• Title/Summary/Keyword: Variance based sensitivity analysis methods

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Association of coffee consumption with type 2 diabetes and glycemic traits: a Mendelian randomization study

  • Hyun Jeong Cho;Akinkunmi Paul Okekunle ;Ga-Eun Yie ;Jiyoung Youn ;Moonil Kang;Taiyue Jin;Joohon Sung;Jung Eun Lee
    • Nutrition Research and Practice
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    • v.17 no.4
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    • pp.789-802
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    • 2023
  • BACKGROUND/OBJECTIVES: Habitual coffee consumption was inversely associated with type 2 diabetes (T2D) and hyperglycemia in observational studies, but the causality of the association remains uncertain. This study tested a causal association of genetically predicted coffee consumption with T2D using the Mendelian randomization (MR) method. SUBJECTS/METHODS: We used five single-nucleotide polymorphisms (SNPs) as instrumental variables (IVs) associated with habitual coffee consumption in a previous genome-wide association study among Koreans. We analyzed the associations between IVs and T2D, fasting blood glucose (FBG), 2h-postprandial glucose (2h-PG), and glycated haemoglobin (HbA1C) levels. The MR results were further evaluated by standard sensitivity tests for possible pleiotropism. RESULTS: MR analysis revealed that increased genetically predicted coffee consumption was associated with a reduced prevalence of T2D; ORs per one-unit increment of log-transformed cup per day of coffee consumption ranged from 0.75 (0.62-0.90) for the weighted mode-based method to 0.79 (0.62-0.99) for Wald ratio estimator. We also used the inverse-variance-weighted method, weighted median-based method, MR-Egger method, and MR-PRESSO method. Similarly, genetically predicted coffee consumption was inversely associated with FBG and 2h-PG levels but not with HbA1c. Sensitivity measures gave similar results without evidence of pleiotropy. CONCLUSIONS: A genetic predisposition to habitual coffee consumption was inversely associated with T2D prevalence and lower levels of FBG and 2h-PG profiles. Our study warrants further exploration.

Osteoporosis prediction from the mandible using cone-beam computed tomography

  • Barngkgei, Imad;Haffar, Iyad Al;Khattab, Razan
    • Imaging Science in Dentistry
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    • v.44 no.4
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    • pp.263-271
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    • 2014
  • Purpose: This study aimed to evaluate the use of dental cone-beam computed tomography (CBCT) in the diagnosis of osteoporosis among menopausal and postmenopausal women by using only a CBCT viewer program. Materials and Methods: Thirty-eight menopausal and postmenopausal women who underwent dual-energy X-ray absorptiometry (DXA) examination for hip and lumbar vertebrae were scanned using CBCT (field of view: $13cm{\times}15cm;$ voxel size: 0.25 mm). Slices from the body of the mandible as well as the ramus were selected and some CBCT-derived variables, such as radiographic density (RD) as gray values, were calculated as gray values. Pearson's correlation, one-way analysis of variance (ANOVA), and accuracy (sensitivity and specificity) evaluation based on linear and logistic regression were performed to choose the variable that best correlated with the lumbar and femoral neck T-scores. Results: RD of the whole bone area of the mandible was the variable that best correlated with and predicted both the femoral neck and the lumbar vertebrae T-scores; further, Pearson's correlation coefficients were 0.5/0.6 (p value=0.037/0.009). The sensitivity, specificity, and accuracy based on the logistic regression were 50%, 88.9%, and 78.4%, respectively, for the femoral neck, and 46.2%, 91.3%, and 75%, respectively, for the lumbar vertebrae. Conclusion: Lumbar vertebrae and femoral neck osteoporosis can be predicted with high accuracy from the RD value of the body of the mandible by using a CBCT viewer program.

Dental students' ability to detect maxillary sinus abnormalities: A comparison between panoramic radiography and cone-beam computed tomography

  • Rosado, Lucas de Paula Lopes;Barbosa, Izabele Sales;de Aquino, Sibele Nascimento;Junqueira, Rafael Binato;Verner, Francielle Silvestre
    • Imaging Science in Dentistry
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    • v.49 no.3
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    • pp.191-199
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    • 2019
  • Purpose: To compare the diagnostic ability of undergraduate dental students to detect maxillary sinus abnormalities in panoramic radiographs(PR) and cone-beam computed tomography (CBCT). Materials and Methods: This was a retrospective study based on the evaluation of PR and CBCT images. A pilot study was conducted to determine the number of students eligible to participate in the study. The images were evaluated by 2 students, and 280 maxillary sinuses were assessed using the following categories: normal, mucosal thickening, sinus polyp, antral pseudocyst, nonspecific opacification, periostitis, antrolith, and antrolith associated with mucosal thickening. The reference standard was established by the consensus of 2 oral radiologists based on the CBCT images. The kappa test, receiver operating characteristic curves, and 1-way analysis of variance with the Tukey-Kramer post-hoc test were employed. Results: Intraobserver and interobserver reliability showed agreement ranging from substantial (0.809) to almost perfect (0.922). The agreement between the students' evaluations and the reference standard was reasonable (0.258) for PR and substantial(0.692) for CBCT. Comparisons of values of sensitivity, specificity, and accuracy showed that CBCT was significantly better(P<0.05). Conclusion: CBCT was better than PR for the detection of maxillary sinus abnormalities by dental students. However, CBCT should only be requested after a careful analysis of PR by students and more experienced professionals.

Widely-Linear Beamforming and RF Impairment Suppression in Massive Antenna Arrays

  • Hakkarainen, Aki;Werner, Janis;Dandekar, Kapil R.;Valkama, Mikko
    • Journal of Communications and Networks
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    • v.15 no.4
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    • pp.383-397
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    • 2013
  • In this paper, the sensitivity of massive antenna arrays and digital beamforming to radio frequency (RF) chain in-phase quadrature-phase (I/Q) imbalance is studied and analyzed. The analysis shows that massive antenna arrays are increasingly sensitive to such RF chain imperfections, corrupting heavily the radiation pattern and beamforming capabilities. Motivated by this, novel RF-aware digital beamforming methods are then developed for automatically suppressing the unwanted effects of the RF I/Q imbalance without separate calibration loops in all individual receiver branches. More specifically, the paper covers closed-form analysis for signal processing properties as well as the associated radiation and beamforming properties of massive antenna arrays under both systematic and random RF I/Q imbalances. All analysis and derivations in this paper assume ideal signals to be circular. The well-known minimum variance distortionless response (MVDR) beamformer and a widely-linear (WL) extension of it, called WL-MVDR, are analyzed in detail from the RF imperfection perspective, in terms of interference attenuation and beamsteering. The optimum RF-aware WL-MVDR beamforming solution is formulated and shown to efficiently suppress the RF imperfections. Based on the obtained results, the developed solutions and in particular the RF-aware WL-MVDR method can provide efficient beamsteering and interference suppressing characteristics, despite of the imperfections in the RF circuits. This is seen critical especially in the massive antenna array context where the cost-efficiency of individual RF chains is emphasized.

Effects of Personality and Sensory Processing on College Life Adaptation in Students Majoring in Occupational Therapy (작업치료 전공 대학생의 성격과 감각처리가 대학생활 적응에 미치는 영향)

  • Chun-Yeop Lee;Nam-Hae Jung
    • Journal of The Korean Society of Integrative Medicine
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    • v.11 no.4
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    • pp.237-246
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    • 2023
  • Purpose : This study investigated the effects of personality and sensory processing on college life adaptation in students majoring in occupational therapy. Methods : We conducted a survey study on 251 college students from March to May 2023. Personality, sensory processing, and college life adaptation were measured through the international personality item pool, adolescent/adult sensory profile, and student adaptation to college questionnaire, respectively. The general characteristics of students were analyzed using frequency analysis, and differences in college life adaptation and sensory processing characteristics were analyzed using independent t-tests and one-way ANOVA. The relationship between personality, sensory processing, and college life adaptation scores was analyzed using Pearson correlation analysis. The impact of personality and sensory processing on college life adaptation was analyzed using multivariate regression analysis using SPSS 25.0. Results : Correlations of all five personality factors, except openness to experience, were observed with students' college life adaptation. According to sensory processing characteristics, differences in college life adaption showed significant differences in sensory avoidance, poor registration, and sensory sensitivity. The variance of college life adaptation explained by each factor (based on R2) were 46% by personality and 26% by sensory processing. Among personality traits, neuroticism had a negative effect on college life adaptation, agreeableness and extroversion had positive effects, and low registration during sensory processing had a negative effect. Conclusion : This study suggests the provision of various activities and creation of an environment for college students with low sensory registration and neurotic traits to encourage positive changes. The results can be used to design a program that helps college students adapt to occupational therapy majors.

Optimization of Passenger Safety Restraint System for USNCAP by Response Surface Methodology (USNCAP에 대응하는 반응표면법을 이용한 조수석 안전구속장치 최적화)

  • Oh, Eun-Kyung;Lee, Ki-Sun;Son, Chang-Kyu;Kim, Dong-Seok;Chae, Soo-Won
    • Transactions of the Korean Society of Automotive Engineers
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    • v.22 no.6
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    • pp.1-8
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    • 2014
  • Safety performance of a new car is evaluated through USNCAP and their results in the star rating are provided to the consumers. It is very important to obtain high score of USNCAP to appeal their performance to consumers. Therefore the car companies have made the effort to improve their car safety performance. These efforts should satisfy the demand not only to get high score but also to pass the FMVSS, NHTSA regulations on safety. Huge numbers of car crash tests have been conducted on these bases by car companies. However physical tests spend too much cost and time, as an alternative way, the simulation on the car crash could be a solution to reduce the cost and time. Therefore the simulations have been widely conducted in car industry and various researches on this have been reported. In this study, restraint system had been optimized to minimize the injury of female passenger. Belted $5^{th}%ile$ female frontal crash test was selected from various test methods of USNCAP for the study. Initial velocity of the test was 56km/h. The combination injury probability of USNCAP was selected as an objective function and the injury limit value, which was defined in FMVSS, was set to an optimization constraint. Many researches that were similar to this study had been conducted, however most of them had limitation that interaction between airbag and safety belt had not been considered. Contrary to these researches, the interaction was considered in this study.

Potential impact of metal crowns at varying distances from a carious lesion on its detection on cone-beam computed tomography scans with several protocols

  • Matheus Barros-Costa;Eduarda Helena Leandro Nascimento;Iago Filipe Correia-Dantas;Matheus L. Oliveira;Deborah Queiroz Freitas
    • Imaging Science in Dentistry
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    • v.54 no.1
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    • pp.49-56
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    • 2024
  • Purpose: This study evaluated the impact of artifacts generated by metal crowns on the detection of proximal caries lesions in teeth at various distances using cone-beam computed tomography (CBCT). Additionally, the diagnostic impacts of tube current and metal artifact reduction (MAR) were investigated. Materials and Methods: Thirty teeth were arranged within 10 phantoms, each containing 1 first premolar, 1 second premolar, and 1 second molar. A sound first molar (for the control group) or a tooth with a metal crown was placed. Of the 60 proximal surfaces evaluated, 15 were sound and 45 exhibited enamel caries. CBCT scans were acquired using an OP300 Maxio unit (Instrumentarium, Tuusula, Finland), while varying the tube current (4, 8, or 12.5 mA) and enabling or disabling MAR. Five observers assessed mesial and distal surfaces using a 5-point scale. Multi-way analysis of variance was employed for data comparison, with P<0.05 indicating statistical significance. Results: The area under the curve (AUC) varied from 0.40 to 0.60 (sensitivity: 0.28-0.45, specificity: 0.44-0.80). The diagnostic accuracy was not significantly affected by the presence of a metal crown, milliamperage, or MAR(P>0.05). However, the overall AUC and specificity were significantly lower for surfaces near a crown (P<0.05). Conclusion: CBCT-based caries detection was not influenced by the presence of a metal crown, variations in milliamperage, or MAR activation. However, the diagnostic accuracy was low and was further diminished for surfaces near a crown. Consequently, CBCT is not recommended for the detection of incipient caries lesions.

Evaluation of Health-related Quality of Life for Hypothesized Medical States Associated with Cervical Cancer

  • Murasawa, Hideki;Konno, Ryo;Okubo, Ichiro;Arakawa, Ichiro
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.22
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    • pp.9679-9685
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    • 2014
  • Background: When evaluating health-economics for cervical cancer prevention policies in Japan, it is important to use Japanese value settings. This study aimed to obtain preference-based measures (preference measures) for hypothesized health states among healthy Japanese women, and to examine differences between the EuroQol-5D (EQ-5D) and standard gamble (SG) instruments. Materials and Methods: The investigation was performed among female students at a nursing university. We used written hypothetical scenarios describing three grades of cervical intraepithelial neoplasia (CIN) and eight stages of cervical cancer, both at diagnosis and after medical intervention. Preference measures were evaluated using both EQ-5D and SG. Results: We received responses from 136 women. The mean number of respondents per stage was 24.6 (SD: 2.7). At diagnosis, average EQ-5D scores for CIN1, CIN2, CIN3, IA1, IA2, IB1, IB2, IIA, IIB, III, and IV stages were 0.84 (0.14), 0.78 (0.12), 0.73 (0.10), 0.78 (0.12), 0.72 (0.12), 0.63 (0.13), 0.64 (0.12), 0.68 (0.08), 0.62 (0.13), 0.55 (0.21), and 0.18 (0.24), respectively. Using one-way analysis of variance with the Tukey-Kramer method for multiple comparisons (each stage vs. CIN1), we found significant differences for IB1 and more advanced stages (p<0.05). After medical intervention, corresponding EQ-5D scores were 0.84 (0.12), 0.81 (0.12), 0.84 (0.12), 0.80 (0.15), 0.78 (0.11), 0.64 (0.15), 0.63 (0.15), 0.71 (0.15), 0.50 (0.17), 0.52 (0.17), 0.21 (0.28). The multiple comparisons identified significant differences for IB1 and more advanced stages, excepting IIA (p<0.05). SG evaluations were more variable and relatively higher than EQ-5D evaluations. Conclusions: We obtained preference measures for three grades of CIN1-3 and eight stages of cervical cancer. In combination with appropriate sensitivity analyses, these preference measures will provide a basis for an economic evaluation of cervical cancer prevention in Japan. We suggest that EQ-5D is appropriate for cost-utility analysis of this topic.

The Effect of Internalized Shame and Self-Control on Interpersonal Relationships in Stroke Patients (내면화된 수치심과 자기통제력이 뇌졸중 환자의 대인관계에 미치는 영향)

  • Hwang, Jung-Ha;Lim, Jae-Ho
    • The Journal of Korean society of community based occupational therapy
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    • v.10 no.3
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    • pp.63-74
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    • 2020
  • Objective : The purpose of this study is to investigate the influence of internal shame and self-control on interpersonal relationships in stroke patients, and to provide evidence and information necessary for clinical trials by analyzing the relationship. Methods : For this study, 150 stroke patients receiving occupational therapy services at institutions where occupational therapists work in Jeollanam-do and Chungnam regions were targeted through email and mail from March 1, 2019 to April 30, 2019. The questionnaire was conducted using general characteristics, Relationship Change Scales(RCS), Self-Control Scales(SCS), and Internalized Shame Scale(ISS) questionnaire. Descriptive statistical analysis was performed for the general characteristics of the study subjects, and t-test and one-way batch variance analysis (ANOVA) were used to compare interpersonal relationships according to general characteristics. The relationship between internalized shame, self-control, and interpersonal competence was analyzed by Pearson's correlation coefficient, and multiple regression analysis was performed to determine the factors affecting interpersonal relationships of stroke patients. Results : As a result of comparing interpersonal competence according to general characteristics, significant differences were found in terms of age and education level. Interpersonal relationships and internalized shame, internalized shame and self-control showed a negative correlation, and self-control and interpersonal relationships had a positive correlation, but self-control was the sub-factors of interpersonal relationships such as openness, sensitivity, intimacy, It was not statistically significant with the communication item. In addition, the items of inadequacy (β =-0.32) and adventure seeking (β =-0.23), which are sub-areas of internalized shame, affect the negative direction, and physical activity (β =0.22), which is the sub-area of self-control and the self-centered (β =0.24) item was found to have an effect on the positive direction. Conclusion : Therefore, additional research is needed that can operate a rehabilitation treatment program that applies various psychological factors for the formation of interpersonal relationships among stroke patients.

The Validation Study of Beck Depression Scale 2 in Korean Version (한국판 벡 우울 척도 2판의 타당화 연구)

  • Lim, Sun-Young;Lee, Eun-Jeong;Jeong, Seong-Won;Kim, Hee-Chul;Jeong, Cheol-Ho;Jeon, Tae-Yeon;Yi, Min-Soo;Kim, Jae-Min;Jo, Hyeon-Ju;Kim, Jeong-Beom
    • Anxiety and mood
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    • v.7 no.1
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    • pp.48-53
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    • 2011
  • Objective : Korean Version of Beck-II Depression Inventory to verify the reliability and validity of the proposed standards are practical and standardized, cut-off score by establishing a baseline indicating the presence of depression and depression On in the evaluation was to evaluate the clinical usefulness. Methods : 739 patients with major depression using the SCID and normal controls were 302 study subjects. Of patients with clinically significant medical condition, or psychotic disorders, organic mental disorder, epilepsy or seizure disorder, eating disorders are associated with patients taking anti-convulsants experienced in the past, patients were excluded from the study. Results : The main findings of this study were as follows. First, with respect to the KBDI-II items, the correlation between them ranged from 0.51 to 0.74, and was 0.60 over all questions. Further, the overall correlation of the KBDI-II plates showing confidence 'normal' than it was verified that. Second, the BDIII was used in each group to examine internal consistency and thus, whether Cronbach's alpha values were greater than 0.94. Third, the principal component analysis sought to extract factors in a way consistent with the results inspected last 3 factors were extracted and the total variance explained was 47.3%. Fourth, the Cutting calculated the score on the KBDI-II for ROC (Receiver operator characteristic) analysis yielding 18 dot, with the highest sensitivity and specificity was seen. Conclusion : Based on the results of this Study, the KBDI-II cut-off point should be valid as prescribed in 18 is considered.