In optical coherence tomography angiography, the choroidal vascular flow rate in choroidal melano... more In optical coherence tomography angiography, the choroidal vascular flow rate in choroidal melanoma is significantly lower than that in choroidal nevus. Objective: The objective of this study was to describe the choriocapillaris and retinal features imaged by optical coherence tomography angiography (OCTA) in eyes with choroidal nevus from small malignant choroidal melanoma. Methods: In this retrospective, noninvasive, observational study, 11 patients diagnosed with small choroidal mass (five with choroidal nevus and six with malignant melanoma) who underwent dilated fundus examination, ocular ultrasonography and OCTA images were compared. Results: In choroidal nevus of all patients, OCTA demonstrated a hyporeflective mass with no significant deformity of choroidal vasculature and an intact retinal pigment epithelium (RPE)-Bruch's membrane complex. The flow void mass was surrounded by an intense vascular rim named as surface microvasculature (SMV) that had an approximately similar flow rate median of 63.68 mm 2 (60.42-67.62 mm 2 ), comparable with the median of the contralateral normal eye of 61.77 mm 2 (60.42-64.53 mm 2 ; P.0.09) for nevi. OCTA showed an obscured Bruch's membrane-RPE-Bruch's membrane complex and outer retinal layer in choroidal melanomas. Choriocapillaris flow rate over the melanomas was 55.73% (41.93%-60.82%), and the corresponding normal areas had a flow area of 62.75% (61.99%-63.10%; P=0.01). A flow rate difference between choroidal melanoma and nevus was significant (P=0.006). Axial and peripheral feeding vessels were more dilated and tortuous compared with benign nevi. Conclusion: Decreased flow rate of SMV of choroidal melanoma cases compared with nevi was a significant finding. Detection of characteristic vascular features of choroidal melanoma by OCTA could make OCTA an assuring diagnostic modality to differentiate malignant lesions.
Our study aimed to assess the accuracy of dietary flavonol (quercetin, kaempferol, and isorhamnet... more Our study aimed to assess the accuracy of dietary flavonol (quercetin, kaempferol, and isorhamnetin) intake from a food frequency questionnaire (FFQ) compared to fasting plasma flavonol concentrations, as biomarkers of exposure, in breast cancer patients. In a consecutive case series, newly diagnosed patients with breast cancer (n=140) were recruited at Nour-Nejat Hospital, Tabriz, Iran. Flavonol intake was assessed using a validated FFQ. Plasma flavonol levels were measured using high-performance liquid chromatography-ultraviolet detector. The accuracy of dietary status was evaluated using a receiver operating characteristic (ROC) and area under the ROC curve (AUC). Dietary status was shown in dichotomous using ROC-cutoff point. The plasma concentrations of quercetin were moderately correlated with dietary intake of quercetin (Spearman's correlation coefficient (rs) =0.188, P<0.05; rpartial=0.330, P<0.01) and plasma concentrations of isorhamnetin (rs =0.337, P<0.001). A linear correlation between dietary levels and plasma concentrations of kaempferol was attained (rpartial=0.240, P<0.05). Using a ROC-cutoff of 61.9 nmol/L for plasma quercetin (test reference), we were able to differentiate between lower and higher consumers of quercetin with an AUCROC-based reference =0.65 (P<0.01, sensitivity=61.8%, and specificity=60.0%). Using a plasma kaempferol level of 60.1 nmol/L (ROC-cutoff), it was possible to detect significant differences between higher and lower intakes of kaempferol (AUCROCbased reference = 0.64, P<0.05). The correlations and diagnostic performance with plasma concentrations could present a significant accuracy rate (validity), which seems acceptable for a nutritional questionnaire (FFQ) to assess quercetin and kaempferol. An improvement in the classification accuracy of flavonol exposure can provide more precise chemopreventive effects of flavonols in humans, increasing their clinical significance.
Background: Job stress is uncomfortable feeling toward anything that increase physical and mental... more Background: Job stress is uncomfortable feeling toward anything that increase physical and mental tension to the nurses. Coping is the process of spending conscious effort and energy to solve personal and interpersonal problems. Aim: (This study aimed to assess job stress and coping among nurses caring leukemic children at 57357hospital). Subjects and Methods: This study was descriptive research design, A convenient sample was selected while this study was performed on 100 psychiatric nurses working at 57357 hospital and data were collected through using tools 1) Socio-demographic sheet, 2) Stress index Scale and 3) coping inventory scale Results: The main results showed that nurses suffered from a different aspects of stress regarding psychiatric nurses ability, the attitude of patient, attitude to nursing and communication with children. And, the result indicated that mostly of nurses were have low coping level toward stress. Furthermore, There was a statistically significant relation between stress, coping and socio demographic data of nurses under study. Conclusions: the study concluded that nurses working at 57357hospital had job stress and low coping level. Recommendations: This study recommended that, Establish a psycho educational Program for 57357 nurses under study to learn them how to cope positively with their stressors. Training programs and courses would help the 57357 nurse to enhance their stress bearing capacity and also improve their work performance.
We were interested to read the article by Laskiewicz et al that was recently published in Cancer ... more We were interested to read the article by Laskiewicz et al that was recently published in Cancer Cytopathology. Due to the controversy regarding the accuracy of grading pancreatic neuroendocrine tumors (PNETs) on fine-needle aspiration (FNA) biopsy, the authors' objective was to evaluate whether grading according to the percentage of Ki-67-positive tumor cells (the Ki-67 proliferation index) on material from endoscopic ultrasound-guided FNA biopsies correlated with grading on surgical resection specimens. A case series of 27 PNETs with FNA biopsies and corresponding surgical resection specimens from the authors' institution were evaluated. 1 Based on their results, a correct FNA diagnosis with the ability to distinguish between grade 1 and grade 2 tumors had a positive predictive value of 88.9%, with a sensitivity of 72.7% and a specificity of 93.3%. Diagnostic value can be considered as diagnostic accuracy (validity) and diagnostic precision (reliability). To assess validity for qualitative variables, sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio as well as diagnostic accuracy and the odds ratio (ratio of true results to false results) are among the most appropriate tests. It is good to know that we should consider all of the above-mentioned validity estimates when judging the accuracy of that test. Moreover, for clinical purposes, it is crucial to know that reporting the diagnostic added value of a diagnostic test using the receiver operating characteristic curve should be considered. 2 Reliability (precision) as a different methodological issue of diagnostic value also should be assessed using appropriate tests. Without assessing the reliability of a diagnostic test, we should not judge the diagnostic value because a test can be acceptably accurate with no reliability. For qualitative variables, weighted kappa can be applied. Laskiewicz et al concluded that the grading of PNETs on FNA using the Ki-67 proliferation index should be assessed and is a practical parameter to report to clinicians. 1 Such a conclusion should be supported by the above methodological and statistical issues. Otherwise, in clinical practice, mismanagement of patients may occur.
Any decision in clinical practice needs to evaluate both reliability (precision) and validity (ac... more Any decision in clinical practice needs to evaluate both reliability (precision) and validity (accuracy) of a diagnostic test. Without knowledge about the reliability, any judgment would be wrong. In diagnostic accuracy research, it is essential to evaluate the diagnostic added value of a test, since a diagnostic accuracy of a single test might be excellent, however for clinical purposes it can be worthless. Like evaluating discrimination, it would be possible to estimate the diagnostic added value by applying ROC of diagnostic model with and without test results in the model.
In this letter, I discussed important limitations of applying kappa statistics to assess agreemen... more In this letter, I discussed important limitations of applying kappa statistics to assess agreement. Any conclusion in agreement needs to be supported by the methodological and statistical issues mentioned previously. Otherwise, misinterpretation cannot be avoided.
Journal of Nuclear Medicine Technology, Dec 6, 2019
Self-Reported Weight and Height in Nuclear Medicine Patients: A Common Mistake Confusing Reliabil... more Self-Reported Weight and Height in Nuclear Medicine Patients: A Common Mistake Confusing Reliability and Accuracy TO THE EDITOR: I read with great interest the article by Blum et al. recently published in the Journal of Nuclear Medicine Technology (1). The authors aimed to assess the reliability of the selfreported weight and height of nuclear medicine patients in view of recommendations for weight-dependent tracer application for imaging and therapy. In total, 824 patients (334 men and 490 women) were asked to report their weight and height before imaging or therapy, along with their level of confidence that the weight and height they were reporting were correct. Subsequently, the weight and height of each patient were measured, and body mass index, body surface area, and lean body mass were calculated. Differences between the reported and true values were compared for statistical significance. The results indicated that an over-or underestimation of weight by at least 10% was observed in 2% of the patients, and height was overestimated by 1% of the patients. Surprisingly, the authors concluded that most self-reported weights and heights of nuclear medicine patients are accurate. However, there were some methodologic issues regarding accuracy and reliability. First, it is crucial to realize that accuracy and reliability are two completely different methodologic issues. The term accuracy means the degree to which the result of a measurement, calculation, or specification conforms to the correct value or a standard. In other words, accuracy is the most important criterion for the quality of a test and refers to whether the test measures what it claims to measure. The core design for determining and measuring the accuracy of a test is a comparison between an index test and a reference standard by applying both on similar people who are suspected of having the target result of interest. The term reliability denotes refinement of a measurement, calculation, or specification, especially as represented by the number of digits given. Accuracy studies should report significant and comprehensive information together with the absolute number of true-positive, false-positive, false-negative, and true-negative results or should provide information that allows calculation of a minimum of one diagnostic performance indicator (i.e., sensitivity, specificity, predictive values, or likelihood ratio). Therefore, we recommend applying the most appropriate estimates to evaluate the accuracy of the self-reported weight and height. The Pearson r or the Spearman r can be applied to assess accuracy for quantitative variables. However, for qualitative (binary) variables, some of the well-known ways to assess accuracy include sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio (ranging from 1 to infinity; the higher the positive likelihood ratio, the more accurate the test), negative likelihood ratio (ranging from 0 to 1; the lower the negative likelihood ratio, the more accurate the test), diagnostic accuracy, and odds ratio (ratio of true results to false results) (2-8). Is There a Need for a Pediatric PET/CT Camera? TO THE EDITOR: PET imaging is commonly used in adult patients. Its use in pediatric patients is limited but indicated in certain cancers such as lymphoma, sarcoma, neuroblastoma, and central nervous system tumors (1). The main limitation of PET imaging is its relatively limited spatial resolution in detecting small lesions, mainly because of the noncollinearity of the 511-keV annihilation photons, positron range, detector scatter, and parallax error (2-5). However, small-animal PET scanners have higher spatial resolution than standard human PET scanners (approximately 1 mm vs. 4-6 mm)
In optical coherence tomography angiography, the choroidal vascular flow rate in choroidal melano... more In optical coherence tomography angiography, the choroidal vascular flow rate in choroidal melanoma is significantly lower than that in choroidal nevus. Objective: The objective of this study was to describe the choriocapillaris and retinal features imaged by optical coherence tomography angiography (OCTA) in eyes with choroidal nevus from small malignant choroidal melanoma. Methods: In this retrospective, noninvasive, observational study, 11 patients diagnosed with small choroidal mass (five with choroidal nevus and six with malignant melanoma) who underwent dilated fundus examination, ocular ultrasonography and OCTA images were compared. Results: In choroidal nevus of all patients, OCTA demonstrated a hyporeflective mass with no significant deformity of choroidal vasculature and an intact retinal pigment epithelium (RPE)-Bruch's membrane complex. The flow void mass was surrounded by an intense vascular rim named as surface microvasculature (SMV) that had an approximately similar flow rate median of 63.68 mm 2 (60.42-67.62 mm 2 ), comparable with the median of the contralateral normal eye of 61.77 mm 2 (60.42-64.53 mm 2 ; P.0.09) for nevi. OCTA showed an obscured Bruch's membrane-RPE-Bruch's membrane complex and outer retinal layer in choroidal melanomas. Choriocapillaris flow rate over the melanomas was 55.73% (41.93%-60.82%), and the corresponding normal areas had a flow area of 62.75% (61.99%-63.10%; P=0.01). A flow rate difference between choroidal melanoma and nevus was significant (P=0.006). Axial and peripheral feeding vessels were more dilated and tortuous compared with benign nevi. Conclusion: Decreased flow rate of SMV of choroidal melanoma cases compared with nevi was a significant finding. Detection of characteristic vascular features of choroidal melanoma by OCTA could make OCTA an assuring diagnostic modality to differentiate malignant lesions.
Our study aimed to assess the accuracy of dietary flavonol (quercetin, kaempferol, and isorhamnet... more Our study aimed to assess the accuracy of dietary flavonol (quercetin, kaempferol, and isorhamnetin) intake from a food frequency questionnaire (FFQ) compared to fasting plasma flavonol concentrations, as biomarkers of exposure, in breast cancer patients. In a consecutive case series, newly diagnosed patients with breast cancer (n=140) were recruited at Nour-Nejat Hospital, Tabriz, Iran. Flavonol intake was assessed using a validated FFQ. Plasma flavonol levels were measured using high-performance liquid chromatography-ultraviolet detector. The accuracy of dietary status was evaluated using a receiver operating characteristic (ROC) and area under the ROC curve (AUC). Dietary status was shown in dichotomous using ROC-cutoff point. The plasma concentrations of quercetin were moderately correlated with dietary intake of quercetin (Spearman's correlation coefficient (rs) =0.188, P<0.05; rpartial=0.330, P<0.01) and plasma concentrations of isorhamnetin (rs =0.337, P<0.001). A linear correlation between dietary levels and plasma concentrations of kaempferol was attained (rpartial=0.240, P<0.05). Using a ROC-cutoff of 61.9 nmol/L for plasma quercetin (test reference), we were able to differentiate between lower and higher consumers of quercetin with an AUCROC-based reference =0.65 (P<0.01, sensitivity=61.8%, and specificity=60.0%). Using a plasma kaempferol level of 60.1 nmol/L (ROC-cutoff), it was possible to detect significant differences between higher and lower intakes of kaempferol (AUCROCbased reference = 0.64, P<0.05). The correlations and diagnostic performance with plasma concentrations could present a significant accuracy rate (validity), which seems acceptable for a nutritional questionnaire (FFQ) to assess quercetin and kaempferol. An improvement in the classification accuracy of flavonol exposure can provide more precise chemopreventive effects of flavonols in humans, increasing their clinical significance.
Background: Job stress is uncomfortable feeling toward anything that increase physical and mental... more Background: Job stress is uncomfortable feeling toward anything that increase physical and mental tension to the nurses. Coping is the process of spending conscious effort and energy to solve personal and interpersonal problems. Aim: (This study aimed to assess job stress and coping among nurses caring leukemic children at 57357hospital). Subjects and Methods: This study was descriptive research design, A convenient sample was selected while this study was performed on 100 psychiatric nurses working at 57357 hospital and data were collected through using tools 1) Socio-demographic sheet, 2) Stress index Scale and 3) coping inventory scale Results: The main results showed that nurses suffered from a different aspects of stress regarding psychiatric nurses ability, the attitude of patient, attitude to nursing and communication with children. And, the result indicated that mostly of nurses were have low coping level toward stress. Furthermore, There was a statistically significant relation between stress, coping and socio demographic data of nurses under study. Conclusions: the study concluded that nurses working at 57357hospital had job stress and low coping level. Recommendations: This study recommended that, Establish a psycho educational Program for 57357 nurses under study to learn them how to cope positively with their stressors. Training programs and courses would help the 57357 nurse to enhance their stress bearing capacity and also improve their work performance.
We were interested to read the article by Laskiewicz et al that was recently published in Cancer ... more We were interested to read the article by Laskiewicz et al that was recently published in Cancer Cytopathology. Due to the controversy regarding the accuracy of grading pancreatic neuroendocrine tumors (PNETs) on fine-needle aspiration (FNA) biopsy, the authors' objective was to evaluate whether grading according to the percentage of Ki-67-positive tumor cells (the Ki-67 proliferation index) on material from endoscopic ultrasound-guided FNA biopsies correlated with grading on surgical resection specimens. A case series of 27 PNETs with FNA biopsies and corresponding surgical resection specimens from the authors' institution were evaluated. 1 Based on their results, a correct FNA diagnosis with the ability to distinguish between grade 1 and grade 2 tumors had a positive predictive value of 88.9%, with a sensitivity of 72.7% and a specificity of 93.3%. Diagnostic value can be considered as diagnostic accuracy (validity) and diagnostic precision (reliability). To assess validity for qualitative variables, sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio as well as diagnostic accuracy and the odds ratio (ratio of true results to false results) are among the most appropriate tests. It is good to know that we should consider all of the above-mentioned validity estimates when judging the accuracy of that test. Moreover, for clinical purposes, it is crucial to know that reporting the diagnostic added value of a diagnostic test using the receiver operating characteristic curve should be considered. 2 Reliability (precision) as a different methodological issue of diagnostic value also should be assessed using appropriate tests. Without assessing the reliability of a diagnostic test, we should not judge the diagnostic value because a test can be acceptably accurate with no reliability. For qualitative variables, weighted kappa can be applied. Laskiewicz et al concluded that the grading of PNETs on FNA using the Ki-67 proliferation index should be assessed and is a practical parameter to report to clinicians. 1 Such a conclusion should be supported by the above methodological and statistical issues. Otherwise, in clinical practice, mismanagement of patients may occur.
Any decision in clinical practice needs to evaluate both reliability (precision) and validity (ac... more Any decision in clinical practice needs to evaluate both reliability (precision) and validity (accuracy) of a diagnostic test. Without knowledge about the reliability, any judgment would be wrong. In diagnostic accuracy research, it is essential to evaluate the diagnostic added value of a test, since a diagnostic accuracy of a single test might be excellent, however for clinical purposes it can be worthless. Like evaluating discrimination, it would be possible to estimate the diagnostic added value by applying ROC of diagnostic model with and without test results in the model.
In this letter, I discussed important limitations of applying kappa statistics to assess agreemen... more In this letter, I discussed important limitations of applying kappa statistics to assess agreement. Any conclusion in agreement needs to be supported by the methodological and statistical issues mentioned previously. Otherwise, misinterpretation cannot be avoided.
Journal of Nuclear Medicine Technology, Dec 6, 2019
Self-Reported Weight and Height in Nuclear Medicine Patients: A Common Mistake Confusing Reliabil... more Self-Reported Weight and Height in Nuclear Medicine Patients: A Common Mistake Confusing Reliability and Accuracy TO THE EDITOR: I read with great interest the article by Blum et al. recently published in the Journal of Nuclear Medicine Technology (1). The authors aimed to assess the reliability of the selfreported weight and height of nuclear medicine patients in view of recommendations for weight-dependent tracer application for imaging and therapy. In total, 824 patients (334 men and 490 women) were asked to report their weight and height before imaging or therapy, along with their level of confidence that the weight and height they were reporting were correct. Subsequently, the weight and height of each patient were measured, and body mass index, body surface area, and lean body mass were calculated. Differences between the reported and true values were compared for statistical significance. The results indicated that an over-or underestimation of weight by at least 10% was observed in 2% of the patients, and height was overestimated by 1% of the patients. Surprisingly, the authors concluded that most self-reported weights and heights of nuclear medicine patients are accurate. However, there were some methodologic issues regarding accuracy and reliability. First, it is crucial to realize that accuracy and reliability are two completely different methodologic issues. The term accuracy means the degree to which the result of a measurement, calculation, or specification conforms to the correct value or a standard. In other words, accuracy is the most important criterion for the quality of a test and refers to whether the test measures what it claims to measure. The core design for determining and measuring the accuracy of a test is a comparison between an index test and a reference standard by applying both on similar people who are suspected of having the target result of interest. The term reliability denotes refinement of a measurement, calculation, or specification, especially as represented by the number of digits given. Accuracy studies should report significant and comprehensive information together with the absolute number of true-positive, false-positive, false-negative, and true-negative results or should provide information that allows calculation of a minimum of one diagnostic performance indicator (i.e., sensitivity, specificity, predictive values, or likelihood ratio). Therefore, we recommend applying the most appropriate estimates to evaluate the accuracy of the self-reported weight and height. The Pearson r or the Spearman r can be applied to assess accuracy for quantitative variables. However, for qualitative (binary) variables, some of the well-known ways to assess accuracy include sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio (ranging from 1 to infinity; the higher the positive likelihood ratio, the more accurate the test), negative likelihood ratio (ranging from 0 to 1; the lower the negative likelihood ratio, the more accurate the test), diagnostic accuracy, and odds ratio (ratio of true results to false results) (2-8). Is There a Need for a Pediatric PET/CT Camera? TO THE EDITOR: PET imaging is commonly used in adult patients. Its use in pediatric patients is limited but indicated in certain cancers such as lymphoma, sarcoma, neuroblastoma, and central nervous system tumors (1). The main limitation of PET imaging is its relatively limited spatial resolution in detecting small lesions, mainly because of the noncollinearity of the 511-keV annihilation photons, positron range, detector scatter, and parallax error (2-5). However, small-animal PET scanners have higher spatial resolution than standard human PET scanners (approximately 1 mm vs. 4-6 mm)
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