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Ralph B. D'Agostino

Bio: Ralph B. D'Agostino is an academic researcher from Wake Forest University. The author has contributed to research in topics: Framingham Heart Study & Framingham Risk Score. The author has an hindex of 226, co-authored 1287 publications receiving 229636 citations. Previous affiliations of Ralph B. D'Agostino include VA Boston Healthcare System & University of Illinois at Urbana–Champaign.


Papers
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Book ChapterDOI
19 Oct 2017
TL;DR: In this paper, the authors discuss goodness-of-fit tests designed to test formally the appropriateness or adequacy of the normal distribution as a model for the underlying phenomenon from which data were generated.
Abstract: The chapter deals with the second class of use and discusses goodness-of-fit tests designed to test formally the appropriateness or adequacy of the normal distribution as a model for the underlying phenomenon from which data were generated. The single most used distribution in statistical analysis is the normal distribution. The chapter discusses tests that assume a complete random sample is available for analysis. It purposes tests for normality grouped into five categories, chi-square test, empirical distribution function tests, moment tests, regression tests, and miscellaneous tests. A number of investigators have considered extending and modifying the Shapiro-Wilk test. Spiegelhalter used the theory of most powerful location and scale invariant tests to develop tests of normality against the uniform and the double exponential distributions. Results of power studies are not the only means for judging or comparing the normality tests.

111 citations

Journal ArticleDOI
TL;DR: Whether testosterone or sex hormone–binding globulin (SHBG) is independently associated with the risk of metabolic syndrome is determined and data do not reveal an independent prospective relationship between testosterone and metabolic syndrome in men.
Abstract: OBJECTIVE The association between total testosterone and metabolic syndrome has prompted speculation that low testosterone contributes to the pathophysiology of metabolic syndrome in men. We determined whether testosterone or sex hormone–binding globulin (SHBG) is independently associated with the risk of metabolic syndrome. RESEARCH DESIGN AND METHODS Cross-sectional relationships of hormone levels with metabolic syndrome were assessed in a sample of men in generation 2 of the Framingham Heart Study (FHS) who did not receive testosterone or androgen-deprivation therapy ( n = 1,625) and confirmed in a validation sample of men in FHS generation 3 ( n = 1,912). Hormone levels in generation 2 examination 7 were related prospectively to incident metabolic syndrome 6.6 years later at examination 8. Testosterone was measured using liquid chromatography–tandem mass spectrometry, SHBG was measured by immunofluorometric assay, and free testosterone was calculated. Metabolic syndrome was defined using the National Cholesterol Education Program Adult Treatment Panel III criteria. RESULTS Cross-sectionally, testosterone and SHBG were more strongly associated with metabolic syndrome than free testosterone in the training sample. SHBG, but not testosterone or free testosterone, was significantly associated with metabolic syndrome after adjusting for age, smoking, BMI, and insulin sensitivity (homeostasis model assessment of insulin resistance [HOMA-IR]). These findings were confirmed in a validation sample. Longitudinally, SHBG at examination 7, but not testosterone or free testosterone, was associated with incident metabolic syndrome at examination 8 after adjusting for age, smoking, BMI, and HOMA-IR. Multivariable analyses suggested that age, BMI, and insulin sensitivity independently affect SHBG and testosterone levels and the risk of metabolic syndrome and its components. CONCLUSIONS SHBG, but not testosterone, is independently associated with the risk of metabolic syndrome. These data do not reveal an independent prospective relationship between testosterone and metabolic syndrome in men.

110 citations

Journal ArticleDOI
TL;DR: Older, low-income, African American women have perceived barriers to cancer screening, educational and cancer knowledge detriments, and a lack of health-related social support that may decrease adherence to mammography screening.
Abstract: Purpose/objectives To explore psychosocial correlates of older African American women's adherence to annual mammography screening, including cancer fatalism, dispositional optimism, social support, knowledge of breast cancer screening guidelines, perceptions of general health, and components of the Health Belief Model (HBM), and to examine factors associated with annual mammography screening. Design Cross-sectional survey. Setting Central North Carolina. Sample 198 African American women aged 50-98 years living in low-income housing. Methods Women attended group sessions at low-income housing complexes and completed questionnaires. Differences between women who had or did not have a mammogram in the previous year were explored using correlate variables associated with the HBM. Stepwise multivariable regression models were fit to explore factors associated with social support and significant components of the HBM. Main research variables Demographics, cancer fatalism, dispositional optimism, social support, perceptions of general health, components of the HBM, and mammography in the past year. Findings The groups did not differ by age, education, marital status, having a friend or family member with breast cancer, ever having had a clinical breast examination, self-rated health, cancer fatalism, dispositional optimism, or feelings about the seriousness of and their susceptibility to breast cancer. The groups differed significantly on mammogram-related variables, how often women should have clinical breast examinations, benefits and barriers to mammography screening, and social support. Stepwise multivariable regression analyses showed that dispositional optimism and social support were related significantly to perception of benefits; education, dispositional optimism, and cancer fatalism were related to barriers; and dispositional optimism was related to social support. Conclusions Older, low-income, African American women have perceived barriers to cancer screening, educational and cancer knowledge detriments, and a lack of health-related social support that may decrease adherence to mammography screening. Implications for nursing The next step is to develop culturally appropriate educational interventions that increase knowledge about breast cancer and screening guidelines, enhance health-related social support, and address barriers and perhaps cancer fatalism in older, low-income, African American women.

110 citations

Journal ArticleDOI
TL;DR: The data suggest the interchangeability of the recall and record methods and their preference over the food frequency questionnaire for mean estimates of group nutrient intake, and the need to develop and evaluate short methods of diet assessment in specific populations of interest.
Abstract: We compared estimates of nutrient intake by three diet assessment methods (24-hour recall, 3-day food record, food frequency questionnaire) in a random sample of 73 females and 77 males from the Framingham Offspring/Spouse Study. The results differed according to analytic method. Estimates of group mean intake from the 24-hour recall and 3-day records were similar in both women and men, with differences of less than 10% for most nutrients. The estimates of mean intake calculated from the food frequency questionnaire generally differed from those obtained by the other methods, with higher estimated intakes in women and generally lower estimated intakes in men. Spearman rank correlations between the individuals' nutrient intakes estimated by the three diet assessment methods were modest (r = 0.08-0.68, most below 0.50) and comparable in the comparisons of the 24-hour recall or food frequency questionnaire with the 3-day records. Our data suggest the interchangeability of the recall and record methods and their preference over the food frequency questionnaire for mean estimates of group nutrient intake. The food frequency questionnaire appears to be of some utility in ranking individuals according to the usual intake, although these data are not informative in comparing this method with multiple days of recall or records beyond 3 days. This research underscores the need to develop and evaluate short methods of diet assessment in specific populations of interest.

109 citations

Journal ArticleDOI
TL;DR: APoB improves risk assessment of future coronary heart disease events over and beyond LDL-C or non-HDL-C, which is consistent with coronary risk being more closely related to the number of atherogenic apoB particles than to the mass of cholesterol within them.
Abstract: AimsAnalyses using conventional statistical methodologies have yielded conflicting results as to whether low-density lipoprotein cholesterol (LDL-C) or non-high-density lipoprotein cholesterol (non-HDL-C) or apolipoprotein B (apoB) is the best marker of the apoB-associated risk of coronary heart disease. The aim of this study was to determine the additional value of apoB beyond LDL-C or non-HDL-C as a predictor of coronary heart disease.Methods and resultsFor each patient from the Framingham Offspring Cohort aged 40–75 years (n = 2966), we calculated the extent to which the observed apoB differed from the expected apoB based on their LDL-C or non-HDL-C. We added this difference to a Cox model predicting new onset coronary heart disease over a maximum of 20 years adjusting for standard risk factors plus LDL-C or non-HDL. The difference between observed and expected apoB over LDL-C or non-HDL-C was highly prognostic of future coronary heart disease events: adjusted hazard ratios 1.26 (95% confidence interva...

109 citations


Cited by
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Journal ArticleDOI
TL;DR: G*Power 3 provides improved effect size calculators and graphic options, supports both distribution-based and design-based input modes, and offers all types of power analyses in which users might be interested.
Abstract: G*Power (Erdfelder, Faul, & Buchner, 1996) was designed as a general stand-alone power analysis program for statistical tests commonly used in social and behavioral research. G*Power 3 is a major extension of, and improvement over, the previous versions. It runs on widely used computer platforms (i.e., Windows XP, Windows Vista, and Mac OS X 10.4) and covers many different statistical tests of thet, F, and χ2 test families. In addition, it includes power analyses forz tests and some exact tests. G*Power 3 provides improved effect size calculators and graphic options, supports both distribution-based and design-based input modes, and offers all types of power analyses in which users might be interested. Like its predecessors, G*Power 3 is free.

40,195 citations

Journal ArticleDOI
21 May 2003-JAMA
TL;DR: The most effective therapy prescribed by the most careful clinician will control hypertension only if patients are motivated, and empathy builds trust and is a potent motivator.
Abstract: "The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure" provides a new guideline for hypertension prevention and management. The following are the key messages(1) In persons older than 50 years, systolic blood pressure (BP) of more than 140 mm Hg is a much more important cardiovascular disease (CVD) risk factor than diastolic BP; (2) The risk of CVD, beginning at 115/75 mm Hg, doubles with each increment of 20/10 mm Hg; individuals who are normotensive at 55 years of age have a 90% lifetime risk for developing hypertension; (3) Individuals with a systolic BP of 120 to 139 mm Hg or a diastolic BP of 80 to 89 mm Hg should be considered as prehypertensive and require health-promoting lifestyle modifications to prevent CVD; (4) Thiazide-type diuretics should be used in drug treatment for most patients with uncomplicated hypertension, either alone or combined with drugs from other classes. Certain high-risk conditions are compelling indications for the initial use of other antihypertensive drug classes (angiotensin-converting enzyme inhibitors, angiotensin-receptor blockers, β-blockers, calcium channel blockers); (5) Most patients with hypertension will require 2 or more antihypertensive medications to achieve goal BP (<140/90 mm Hg, or <130/80 mm Hg for patients with diabetes or chronic kidney disease); (6) If BP is more than 20/10 mm Hg above goal BP, consideration should be given to initiating therapy with 2 agents, 1 of which usually should be a thiazide-type diuretic; and (7) The most effective therapy prescribed by the most careful clinician will control hypertension only if patients are motivated. Motivation improves when patients have positive experiences with and trust in the clinician. Empathy builds trust and is a potent motivator. Finally, in presenting these guidelines, the committee recognizes that the responsible physician's judgment remains paramount.

24,988 citations

28 Jul 2005
TL;DR: PfPMP1)与感染红细胞、树突状组胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作�ly.
Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1(PfPMP1)与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员,通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

18,940 citations

Journal ArticleDOI
TL;DR: Because of the increased complexity of analysis and interpretation of clinical genetic testing described in this report, the ACMG strongly recommends thatclinical molecular genetic testing should be performed in a Clinical Laboratory Improvement Amendments–approved laboratory, with results interpreted by a board-certified clinical molecular geneticist or molecular genetic pathologist or the equivalent.

17,834 citations

Journal ArticleDOI
TL;DR: In those older than age 50, systolic blood pressure of greater than 140 mm Hg is a more important cardiovascular disease (CVD) risk factor than diastolic BP, and hypertension will be controlled only if patients are motivated to stay on their treatment plan.
Abstract: The National High Blood Pressure Education Program presents the complete Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure. Like its predecessors, the purpose is to provide an evidence-based approach to the prevention and management of hypertension. The key messages of this report are these: in those older than age 50, systolic blood pressure (BP) of greater than 140 mm Hg is a more important cardiovascular disease (CVD) risk factor than diastolic BP; beginning at 115/75 mm Hg, CVD risk doubles for each increment of 20/10 mm Hg; those who are normotensive at 55 years of age will have a 90% lifetime risk of developing hypertension; prehypertensive individuals (systolic BP 120-139 mm Hg or diastolic BP 80-89 mm Hg) require health-promoting lifestyle modifications to prevent the progressive rise in blood pressure and CVD; for uncomplicated hypertension, thiazide diuretic should be used in drug treatment for most, either alone or combined with drugs from other classes; this report delineates specific high-risk conditions that are compelling indications for the use of other antihypertensive drug classes (angiotensin-converting enzyme inhibitors, angiotensin-receptor blockers, beta-blockers, calcium channel blockers); two or more antihypertensive medications will be required to achieve goal BP (<140/90 mm Hg, or <130/80 mm Hg) for patients with diabetes and chronic kidney disease; for patients whose BP is more than 20 mm Hg above the systolic BP goal or more than 10 mm Hg above the diastolic BP goal, initiation of therapy using two agents, one of which usually will be a thiazide diuretic, should be considered; regardless of therapy or care, hypertension will be controlled only if patients are motivated to stay on their treatment plan. Positive experiences, trust in the clinician, and empathy improve patient motivation and satisfaction. This report serves as a guide, and the committee continues to recognize that the responsible physician's judgment remains paramount.

14,975 citations