating subgroup differences on incumbents, range restriction may bias estimates. Bobko, Roth, and Bobko recognized this problem and developed a Case II and Case III correction for Cohen’s d. Subsequently, Li developed a Case IV correction, which seeks to estimate group differences on a predictor using only incumbent data but must assume that group membership (e.g., ethnicity) plays no role in selection decisions. In this paper, we extend Li’s correction and relax this assumption. In addition, this new correction allows for the estimation of subgroup differences on both the criterion and predictor. Using Monte Carlo simulation, we study the performance of both estimators under situations where Li’s assumptions are violated and demonstrate that this new procedure almost always outperforms Li’s Case IV correction and does so with greater precision. We also provide R code to assist applied researchers in using these corrections.

scholarly journals Time taken to resume driving following hip arthroscopy

2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Suenghwan Jo ◽  
Sang Hong Lee ◽  
Se Woong Jang ◽  
Hyun Bai Choi ◽  
Ba Rom Kim ◽  
...  
Keyword(s):  
Hip Arthroscopy ◽  
Driving Simulator ◽  
Driving Performance ◽  
Control Group ◽  
Control Groups ◽  
Test Protocol ◽  
Surgery Group ◽  
Time Required ◽  
And Control

Abstract Background Resuming driving is a common concern among patients undergoing hip arthroscopy. The present study aimed to assess whether patients who had undergone right hip arthroscopy presented with poorer driving performance than patients with normal hips and to analyze the time required to regain preoperative driving performance. Methods Forty-seven patients who had undergone right hip arthroscopy and consented to our test protocol were included in this study. Using an immersive driving simulator, the patients were tested for their brake reaction time (BRT), total brake time (TBT), and brake pedal depression (BPD) preoperatively and postoperatively. The first postoperative assessments were conducted when the patients could comfortably sit on the driving seat, and the follow-up assessments were conducted for 6 consecutive weeks at weekly intervals. The patients were divided into the following two groups based on the type of surgery that they underwent: the femoroacetabular impingement (FAI) surgery group and the simple hip arthroscopy (SA) group. Twenty healthy volunteers underwent driving assessments thrice at weekly intervals and constituted the control group. The braking parameters were compared between preoperative and postoperative measurements and among the FAI surgery, SA, and control groups. Results The preoperative braking parameters of the patients who underwent arthroscopy did not differ significantly from those of the controls (p = 0.373, 0.763, and 0.447 for the BRT, TBT, and BPD, respectively). All braking parameters returned to normal in 2 weeks in the FAI surgery group and in 1 week in the SA group. Conclusions Our study suggests that the driving performance of patients who underwent right hip arthroscopy is comparable to that of individuals with normal hips and that the braking parameters may normalize to the preoperative state at 1 week after SA and 2 weeks after FAI surgery.

Piano-accompanied solfège reading experiences of preservice music teachers

2020 ◽  
pp. 1321103X1987107
Author(s):  
Elif Guven
Keyword(s):  
Music Teachers ◽  
Control Group ◽  
Reading Practices ◽  
Control Groups ◽  
Plot Analysis ◽  
Experimental Implementation ◽  
Significant Difference ◽  
And Control ◽  
Experimental Group

This study examines how piano-accompanied solfège reading practices of preservice music teachers ( N = 28) affect their performance on their musical hearing, reading, and writing (MHRW) classes. A pretest–posttest design with control groups was employed. The data were analyzed by 2 × 2 split-plot analysis of variance (ANOVA) and one-way ANOVA. Consequently, a significant difference was not found between the MHRW performance scores of the experimental and control groups. An analysis of mean performance scores revealed that the scores received by the control group were higher than those of the experimental group after the practice. Follow-up interviews that were held with 14 students after the experimental implementation revealed that students believed piano-accompanied courses were more useful, and they felt more comfortable with piano accompaniment. Although MHRW performance scores indicated that piano-accompanied solfège reading practices did not have a significant effect on preservice music teachers’ MHRW performances, it helped them participate in courses more enthusiastically.

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