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https://www.readbyqxmd.com/read/29165572/principled-approaches-to-missing-data-in-epidemiologic-studies
#1
Neil J Perkins, Stephen R Cole, Ofer Harel, Eric J Tchetgen Tchetgen, BaoLuo Sun, Emily M Mitchell, Enrique F Schisterman
Principled methods to appropriately analyze missing data have long existed; however, broad implementation of these methods remains challenging. In this and companion papers, we discuss issues of missing data in the epidemiologic literature. We provide details regarding missing data mechanisms and nomenclature and motivate principled analyses through a detailed comparison of multiple imputation and inverse probability weighting. We do so in the setting of a masked data-analytic challenge with missing data induced by known mechanisms to data from the Collaborative Perinatal Project, a multisite US study conducted from 1959 to 1974...
November 20, 2017: American Journal of Epidemiology
https://www.readbyqxmd.com/read/29165557/inverse-probability-weighted-estimation-for-monotone-and-nonmonotone-missing-data
#2
BaoLuo Sun, Neil J Perkins, Stephen R Cole, Ofer Harel, Emily Mitchell, Enrique F Schisterman, Eric J Tchetgen Tchetgen
Missing data is of common occurrence in epidemiologic research. In this paper, three data sets with induced missing values from the Collaborative Perinatal Project, a multisite United States study conducted from 1959 to 1974, are provided as examples of prototypical epidemiologic studies with missing data. Our goal is to estimate the effect of maternal smoking behavior on spontaneous abortion while adjusting for numerous confounders. At the same time, we do not necessarily wish to evaluate the joint distribution among potentially unobserved covariates, which is seldom the subject of substantive scientific interest...
November 20, 2017: American Journal of Epidemiology
https://www.readbyqxmd.com/read/29165547/multiple-imputation-for-incomplete-data-in-epidemiologic-studies
#3
Ofer Harel, Emily M Mitchell, Neil J Perkins, Stephen R Cole, Eric J Tchetgen Tchetgen, BaoLuo Sun, Enrique F Schisterman
Epidemiologic studies are frequently susceptible to missing information. Omitting observations with missing variables remains a common strategy in epidemiologic studies, yet this simple approach can often severely bias parameter estimates of interest if the values are not missing completely at random. Even when missingness is completely random, complete case analysis can reduce efficiency of estimated parameters, because large amounts of available data are simply tossed out with the incomplete observations...
November 20, 2017: American Journal of Epidemiology
https://www.readbyqxmd.com/read/29164179/schroth-physiotherapeutic-scoliosis-specific-exercises-for-adolescent-idiopathic-scoliosis-how-many-patients-require-treatment-to-prevent-one-deterioration-results-from-a-randomized-controlled-trial-sosort-2017-award-winner
#4
Sanja Schreiber, Eric C Parent, Doug L Hill, Douglas M Hedden, Marc J Moreau, Sarah C Southon
Background: Recent randomized controlled trials (RCTs) support using physiotherapeutic scoliosis-specific exercises (PSSE) for adolescents with idiopathic scoliosis (AIS). All RCTs reported statistically significant results favouring PSSE but none reported on clinical significance. The number needed to treat (NNT) helps determine if RCT results are clinically meaningful. The NNT is the number of patients that need to be treated to prevent one bad outcome in a given period. A low NNT suggests that a therapy has positive outcomes in most patients offered the therapy...
2017: Scoliosis and Spinal Disorders
https://www.readbyqxmd.com/read/29163635/departure-from-hardy-weinberg-equilibrium-and-genotyping-error
#5
Bowang Chen, John W Cole, Caspar Grond-Ginsbach
Objective: Departure from Hardy Weinberg Equilibrium (HWE) may occur due to a variety of causes, including purifying selection, inbreeding, population substructure, copy number variation or genotyping error. We searched for specific characteristics of HWE-departure due to genotyping error. Methods: Genotypes of a random set of genetic variants were obtained from the Exome Aggregation Consortium (ExAC) database. Variants with <80% successful genotypes or with minor allele frequency (MAF) <1% were excluded...
2017: Frontiers in Genetics
https://www.readbyqxmd.com/read/29161458/proton-pump-inhibitors-for-functional-dyspepsia
#6
REVIEW
Maria Ines Pinto-Sanchez, Yuhong Yuan, Ahmed Hassan, Premysl Bercik, Paul Moayyedi
BACKGROUND: Functional dyspepsia (FD or non-ulcer dyspepsia) is defined as continuous or frequently recurring epigastric pain or discomfort for which no organic cause can be found. Acid suppressive therapy, including proton pump inhibitors (PPIs), has been proposed as a therapeutic option in FD, but its efficacy remains controversial. While PPIs are generally considered safe and well tolerated, they have been associated with adverse events, especially in the long term. For this reason, decisions on whether to initiate or continue PPI therapy should be made based on an appropriate clinical indication...
November 21, 2017: Cochrane Database of Systematic Reviews
https://www.readbyqxmd.com/read/29155436/enzyme-replacement-therapy-for-infantile-onset-pompe-disease
#7
REVIEW
Min Chen, Lingli Zhang, Shuyan Quan
BACKGROUND: Infantile-onset Pompe disease is a rare and progressive autosomal-recessive disorder caused by a deficiency of the lysosomal enzyme acid alpha-glucosidase (GAA). Current treatment involves enzyme replacement therapy (with recombinant human alglucosidase alfa) and symptomatic therapies (e.g. to control secretions). Children who are cross-reactive immunological material (CRIM)-negative require immunomodulation prior to commencing enzyme replacement therapy.Enzyme replacement therapy was developed as the most promising therapeutic approach for Pompe disease; however, the evidence is lacking, especially regarding the optimal dose and dose frequency...
November 20, 2017: Cochrane Database of Systematic Reviews
https://www.readbyqxmd.com/read/29146662/comparative-effectiveness-of-injectable-penicillin-versus-a-combination-of-penicillin-and-gentamicin-in-children-with-pneumonia-characterised-by-indrawing-in-kenya-a-retrospective-observational-study
#8
Lucas Malla, Rafael Perera-Salazar, Emily McFadden, Mike English
OBJECTIVES: Kenyan guidelines for antibiotic treatment of pneumonia recommended treatment of pneumonia characterised by indrawing with injectable penicillin alone in inpatient settings until early 2016. At this point, they were revised becoming consistent with WHO guidance after results of a Kenyan trial provided further evidence of equivalence of oral amoxicillin and injectable penicillin. This change also made possible use of oral amoxicillin for outpatient treatment in this patient group...
November 15, 2017: BMJ Open
https://www.readbyqxmd.com/read/29145993/an-absorbable-hydrogel-spray-reduces-postoperative-mediastinal-adhesions-after-congenital-heart-surgery
#9
Nahidh Hasaniya, Anees Razzouk, Jennifer Newcombe, Dana Hassneiah, Jessica Heimes, Joshua Gysbers, Timothy Martens, Leonard Bailey
BACKGROUND: Adhesions encountered during reoperative cardiac surgery can prolong operative time and increase operative risk. The purpose of this clinical study was to investigate the antiadhesion property of a synthetic bioabsorbable polymer spray after cardiac reoperations in infants. METHODS: A prospective randomized double-blinded study was designed. Forty infants requiring staged cardiac operations were randomly allocated to a study group (n = 20) or a control group (n = 20)...
November 14, 2017: Annals of Thoracic Surgery
https://www.readbyqxmd.com/read/29145583/association-between-the-severity-of-diabetic-retinopathy-and-falls-in-an-asian-population-with-diabetes-the-singapore-epidemiology-of-eye-diseases-study
#10
Preeti Gupta, Amudha Aravindhan, Alfred T L Gan, Ryan E K Man, Eva K Fenwick, Paul Mitchell, Nicholas Tan, Charumathi Sabanayagam, Tien Yin Wong, Ching-Yu Cheng, Ecosse L Lamoureux
Importance: The presence and severity of diabetic retinopathy (DR) may contribute to the risk of falling in persons with diabetes, but evidence is currently equivocal. Objective: To investigate the associations of diabetes and DR severity with the likelihood of falls in a multiethnic Asian population. Design, Setting, and Participants: Cross-sectional post hoc analysis of the Singapore Epidemiology of Eye Diseases study, a population-based study of participants from 3 ethnic groups (3280 Malay, 3400 Indian, and 3353 Chinese individuals) conducted from 2004 to 2011...
November 16, 2017: JAMA Ophthalmology
https://www.readbyqxmd.com/read/29143388/in-vitro-assessment-of-retention-and-resistance-failure-loads-of-teeth-restored-with-a-complete-coverage-restoration-and-different-core-materials
#11
Vasileia Tsiagali, Yvoni Kirmanidou, Argirios Pissiotis, Konstantinos Michalakis
PURPOSE: To investigate in vitro the retention and the resistance form, as well as the failure modes of maxillary premolars restored with cast metal crowns and different core materials. MATERIALS AND METHODS: Sixty human extracted maxillary premolars were selected according to their size and were embedded in PMMA resin blocks. After removing a part of their clinical crowns, the teeth were randomly divided into 3 groups of 20 teeth and were either left unrestored, or they were restored with amalgam or composite resin...
November 16, 2017: Journal of Prosthodontics: Official Journal of the American College of Prosthodontists
https://www.readbyqxmd.com/read/29141350/-comparison-of-different-methods-in-dealing-with-hiv-viral-load-data-with-diversified-missing-value-mechanism-on-hiv-positive-msm
#12
Z Jiang, Z Dou, W L Song, J Xu, Z Y Wu
Objective: To compare results of different methods: in organizing HIV viral load (VL) data with missing values mechanism. Methods We used software SPSS 17.0 to simulate complete and missing data with different missing value mechanism from HIV viral loading data collected from MSM in 16 cities in China in 2013. Maximum Likelihood Methods Using the Expectation and Maximization Algorithm (EM), regressive method, mean imputation, delete method, and Markov Chain Monte Carlo (MCMC) were used to supplement missing data respectively...
November 10, 2017: Zhonghua Liu Xing Bing Xue za Zhi, Zhonghua Liuxingbingxue Zazhi
https://www.readbyqxmd.com/read/29140818/drop-instillation-and-glaucoma
#13
Scott A Davis, Betsy Sleath, Delesha M Carpenter, Susan J Blalock, Kelly W Muir, Donald L Budenz
PURPOSE OF REVIEW: To describe the current state of knowledge regarding glaucoma patients' eye drop technique, interventions attempting to improve eye drop technique, and methods for assessing eye drop technique. RECENT FINDINGS: In observational studies, between 18.2 and 80% of patients contaminate their eye drop bottle by touching their eye or face, 11.3-60.6% do not instill exactly one drop, and 6.8-37.3% miss the eye with the drop. Factors significantly associated with poorer technique include older age, lack of instruction on eye drop technique, female sex, arthritis, more severe visual field defect, lack of positive reinforcement to take eye drops, lower educational level, low self-efficacy, and being seen at a clinic rather than a private practice...
November 14, 2017: Current Opinion in Ophthalmology
https://www.readbyqxmd.com/read/29139110/unconditional-cash-transfers-for-reducing-poverty-and-vulnerabilities-effect-on-use-of-health-services-and-health-outcomes-in-low-and-middle-income-countries
#14
REVIEW
Frank Pega, Sze Yan Liu, Stefan Walter, Roman Pabayo, Ruhi Saith, Stefan K Lhachimi
BACKGROUND: Unconditional cash transfers (UCTs; provided without obligation) for reducing poverty and vulnerabilities (e.g. orphanhood, old age or HIV infection) are a type of social protection intervention that addresses a key social determinant of health (income) in low- and middle-income countries (LMICs). The relative effectiveness of UCTs compared with conditional cash transfers (CCTs; provided so long as the recipient engages in prescribed behaviours such as using a health service or attending school) is unknown...
November 15, 2017: Cochrane Database of Systematic Reviews
https://www.readbyqxmd.com/read/29138794/noninvasive-cardiac-testing-vs-clinical-evaluation-alone-in-acute-chest-pain-a-secondary-analysis-of-the-romicat-ii-randomized-clinical-trial
#15
Samuel W Reinhardt, Chien-Jung Lin, Eric Novak, David L Brown
Importance: The incremental benefit of noninvasive testing in addition to clinical evaluation (history, physical examination, an electrocardiogram [ECG], and biomarker assessment) vs clinical evaluation alone for patients who present to the emergency department (ED) with acute chest pain is unknown. Objective: To examine differences in outcomes with clinical evaluation and noninvasive testing (coronary computed tomographic angiography [CCTA] or stress testing) vs clinical evaluation alone...
November 14, 2017: JAMA Internal Medicine
https://www.readbyqxmd.com/read/29137560/randomized-trial-of-interventions-for-smoking-cessation-among-medicaid-beneficiaries-with-mental-illness
#16
Mary F Brunette, Sarah I Pratt, Stephen J Bartels, Emily A Scherer, Stacey C Sigmon, Joelle C Ferron, Meghan Santos, Gail E Williams, Samuel Kosydar, Rosemarie S Wolfe, Doris Lotz, Kelley Capuchino
OBJECTIVE: Medicaid beneficiaries with severe mental illnesses are a financially disadvantaged group with high rates of smoking and poor cessation outcomes. This study examined whether abstinence-contingent monetary incentives improved outcomes when added to cessation treatments at community mental health centers: prescriber visit for pharmacotherapy only (PV only), prescriber visit and facilitated quitline (PV+Q), and prescriber visit and telephone cognitive-behavioral therapy (PV+CBT)...
November 15, 2017: Psychiatric Services: a Journal of the American Psychiatric Association
https://www.readbyqxmd.com/read/29136037/safety-pharmacokinetics-and-immunological-activities-of-multiple-intravenous-or-subcutaneous-doses-of-an-anti-hiv-monoclonal-antibody-vrc01-administered-to-hiv-uninfected-adults-results-of-a-phase-1-randomized-trial
#17
Kenneth H Mayer, Kelly E Seaton, Yunda Huang, Nicole Grunenberg, Abby Isaacs, Mary Allen, Julie E Ledgerwood, Ian Frank, Magdalena E Sobieszczyk, Lindsey R Baden, Benigno Rodriguez, Hong Van Tieu, Georgia D Tomaras, Aaron Deal, Derrick Goodman, Robert T Bailer, Guido Ferrari, Ryan Jensen, John Hural, Barney S Graham, John R Mascola, Lawrence Corey, David C Montefiori
BACKGROUND: VRC01 is an HIV-1 CD4 binding site broadly neutralizing antibody (bnAb) that is active against a broad range of HIV-1 primary isolates in vitro and protects against simian-human immunodeficiency virus (SHIV) when delivered parenterally to nonhuman primates. It has been shown to be safe and well tolerated after short-term administration in humans; however, its clinical and functional activity after longer-term administration has not been previously assessed. METHODS AND FINDINGS: HIV Vaccine Trials Network (HVTN) 104 was designed to evaluate the safety and tolerability of multiple doses of VRC01 administered either subcutaneously or by intravenous (IV) infusion and to assess the pharmacokinetics and in vitro immunologic activity of the different dosing regimens...
November 2017: PLoS Medicine
https://www.readbyqxmd.com/read/29133282/effectiveness-of-a-web-2-0-intervention-to-increase-physical-activity-in-real-world-settings-randomized-ecological-trial
#18
Corneel Vandelanotte, Gregory S Kolt, Cristina M Caperchione, Trevor N Savage, Richard R Rosenkranz, Anthony J Maeder, Anetta Van Itallie, Rhys Tague, Christopher Oldmeadow, W Kerry Mummery, Mitch J Duncan
BACKGROUND: The translation of Web-based physical activity intervention research into the real world is lacking and becoming increasingly important. OBJECTIVE: To compare usage and effectiveness, in real-world settings, of a traditional Web 1.0 Web-based physical activity intervention, providing limited interactivity, to a Web 2.0 Web-based physical activity intervention that includes interactive features, such as social networking (ie, status updates, online "friends," and personalized profile pages), blogs, and Google Maps mash-ups...
November 13, 2017: Journal of Medical Internet Research
https://www.readbyqxmd.com/read/29132626/early-hospital-mortality-prediction-of-intensive-care-unit-patients-using-an-ensemble-learning-approach
#19
Aya Awad, Mohamed Bader-El-Den, James McNicholas, Jim Briggs
BACKGROUND: Mortality prediction of hospitalized patients is an important problem. Over the past few decades, several severity scoring systems and machine learning mortality prediction models have been developed for predicting hospital mortality. By contrast, early mortality prediction for intensive care unit patients remains an open challenge. Most research has focused on severity of illness scoring systems or data mining (DM) models designed for risk estimation at least 24 or 48h after ICU admission...
December 2017: International Journal of Medical Informatics
https://www.readbyqxmd.com/read/29132613/identification-and-management-of-shigella-infection-in-children-with-diarrhoea-a-systematic-review-and-meta-analysis
#20
Kirkby D Tickell, Rebecca L Brander, Hannah E Atlas, Jeffrey M Pernica, Judd L Walson, Patricia B Pavlinac
BACKGROUND: Shigella infections are a leading cause of diarrhoeal death among children in low-income and middle-income countries. WHO guidelines reserve antibiotics for treating children with dysentery. Reliance on dysentery for identification and management of Shigella infection might miss an opportunity to reduce Shigella-associated morbidity and mortality. We aimed to systematically review and evaluate Shigella-associated and dysentery-associated mortality, the diagnostic value of dysentery for the identification of Shigella infection, and the efficacy of antibiotics for children with Shigella or dysentery, or both...
December 2017: Lancet Global Health
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