Principles of Radiographic Imaging: An Art and a Science

The COVID-19 pandemic has seen an unmatched level of panic buying globally, a type of herd behavior whereby consumers buy an uncommonly huge amount of products because of a perception of scarcity. Drawing on the health belief model, perceived scarcity, and anticipated regret theories, this paper formulated a theoretical model that linked the determinants of panic buying and analyzed their interrelationships. Subsequently, data were collated from 508 consumers through an online survey questionnaire in Singapore that was conducted during the early stage of the pandemic, before the onset of the circuit breaker in April 2020. Next, an analysis of the results was done through structural equation modeling. It showed that the effect of the health belief model dimensions (i.e., perceived susceptibility, perceived severity, outcome expectation, cues to action, and self-efficacy) on panic buying is partially mediated by the consumers' perceived scarcity of products. Furthermore, the effect of perceived scarcity on panic buying is partially mediated by consumers' anticipation of regret. This paper expands on the current theoretical understanding of panic buying behavior, giving insights into the possible measures and solutions that policymakers and relevant stakeholders can uptake to manage panic buying in future a pandemic or health crisis.

The Determinants of Panic Buying during COVID-19.

Handbook of nutrition, diet and the eye

Background: Particularly during the early and middle stages of the COVID-19 pandemic, a population's compliance with precautionary measures (e.g., hygiene rules, smart working, travel restrictions, and quarantine) is paramount in preventing the virus from spreading. Objective: The investigation and documentation of different socio-demographic and personality-specific factors in regards to preventative measures and consequent specific health behaviors during the COVID-19 pandemic, based on the Health Belief Model. Method: An online survey was conducted on N = 3,006 individuals living in Germany and Austria during the early stages of lockdown. The questionnaire consisted of a self-administered section, exploring the dimensions posited in the Health Belief Model: perceived severity, perceived susceptibility, perceived barriers, perceived benefits of health-promoting measures, and engagement in health-promoting behaviors. Additionally, the following standardized scales were used to record personality determinants: the Stress Coping Style Questionnaire SVF 78 to evaluate coping and processing strategies in stressful circumstances, the Positive and Negative Affect Schedule (PANAS) to assess the emotional state induced by the coronavirus crisis, the UI-18 scale to diagnose the intolerance of uncertainty, and the State-Trait Anxiety Inventory (STAI) to assess anxiety. Results: In line with the Health Belief model, four groups were created based on perceived susceptibility and engagement in health-promoting behaviors, and consequently studied in relation to personality determinants. Those four groups differed significantly in regards to almost all personality dimensions (p ≤ 0.005). Group 1 (n = 450) shows a reduced engagement with protective measures and displays underestimation of the COVID-19-pandemic. Group 2 (n = 984) displays many positive personality variables and high compliance with protective measures. Group 3 (n = 468) perceives the subjective risk of disease as high, but high emotional discomfort and stress caused by the protective measures leads to the activation of a complex fear defense. Group 4 (n = 1,004) is highly anxious and therefore compliant. Conclusion: This typification has implications for establishing the appropriate support systems. This is particularly important to encourage compliance with preventive regulations within the groups, which showed poor abidance for several reasons. For Group 1, further education on the realistic threat and efficient protective measures is as central as the fostering of empathy for others; with its resource-conscious exemplary behavior Group 2 could be used as a positive social role model. Group 3 would benefit from promoting self-care, while Group 4 requires information on psychosocial assistance availability in order to mitigate the high stress to which the group members are subjected.

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The Relationship Between the Implementation of Statutory Preventative Measures, Perceived Susceptibility of COVID-19, and Personality Traits in the Initial Stage of Corona-Related Lockdown: A German and Austrian Population Online Survey

Background: Mammography screening uptake is the most effective method in breast cancer screening. The aim of this study was to determine the determinants related to mammography screening uptake among Iranian women based on the theory of planned behavior. Materials and Methods: This cross-sectional study was conducted among 408 women who referred to health centers in Kermanshah city, the western of Iran, during 2016. Participants filled out a self-administered questionnaire. Data were analyzed by SPSS version 21 using Pearson correlation, linear and logistic regression statistical tests at 95% significant level. Results: The mean age of participants was 39.61 years [SD: 8.28], ranged from 30 to 60 years. Almost 13% of the participants had already mammography screening uptake at least once. Perceived behavioral control (OR=1.229) and behavioral intention (OR=1.283) were the more influential predictors on mammography screening uptake. Conclusions: Based on result, it seems increase perceived behavior control toward mammography screening uptake may be usefulness in promotion of mammography screening uptake among Iranian women.

http://journal.waocp.org/article_59597_5c82bf1f11dae33a08179673bd6c13c3.pdf

Socio-Cognitive Determinants of the Mammography Screening Uptake among Iranian Women

Background: Early detection of breast cancer is essential in improving overall women’s health. The researchers sought to develop a comprehensive measure that combined the basic components of the health belief model (HBM) with a focus on breast self-examination (BSE) and screening mammogram amongst women. Methods: Questionnaire items were developed following a review of relevant literature of HBM on BSE and screening mammogram. The sampling frame for the study was Malaysian women aged 35 to 70 years old, living in Kuantan, Pahang and able to read or write in Bahasa Malaysia or English. As such, 103 women were randomly selected to participate in the study. Tests of validity using exploratory factor analysis (EFA) and reliability were subsequently performed to determine the psychometric properties of the questionnaire. Results: The EFA revealed nine factors (self-efficacy of mammogram, perceived barriers of BSE and mammogram, perceived susceptibility of breast cancer, perceived severity of breast cancer, cues to action for mammogram screening, perceived benefits of BSE, health motivation, perceived benefits of mammogram and self-efficacy of BSE) containing 54 items that jointly accounted for 74.2% of the observed variance. All nine factors have good internal consistency with Cronbach’s alpha ≥ 0.8. Fifty-four items remained in the final questionnaire after deleting 13 problematic items. The scale also showed good convergent and discriminant validity. Conclusion: The findings showed that the designed questionnaire was a valid and reliable instrument for the study involving women in Kuantan, Pahang. The instrument can help to assess women’s beliefs on BSE adoption and mammogram screening in health care practice and research.

http://journal.waocp.org/article_88749_6ea64228e24477de8e268e97c93d7d4c.pdf

Validity and Reliability of Health Belief Model Questionnaire for Promoting Breast Self-examination and Screening Mammogram for Early Cancer Detection.

IntroductionA fine balance of image quality and radiation dose can be achieved by optimization to minimize stochastic and deterministic effects. This study aimed in ensuring that images of acceptable quality for common radiographic examinations in digital imaging were produced without causing harmful effects. Materials and MethodsThe study was conducted in three phases. The pre-optimization involved ninety physically abled patients aged between 20 to 60 years and weighed between 60 and 80 kilograms for four common digital radiographic examinations. Kerma X_plus, DAP meter was utilized to measure the entrance surface dose (ESD) while effective dose (ED) was estimated using CALDose_X 5.0 Monte Carlo software. The second phase, an experimental study utilized an anthropomorphic phantom (PBU-50) and Leeds test object TOR CDR for relative comparison of image quality. For the optimization phase, the imaging parameters with acceptable image quality and lowest ESD from the experimental study was related to patient’s body thickness. Image quality were evaluated by two radiologists using the modified evaluation criteria score lists. ResultsSignificant differences were found for image quality for all examinations. However significant difference for ESD were found for PA chest and AP abdomen only. The ESD for three of the examinations were lower than all published data. Additionally, the ESD and ED obtained for all examinations were lower than that recommended by radiation regulatory bodies. ConclusionOptimization of image quality and dose was achieved by utilizing an appropriate tube potential, calibrated automatic exposure control and additional filtration of 0.2mm copper.

http://ijmp.mums.ac.ir/article_9546_14a4845c6be4ffd83b1a2c4a21dc3d2f.pdf

Optimization of Dose and Image Quality in Full-fiand Computed Radiography Systems for Common Digital Radiographic Examinations

Introduction: The purpose of this study is to investigate the effects of grid and non-grid techniques in the lateral cervical spine radiography on image quality and entrance surface dose (ESD). Although image quality and radiation doses have been studied by researchers, there is still a dearth of information on image quality and patient dose with different techniques. Material and Methods: The radiographs of the lateral cervical spine were acquired by positioning the RANDO phantom abutting the erect bucky while using the grid and non-grid techniques. This study benefited from using a 24 cm x 30 cm Fuji standard cassette type imaging plate. A Leeds TOR test tool was utilized for relative comparison of image quality. The ESD of each examination was determined by using the optically stimulated luminescence dosimeter. Results: The increased kilovoltage (kVp) resulted in the reduction of ESD whether moving grid, stationary grid, or non-grid techniques were utilized. Significant differences in terms of contrast sensitivity and spatial resolution were indicated when comparing the grid technique to that of the non-grid technique (i.e., χ2=8 and 5, 16 respectively, p ). The results also indicated significant differences in ESD when using the moving grid, stationary grid, and non-grid techniques (i.e., χ2=7.2, 16p ). Conclusion: Significant differences in image quality and ESD were indicated when grid and non-grid techniques were used in the lateral cervical spine radiography. A non-grid with the highest appropriate kVp is recommended as the air gap acts as a grid, resulting in acceptable image quality with reduction in ESD.

http://ijmp.mums.ac.ir/article_11298_ab1511f31157068abec29ee39c1de828.pdf

Image Quality and Entrance Surface Dose Evaluation of Lateral Cervical Spine: A Study Using Grid and Non-Grid Techniques

Introduction: In digital radiography, radiographers tend to increase exposure factors to acquire an acceptable image quality thereby increasing radiation dose to patients.  Regarding this, the present study aimed to re-evaluate the exposure parameters and to ascertain the entrance surface dose (ESD) and effective dose (ED) of posterior-anterior (PA) chest, abdomen, and anterior-posterior (AP) lumbosacral spine radiography.
Materials and Methods: This study was conducted on 180 physically able patients with age of 20-60 years and weight of 60-80 kg referred to Hospital Sultan Haji Ahmad Shah (HOSHAS) and Hospital Tengku Ampuan Afzan (HTAA).Image acquisition was performed using digital radiography. The ESD and ED were determined using CALDose_X 5.0 software.
Results: The ESD and ED for PA chest were 0.098 mGy and 0.012 mSv in HOSHAS, while in HTAA were 0.161 mGy and 0.021 mSv respectively. Regarding the abdomen, the ESD and ED were 2.57 mGy and 0.311 mSv in HOSHAS and 2.16 mGy and 0.262 mSv in HTAA respectively. For AP lumbosacral spine, the ESD and ED for HOSHAS were 2.65 mGy and 0.222 mSv, while in HTAA were 2.357 mGy and 0.201 mSv respectively. 
Conclusion: The findings revealed the use of high kVp, automatic exposure control, correct focus image receptor distance, tight collimation and additional filter resulted in a lower ESD. The ESD and ED obtained in this study were comparable with those reported by other studies and lower than the values recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation in 2008.

http://ijmp.mums.ac.ir/article_8835_e62fb201582efe42733fd9b00eb1b147.pdf

Dose Evaluation for Common Digital Radiographic Examinations in Selected Hospitals in Pahang Malaysia

Introduction: The study was undertaken to evaluate the practice of chest radiography using different digital imaging systems and its influence on dose and image quality.
 Materials and Methods: The study was carried out in two hospitals from March 2016 to June 2016. Sixty ambulatory patients aged 21 to 60 years who were able to cooperate without difficulty and weighed between 60 to 80 kg were selected randomly. The active matrix flat panel imagers technology was employed in the direct radiography (DR) system for Hospital A, whilst Hospital B used the single read out computed radiography (CR) system. The dose area product (DAP) meter was utilized in measuring the entrance surface air kerma. The chest radiographs were evaluated by two radiologists.
 Results: The mean entrance surface doses (ESDs) for posteroanterior chest in Hospital A (0.098 mGy) was lower than that obtained in Hospital B (0.161 mGy). However, the ESDs at both centres were lower than the recommended value by the International Atomic Energy Agency (IAEA; 0.3 mGy). The quality of the images for chest radiography in both hospitals was adequate to make a diagnosis with ESDs and effective doses lower than those recommended by IAEA and United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR).
 Conclusion: The study serves to highlight the practice of chest radiography with two different systems and its influence on image quality and dose. It can be concluded that there were significant differences in image quality and radiation dose for chest radiography practice using CR and DR.

http://ijmp.mums.ac.ir/article_9583_f66007092045e54a4aaa22ed177ad168.pdf

Soo Foon Moey

Papers

Validity and Reliability of Health Belief Model Questionnaire for Promoting Breast Self-examination and Screening Mammogram for Early Cancer Detection.

Optimization of Dose and Image Quality in Full-fiand Computed Radiography Systems for Common Digital Radiographic Examinations

Image Quality and Entrance Surface Dose Evaluation of Lateral Cervical Spine: A Study Using Grid and Non-Grid Techniques

Dose Evaluation for Common Digital Radiographic Examinations in Selected Hospitals in Pahang Malaysia

The Practice of Chest Radiography Using Different Digital Imaging Systems: Dose and Image Quality