Lenore Arab

Gertner Institute for Epidemiology and Health Policy Research, Tell Afif, Tel Aviv, Israel

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Publications (20)76.22 Total impact

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    ABSTRACT: Most statistical methods that adjust analyses for dietary measurement error treat an individual's usual intake as a fixed quantity. However, usual intake, if defined as average intake over a few months, varies over time. We describe a model that accounts for such variation and for the proximity of biomarker measurements to self-reports within the framework of a meta-analysis, and apply it to the analysis of data on energy, protein, potassium, and sodium from a set of five large validation studies of dietary self-report instruments using recovery biomarkers as reference instruments. We show that this time-varying usual intake model fits the data better than the fixed usual intake assumption. Using this model, we estimated attenuation factors and correlations with true longer-term usual intake for single and multiple 24-hour dietary recalls (24HRs) and food frequency questionnaires (FFQs) and compared them with those obtained under the "fixed" method. Compared with the fixed method, the estimates using the time-varying model showed slightly larger values of the attenuation factor and correlation coefficient for FFQs and smaller values for 24HRs. In some cases, the difference between the fixed method estimate and the new estimate for multiple 24HRs was substantial. With the new method, while four 24HRs had higher estimated correlations with truth than a single FFQ for absolute intakes of protein, potassium, and sodium, for densities the correlations were approximately equal. Accounting for the time element in dietary validation is potentially important, and points toward the need for longer-term validation studies.
    No preview · Article · Sep 2015 · Epidemiology (Cambridge, Mass.)
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    ABSTRACT: We pooled data from 5 large validation studies (1999-2009) of dietary self-report instruments that used recovery biomarkers as referents, to assess food frequency questionnaires (FFQs) and 24-hour recalls (24HRs). Here we report on total potassium and sodium intakes, their densities, and their ratio. Results were similar by sex but were heterogeneous across studies. For potassium, potassium density, sodium, sodium density, and sodium:potassium ratio, average correlation coefficients for the correlation of reported intake with true intake on the FFQs were 0.37, 0.47, 0.16, 0.32, and 0.49, respectively. For the same nutrients measured with a single 24HR, they were 0.47, 0.46, 0.32, 0.31, and 0.46, respectively, rising to 0.56, 0.53, 0.41, 0.38, and 0.60 for the average of three 24HRs. Average underreporting was 5%-6% with an FFQ and 0%-4% with a single 24HR for potassium but was 28%-39% and 4%-13%, respectively, for sodium. Higher body mass index was related to underreporting of sodium. Calibration equations for true intake that included personal characteristics provided improved prediction, except for sodium density. In summary, self-reports capture potassium intake quite well but sodium intake less well. Using densities improves the measurement of potassium and sodium on an FFQ. Sodium:potassium ratio is measured much better than sodium itself on both FFQs and 24HRs. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.
    No preview · Article · Mar 2015 · American journal of epidemiology
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    L Arab · A Ang
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    ABSTRACT: To examine the association between walnut consumption and measures of cognitive function in the US population. Nationally representative cross sectional study using 24 hour dietary recalls of intakes to assess walnut and other nut consumption as compared to the group reporting no nut consumption. 1988-1994 and 1999-2002 rounds of the National Health and Nutrition Examination Survey (NHANES). Representative weighted sample of US adults 20 to 90 years of age. The Neurobehavioral Evaluation System 2 (NES2), consisting of simple reaction time (SRTT), symbol digit substitution (SDST), the single digit learning (SDLT), Story Recall (SRT) and digit-symbol substitution (DSST) tests. Adults 20-59 years old reporting walnut consumption of an average of 10.3 g/d required 16.4ms less time to respond on the SRTT, P=0.03, and 0.39s less for the SDST, P=0.01. SDLT scores were also significantly lower by 2.38s (P=0.05). Similar results were obtained when tertiles of walnut consumption were examined in trend analyses. Significantly better outcomes were noted in all cognitive test scores among those with higher walnut consumption (P < 0.01). Among adults 60 years and older, walnut consumers averaged 13.1 g/d, scored 7.1 percentile points higher, P=0.03 on the SRT and 7.3 percentile points higher on the DSST, P=0.05. Here also trend analyses indicate significant improvements in all cognitive test scores (P < 0.01) except for SRTT (P = 0.06) in the fully adjusted models. These significant, positive associations between walnut consumption and cognitive functions among all adults, regardless of age, gender or ethnicity suggest that daily walnut intake may be a simple beneficial dietary behavior.
    Preview · Article · Mar 2015 · The Journal of Nutrition Health and Aging
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    ABSTRACT: We pooled data from 5 large validation studies of dietary self-report instruments that used recovery biomarkers as references to clarify the measurement properties of food frequency questionnaires (FFQs) and 24-hour recalls. The studies were conducted in widely differing US adult populations from 1999 to 2009. We report on total energy, protein, and protein density intakes. Results were similar across sexes, but there was heterogeneity across studies. Using a FFQ, the average correlation coefficients for reported versus true intakes for energy, protein, and protein density were 0.21, 0.29, and 0.41, respectively. Using a single 24-hour recall, the coefficients were 0.26, 0.40, and 0.36, respectively, for the same nutrients and rose to 0.31, 0.49, and 0.46 when three 24-hour recalls were averaged. The average rate of under-reporting of energy intake was 28% with a FFQ and 15% with a single 24-hour recall, but the percentages were lower for protein. Personal characteristics related to under-reporting were body mass index, educational level, and age. Calibration equations for true intake that included personal characteristics provided improved prediction. This project establishes that FFQs have stronger correlations with truth for protein density than for absolute protein intake, that the use of multiple 24-hour recalls substantially increases the correlations when compared with a single 24-hour recall, and that body mass index strongly predicts under-reporting of energy and protein intakes.
    No preview · Article · Jun 2014 · American Journal of Epidemiology
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    Lenore Arab · Faraz Khan · Helen Lam
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    ABSTRACT: The present analysis was conducted in response to inconsistent epidemiologic studies on the relation between consumption of tea and cardiovascular diseases. We undertook a literature review of the consistency and strength of the associations between tea and cardiovascular diseases on the basis of published observational studies and meta-analyses addressing tea or tea flavonoids and cardiovascular disease risk. We performed a search in 3 databases for meta-analyses and compared them with studies they subsumed. We performed an additional search for subsequent studies to determine whether the conclusions were consistent. A wealth of epidemiologic studies have been conducted and summarized in 5 meta-analyses on either tea consumption or flavonoid consumption and cardiovascular disease or the subset of stroke. Heterogeneity of effect was seen when the outcome included all cardiovascular diseases. In the case of stroke, a consistent, dose-response association with tea consumption on both incidence and mortality was noted with RRs of 0.80 (95% CI: 0.65, 0.98) for flavonoids and 0.79 (95% CI: 0.73, 0.85) for tea when high and low intakes were compared or the addition of 3 cups/d was estimated. Thus, the strength of this evidence supports the hypothesis that tea consumption might lower the risk of stroke.
    Preview · Article · Oct 2013 · American Journal of Clinical Nutrition
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    ABSTRACT: Background Evidence is mixed regarding sugar-sweetened beverage (SSB) intake and adiposity among adults, perhaps due to reporting bias.Objective To determine the impact of reporting bias on any associations between increased SSB intake and overweight/obesity.DesignBeverage intake and overweight/obese status (BMI 25 kg/m2) was examined among adults from a dietary assessment and doubly labeled water study (n=250). Four web-based, 24-hour recalls assessed dietary intake. SSB intake was categorized as no intake, 1-99 kcals per day, and >99 kcals per day. Logistic regression models adjusted for total caloric intake, age, race, education and diet quality compared SSB intake to overweight/obese status. To investigate dietary self-reporting bias, analyses were replicated in a subset of 'true reporters': those with self-reported total caloric intake within 25% of total energy expenditure per doubly labeled water assessments (n=108).ResultsOne-half of participants were overweight/obese; more overweight/obese participants consumed SSB than normal weight participants (69 vs 47% P<0.001). Intake of other beverages did not differ by adiposity. Less White participants (48%) consumed SSB compared to African-American participants (68% P=0.002). Compared to no intake, SSB intake up to the median intake doubled the risk of being overweight/obese (OR: 2.1, 95% CI: 1.0-4.3; P=0.046), and SSB intake over the median more than doubled the risk (OR: 2.6, 95% CI: 1.2-6.0; P=0.018). When limited to true reporters, SSB intake significantly increased the risk of being overweight/obese by nearly 4 fold.Conclusion Underreporting of SSB intake may be attenuating true associations of SSB intake and the risk of being overweight/obese.International Journal of Obesity accepted article preview online, 19 July 2013. doi:10.1038/ijo.2013.130.
    Full-text · Article · Jul 2013 · International journal of obesity (2005)
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    ABSTRACT: The timing of energy intake is a modifiable behaviour that may influence energy regulation and the risk of obesity. We examined the associations of energy intake in the morning, midday and evening with body mass index (BMI) (n = 239). Cross-sectional analyses were performed using data from the University of California, Los Angeles Energetics Study. Energy intake was assessed using three 24-h dietary recalls and stratified by time-of-day: morning (00.00 h to 11.00 h), midday (11.00 h to 17.00 h) and evening (17.00 h to 00.00 h). Sensitivity analysis was conducted among 'true-reporters', whose self-reported energy intake was ±25% of total energy expenditure measured by doubly-labelled water (n = 99). Logistic regression models were performed adjusting for age, sex, race, education, total daily energy intake and physical activity. Energy intake in the morning was not associated with BMI. Participants who consumed ≥33% (versus <33%) of their daily energy intake at 12.00 h were (nonsignificantly) less likely to be overweight/obese [odds ratio (OR) = 0.68; 95% confidence interval (CI) = 0.37-1.24] and this association was stronger and statistically significant among true-reporters (OR = 0.34; 95% CI = 0.12-0.95). Those who consumed ≥33% of daily energy intake in the evening were two-fold more likely overweight/obese (OR = 2.00; 95% CI = 1.03-3.89), although this association was not significant among true-reporters (OR = 2.10; 95% CI = 0.60-7.29). These data indicate that eating more of the day's total energy intake at midday is associated with a lower risk of being overweight/obese, whereas consuming more in the evening is associated with a higher risk. Randomised trials are needed to test whether shifting energy intake earlier in the day could have a regulatory effect with respect to reducing intake in the evening, thereby promoting weight loss and maintenance.
    No preview · Article · Jun 2013 · Journal of Human Nutrition and Dietetics
  • Lenore Arab · Faraz Khan · Helen Lam
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    ABSTRACT: A systematic literature review of human studies relating caffeine or caffeine-rich beverages to cognitive decline reveals only 6 studies that have collected and analyzed cognition data in a prospective fashion that enables study of decline across the spectrum of cognition. These 6 studies, in general, evaluate cognitive function using the Mini Mental State Exam and base their beverage data on FFQs. Studies included in our review differed in their source populations, duration of study, and most dramatically in how their analyses were done, disallowing direct quantitative comparisons of their effect estimates. Only one of the studies reported on all 3 exposures, coffee, tea, and caffeine, making comparisons of findings across studies more difficult. However, in general, it can be stated that for all studies of tea and most studies of coffee and caffeine, the estimates of cognitive decline were lower among consumers, although there is a lack of a distinct dose response. Only a few measures showed a quantitative significance and, interestingly, studies indicate a stronger effect among women than men.
    No preview · Article · Jan 2013 · Advances in Nutrition
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    Regan Bailey · Lenore Arab

    Preview · Article · Sep 2012 · Advances in Nutrition
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    ABSTRACT: Other than the in vitro erythrocyte hemolysis test, no valid biomarkers of vitamin E status currently exist. We hypothesized that the urinary vitamin E metabolite α-carboxyethyl hydroxychroman (α-CEHC) could serve as a biomarker. The relations between urinary α-CEHC, plasma α-tocopherol, and vitamin E intakes were assessed by using a previously validated multipass, Web-based, 24-h self-administered dietary recall, and we concurrently collected plasma and 24-h urine samples from 233 participants of both sexes. Median vitamin E intakes were 9.7 mg α-tocopherol/d. Intakes were correlated with plasma α-tocopherol (R = 0.40, P < 0.001) and urinary α-CEHC (R = 0.42, P < 0.001); these correlations were essentially unchanged after multivariate adjustments. On the basis of multiple regression analysis, urinary α-CEHC excretion increased by ∼0.086 μmol/g creatinine (95% CI: 0.047, 0.125) for every 1-mg (2.3-μmol) increase in dietary α-tocopherol. Urinary α-CEHC excretion remained at a plateau (median: 1.39 μmol/g creatinine) until dietary intakes of α-tocopherol exceeded 9 mg α-tocopherol/d. The inflection point at which vitamin E metabolism increased was estimated to be at an intake of 12.8 mg α-tocopherol/d. Daily excretion of >1.39 μmol α-CEHC/g creatinine is associated with a greater than adequate α-tocopherol status, as evidenced by increased vitamin E metabolism and excretion. Thus, urinary α-CEHC is a valid biomarker of α-tocopherol status that can be used to set a value for the Estimated Adequate Requirement of vitamin E.
    No preview · Article · Sep 2012 · American Journal of Clinical Nutrition
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    ABSTRACT: Background: Successfully changing patients' dietary behavior is a challenging problem in the management of chronic kidney disease (CKD). We conducted a pilot study to test the feasibility and acceptability of an Internet-based, self-administered, dietary assessment tool equipped with instructional feedback, aimed at facilitating dietary adherence to disease-specific nutritional guidelines among CKD stage IV patients while reducing resource burdens on providers. Methods: Focus groups were used to develop a user-friendly dietary reporting format. The report was then calibrated to the dietary guidelines outlined by Kidney Disease Outcomes Quality Initiative (K/DOQI) and incorporated into the assessment tool. Elements of the report were developed based on the "transtheoretical model of behavior change" theory, aimed at facilitating patients to enter the action stage of change. The tool was later deployed in a nephrology care site at an academic medical center, where 12 patients diagnosed with stage IV CKD (late-stage, predialysis) completed a dietary assessment before their provider encounter as well as questionnaires gauging their computer literacy, nutritional education history, nutritional knowledge and awareness, and acceptability of the tool. The report was made available to the provider during the clinical encounter, and both patient and physician perception of the report's utility was assessed after the encounter. Results: Approximately 25% to 30% of the patients were severely noncompliant to the K/DOQI guidelines for each nutrient. Awareness about the role of diet in CKD management was widely variable, ranging from 0% to 58% of the patients over different nutrients. All of the patients successfully completed the Web-based dietary assessment. Eighty-four percent of the patients positively rated the tool on its ability to record the patients' dietary data, 58% noted the tool was always able to satisfactorily estimate portion sizes, and 50% thought the navigation was easy or very easy. Eleven of the 12 patients were satisfied with the time taken (range: 10 to 40 minutes, median time: 20 minutes) to complete the dietary assessment. Patients and physicians differed considerably in their perception of the use of the report during the clinical encounter. Conclusion: Dietary knowledge and adherence to K/DOQI guidelines among CKD patients is suboptimal. However, interest and motivation is high. Web-based tools are well accepted among CKD patients as an aid to assessing dietary adherence to K/DOQI guidelines and may pose a cost-effective approach to bridging the adherence gap.
    No preview · Article · Jul 2012 · Journal of Renal Nutrition
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    ABSTRACT: The risk of developing tuberculosis (TB) may be related to nutritional status. To determine the impact of nutritional status on TB incidence, the authors analyzed data from the First National Health and Nutrition Examination Survey (NHANES I) Epidemiologic Follow-up Study (NHEFS). NHANES I collected information on a probability sample of the US population in 1971-1975. Adults were followed up in 1982-1992. Incident TB cases were ascertained through interviews, medical records, and death certificates. TB incidences were compared across different levels of nutritional status after controlling for potential confounding using proportional hazards regression appropriate to the complex sample design. TB incidence among adults with normal body mass index was 24.7 per 100,000 person-years (95% confidence interval (CI): 13.0, 36.3). In contrast, among persons who were underweight, overweight, and obese, estimated TB incidence rates were 260.2 (95% CI: 98.6, 421.8), 8.9 (95% CI: 2.2, 15.6), and 5.1 (95% CI: 0.0, 10.5) per 100,000 person-years, respectively. Adjusted hazard ratios were 12.43 (95% CI: 5.75, 26.95), 0.28 (95% CI: 0.13, 0.63), and 0.20 (95% CI: 0.07, 0.62), respectively, after controlling for demographic, socioeconomic, and medical characteristics. A low serum albumin level also increased the risk of TB, but low vitamin A, thiamine, riboflavin, and iron status did not. A population's nutritional profile is an important determinant of its TB incidence.
    Full-text · Article · Jul 2012 · American journal of epidemiology
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    ABSTRACT: Marketing strategies and food offerings in hospital cafeterias can impact dietary choices. Using a survey adapted to assess food environments, the purpose of this study was to assess the food environment available to patients, staff, and visitors at the food-service venues in all 14 California children's hospitals. We modified a widely-used tool to create the Nutritional Environment Measures Survey for Cafeterias (NEMS-C) by partnering with a hospital wellness committee. The NEMS-C summarizes the number of healthy items offered, whether calorie labeling is present, if there is signage promoting healthy or unhealthy foods, pricing structure, and the presence of unhealthy combination meals. The range of possible scores is zero (unhealthy) to 37 (healthy). We directly observed the food-service venues at all 14 tertiary care children's hospitals in California and scored them. Inter-rater reliability showed 89% agreement on the assessed items. For the 14 hospitals, the mean score was 19.1 (SD = 4.2; range, 13-30). Analysis revealed that nearly all hospitals offered diet drinks, low-fat milk, and fruit. Fewer than one-third had nutrition information at the point of purchase and 30% had signs promoting healthy eating. Most venues displayed high calorie impulse items such as cookies and ice cream at the registers. Seven percent (7%) of the 384 entrees served were classified as healthy according to NEMS criteria. Most children's hospitals' food venues received a mid-range score, demonstrating there is considerable room for improvement. Many inexpensive options are underused, such as providing nutritional information, incorporating signage that promotes healthy choices, and not presenting unhealthy impulse items at the register.
    Full-text · Article · Nov 2011 · Academic pediatrics
  • Lenore Arab

    No preview · Article · Nov 2011 · Nutrition and Cancer
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    ABSTRACT: High levels of circulating advanced glycation end products (AGE) are associated with cardiovascular disease, diabetes, chronic kidney disease, and increased mortality, but factors that influence levels of circulating AGE are not well known. Our objective was to characterize the relationship between serum carboxymethyl-lysine (CML), a major circulating AGE, and body composition in adults. In a cross-sectional study, total body DXA was performed and serum CML was measured in 592 adults, aged 26-93 y, from the Baltimore Longitudinal Study of Aging. Median (25th, 75th percentile) CML concentrations were 2.26 (1.86, 2.67) μmol/L. Total fat mass [β = -0.17 (95% CI -0.10, -0.24); P < 0.0001], truncal fat mass [β = -0.17 (95% CI -0.10, -0.25); P < 0.0001], and appendicular fat mass [β = -0.13 (95% CI -0.05, -0.20); P = 0.001] per 1 SD increase were inversely associated with serum CML in separate multivariate linear regression models, adjusting for age, sex, BMI, systolic blood pressure, TG, HDL cholesterol, and renal function. Lean body mass was not independently associated with serum CML. These findings suggest that serum CML concentration is strongly affected by body fat, possibly because CML is preferentially deposited in fat tissue or because adipocytes affect the metabolism of AGE.
    Full-text · Article · Sep 2011 · Journal of Nutrition
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    ABSTRACT: Advanced glycation end products (AGEs) are implicated in the pathogenesis of atherosclerosis, diabetes and kidney disease. The objective was to describe dietary intake, the dominant source of exposure to AGEs, with carboxymethyl-lysine (CML), a major AGE, in serum and urine, respectively. Serum and urinary CML were measured in 261 adults, aged 21-69 years, and compared with diet as assessed by six separate 24-h dietary recalls. Median (25th, 75th percentile) serum and urinary CML concentrations were 686 (598, 803) μg/l and 1023 (812, 1238) μg/gm creatinine. There was no correlation between serum and urinary CML (r=-0.02, P=0.78). Serum CML was positively correlated with intake of soy, fruit juice, cold breakfast cereal, non-fat milk, whole grains, fruit, non-starchy vegetables and legumes, and negatively correlated with intake of red meat. Intake of fast food was not significantly correlated with serum CML. Urinary CML was positively correlated with intake of starchy vegetables, whole grains, sweets, nuts/seeds and chicken, and negatively correlated with intake of fast foods. Intake of AGE-rich foods such as fried chicken, French fries, bacon/sausage and crispy snacks were not significantly correlated with serum or urinary CML, except for a significant negative correlation between fried chicken and serum CML. These findings suggest that the high consumption of foods considered high in CML is not a major determinant of either serum or urinary CML. Further work is needed to understand the relationship of AGEs in blood and urine with the metabolism of dietary AGEs.
    Preview · Article · Jul 2011 · European journal of clinical nutrition
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    ABSTRACT: The accuracy of dietary recalls might be enhanced by providing participants with photo images of foods they consumed during the test period. We examined the feasibility of a system (Image-Diet Day) that is a user-initiated camera-equipped mobile phone that is programmed to automatically capture and transmit images to a secure website in conjunction with computer-assisted, multipass, 24-h dietary recalls in 14 participants during 2007. Participants used the device during eating periods on each of the three independent days. Image processing filters successfully eliminated underexposed, overexposed and blurry images. The captured images were accessed by the participants using the ImageViewer software while completing the 24-h dietary recall on the following day. None of the participants reported difficulty using the ImageViewer. Images were deemed 'helpful' or 'sort of helpful' by 93% of participants. A majority (79%) of users reported having no technical problems, but 71% rated the burden of wearing the device as somewhat to very difficult, owing to issues such as limited battery life, self-consciousness about wearing the device in public and concerns about the field of view of the camera. Overall, these findings suggest that automated imaging is a promising technology to facilitate dietary recall. The challenge of managing the thousands of images generated can be met. Smaller devices with a broader field of view may aid in overcoming self-consciousness of the user with using or wearing the device.
    Preview · Article · May 2011 · European journal of clinical nutrition
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    ABSTRACT: This paper presents an assisted recall system, Rewind, that employs automatic image capture on mobile phones and filtering of images for end-user viewing. The usability of image-based assisted recall systems is limited by the large number of images through which the user must navigate. Rewind is a scalable system of everyday mobile phones and supporting web services that we developed to explore how client-and server-side image processing can be used to both lower bandwidth needs and streamline user navigation. It has been in use since August 2007 as part of a pilot study super-vised by an epidemiologist to evaluate its utility for improving re-call of dietary intake, as well as other shorter and more exploratory trials. While the system is designed to accommodate a range of image processing algorithms, in this first prototype we rely on sim-ple filtering techniques to evaluate our system concept. We present performance results for a configuration in which the processing oc-curs on the server, and then compare this to processing on the mo-bile phones. Simple image processing on the phone can address the narrow-band and intermittent upload channels that characterize cellular infrastructure, while more sophisticated processing tech-niques can be implemented on the server to further reduce the num-ber of images displayed to users.
    Preview · Article · Jan 2008
  • Nataliya Volkova · Lenore Arab
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    ABSTRACT: An evidence-based evaluation of peer-reviewed original research published during 1980 to 2004 and examining the relationship between hemoglobin and/or hematocrit values and all-cause mortality in dialysis patients was conducted to compare the studies' designs, analytic strategies, and results. The search targeted MEDLINE and EMBASE and included publications referenced in the National Kidney Foundation-Kidney Disease Outcomes Quality Initiative Anemia Guidelines. Both randomized clinical trials (RCTs) and observational studies were considered. Of 7 RCTs and 20 observational studies identified, 5 trials and 13 studies were included in evidence tables. The trials were underpowered to study mortality and enrolled different patient populations, limiting their generalizability. Although none reached statistical significance, trials focusing on a general dialysis population tended to show either no effect or a benefit of greater hemoglobin level target, whereas trials enrolling cardiac patients suggested increased mortality associated with greater hemoglobin levels. The observational studies were heterogeneous in design, used varying exposure categorizations, and controlled for different covariates, but generally were supportive of increased mortality associated with a hemoglobin level less than the reference range. Evidence of benefits or risks of hemoglobin levels greater than the reference was variable. RCT-based evidence relating hemoglobin and/or hematocrit values to mortality in dialysis patients is limited. The relationship may be modified by the presence of preexisting conditions (cardiac disease). The published literature is insufficient for generalization of risks or benefits of a hemoglobin level greater than 11 to 12 g/dL (>110 to 120 g/L). There is a need for better designed RCTs focusing on mortality as a primary outcome and enrolling patients without cardiac disease. Observational studies should adequately control for relevant confounders (eg, baseline comorbidities) and assess effect modification in the analysis.
    No preview · Article · Feb 2006 · American Journal of Kidney Diseases

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Publication Stats

286 Citations
76.22 Total Impact Points


  • 2014-2015
    • Gertner Institute for Epidemiology and Health Policy Research
      Tell Afif, Tel Aviv, Israel
  • 2011-2015
    • University of California, Los Angeles
      • Department of Medicine
      Los Ángeles, California, United States
  • 2012
    • Centers for Disease Control and Prevention
      • Division of Tuberculosis Elimination
      Атланта, Michigan, United States