Biostatistics Commons^™

Constructing A Confidence Interval For The Fraction Who Benefit From Treatment, Using Randomized Trial Data, Emily J. Huang, Ethan X. Fang, Daniel F. Hanley, Michael Rosenblum

Johns Hopkins University, Dept. of Biostatistics Working Papers

The fraction who benefit from treatment is the proportion of patients whose potential outcome under treatment is better than that under control. Inference on this parameter is challenging since it is only partially identifiable, even in our context of a randomized trial. We propose a new method for constructing a confidence interval for the fraction, when the outcome is ordinal or binary. Our confidence interval procedure is pointwise consistent. It does not require any assumptions about the joint distribution of the potential outcomes, although it has the flexibility to incorporate various user-defined assumptions. Unlike existing confidence interval methods for partially …

Persistent Organic Pollutants And Mortality In The United States, Nhanes 1999-2011., Kristiann Fry, Melinda C Power

Epidemiology Faculty Publications

Background

Persistent organic pollutants (POPs) are environmentally and biologically persistent chemicals that include polybrominated diphenyl ethers (PBDEs), per- and polyfluoroalkyl substances (PFASs), polychlorinated biphenyls (PCBs), and organochlorine (OC) pesticides. Currently, data on the associations between exposure to POPs and the risk of mortality in the U.S. population is limited.

Our objective was to determine if higher exposure to POPs is associated with greater risk of all-cause, cancer, heart/cerebrovascular disease, or other-cause mortality.

Methods

Analyses included participants aged 60 years and older from the 1999–2006 National Health and Nutrition Examination Surveys (NHANES). We included 483 participants for analyses of PBDEs, 1043 …

Increased Birth Weight Is Associated With Altered Gene Expression In Neonatal Foreskin, Leryn J. Reynolds, Rebecca I. Pollack, Richard J. Charnigo, Cetewayo S. Rashid, Arnold J. Stromberg, Shu Shen, John O'Brien, Kevin J. Pearson

Pharmacology and Nutritional Sciences Faculty Publications

Elevated birth weight is linked to glucose intolerance and obesity health-related complications later in life. No studies have examined if infant birth weight is associated with gene expression markers of obesity and inflammation in a tissue that comes directly from the infant following birth. We evaluated the association between birth weight and gene expression on fetal programming of obesity. Foreskin samples were collected following circumcision, and gene expression analyzed comparing the 15% greatest birth weight infants (n = 7) v. the remainder of the cohort (n = 40). Multivariate linear regression models were fit to relate expression levels on differentially …

Systems Biology Approach To Late-Onset Alzheimer's Disease Genome-Wide Association Study Identifies Novel Candidate Genes Validated Using Brain Expression Data And Caenorhabditis Elegans Experiments, Shubhabrata Mukherjee, Joshua C. Russell, Daniel T. Carr, Jeremy D. Burgess, Mariet Allen, Daniel J. Serie, Kevin L. Boehme, John S. K. Kauwe, Adam C. Naj, David W. Fardo, Dennis W. Dickson, Thomas J. Montine, Nilufer Ertekin-Taner, Matt R. Kaeberlein, Paul K. Crane

Biostatistics Faculty Publications

Introduction—We sought to determine whether a systems biology approach may identify novel late-onset Alzheimer's disease (LOAD) loci.

Methods—We performed gene-wide association analyses and integrated results with human protein-protein interaction data using network analyses. We performed functional validation on novel genes using a transgenic Caenorhabditis elegans Aβ proteotoxicity model and evaluated novel genes using brain expression data from people with LOAD and other neurodegenerative conditions.

Results—We identified 13 novel candidate LOAD genes outside chromosome 19. Of those, RNA interference knockdowns of the C. elegans orthologs of UBC, NDUFS3, EGR1, and ATP5H were associated with Aβ …

Comparison Of Adaptive Randomized Trial Designs For Time-To-Event Outcomes That Expand Versus Restrict Enrollment Criteria, To Test Non-Inferiority, Josh Betz, Jon Arni Steingrimsson, Tianchen Qian, Michael Rosenblum

Johns Hopkins University, Dept. of Biostatistics Working Papers

Adaptive enrichment designs involve preplanned rules for modifying patient enrollment criteria based on data accrued in an ongoing trial. These designs may be useful when it is suspected that a subpopulation, e.g., defined by a biomarker or risk score measured at baseline, may benefit more from treatment than the complementary subpopulation. We compare two types of such designs, for the case of two subpopulations that partition the overall population. The first type starts by enrolling the subpopulation where it is suspected the new treatment is most likely to work, and then may expand inclusion criteria if there is early evidence …

Judging The Neonatal Abstinence Syndrome Assessment Tools To Guide Future Tool Development: The Use Of Clinimetrics As Opposed To Psychometrics, Philip M. Westgate, Enrique Gomez-Pomar

Biostatistics Faculty Publications

In the face of the current Neonatal Abstinence Syndrome (NAS) epidemic, there is considerable variability in the assessment and management of infants with NAS. In this manuscript, we particularly focus on NAS assessment, with special attention given to the popular Finnegan Neonatal Abstinence Score (FNAS). A major instigator of the problem of variable practices is that multiple modified versions of the FNAS exist and continue to be proposed, including shortened versions. Furthermore, the validity of such assessment tools has been questioned, and as a result, the need for better tools has been suggested. The ultimate purpose of this manuscript, therefore, …

Dietary Inflammatory Index And Colorectal Cancer Risk – A Meta-Analysis, Nitin Shivappa, Justyna Godos, James R. Hébert, Michael David Wirth, Gabriele Piuri, Attilio Speciani, Giuseppe Grosso

Faculty Publications

Diet and chronic inflammation of the colon have been suggested to be risk factors in the development of colorectal cancer (CRC). The possible link between inflammatory potential of diet, measured through the Dietary Inflammatory Index (DII®), and CRC has been investigated in several populations across the world. The aim of this study was to conduct a meta-analysis on studies exploring this association. Data from nine studies were eligible, of which five were case-control and four were cohort studies. Results from meta-analysis showed a positive association between increasing DII scores, indicating a pro-inflammatory diet, and CRC. Individuals in the highest versus …

Prevalence And Trends In Transmitted And Acquired Antiretroviral Drug Resistance, Washington, Dc, 1999-2014., Annette M Aldous, Amanda D Castel, David M Parenti

Epidemiology Faculty Publications

Background

Drug resistance limits options for antiretroviral therapy (ART) and results in poorer health outcomes among HIV-infected persons. We sought to characterize resistance patterns and to identify predictors of resistance in Washington, DC.

Methods

We analyzed resistance in the DC Cohort, a longitudinal study of HIV-infected persons in care in Washington, DC. We measured cumulative drug resistance (CDR) among participants with any genotype between 1999 and 2014 (n = 3411), transmitted drug resistance (TDR) in ART-naïve persons (n = 1503), and acquired drug resistance (ADR) in persons with genotypes before and after ART initiation (n = 309). Using logistic regression, …

Level Of Exposure Of Childhood Tuberculosis With Adult Pulmonary Tuberculosis Household Contacts, Al Asyary, Tris Eryando, Purwantyastuti Purwantyastuti, Purnawan Junadi, Carol Clark, Edwin Van Teijlingen

Kesmas

Tuberkulosis paru (TB) pada anak kian menjadi masalah kesehatan global yang masih terlupakan seiring dengan peningkatan proporsi TB di Indonesia. Penularan penyakit ini di populasi umum seringkali berdampak pada anak, terlebih ketika kontak TB terjadi di rumah tangga. Penelitian ini bertujuan untuk memperoleh faktor protektif sehingga anak tetap sehat meskipun memiliki kontak dengan penderita TB dewasa serumah. Penelitian ini dilakukan dengan pendekatan kasus kontrol pada 132 responden anak yang berasal dari delapan rumah sakit rujukan dan beberapa puskesmas di Provinsi Daerah Istimewa Yogyakarta. Penelitian dilakukan dalam periode Januari hingga Desember 2014 yang hasilnya dianalisis dengan uji bivariat (kai kuadrat) dan …

Influence Of Quality Of Work Life Towards Psychological Well-Being And Turnover Intention Of Nurses And Midwives In Hospital, Indra Wahju Hardjanti, Aryo Dewanto, Noermijati Noermijati

Kesmas

Selama ini perawat telah dilatih untuk memberikan perawatan pasien dan meningkatkan kualitas hidup pasien, namun kualitas kehidupan kerja dan psychological well-being mereka sendiri terabaikan. Rendahnya kualitas kehidupan kerja perawat di rumah sakit menyebabkan tingginya keinginan pindah kerja perawat. Tingginya angka keinginan pindah kerja perawat dan bidan di Rumah Sakit X Malang merupakan masalah yang memerlukan perhatian dari manajemen rumah sakit agar tidak menjadi menyebabkan rendahnya mutu pelayanan kesehatan di rumah sakit. Penelitian ini bertujuan untuk mengetahui hubungan antara kualitas kehidupan kerja, psychological well-being, dan keinginan pindah kerja perawat dan bidan di rumah sakit. Penelitian ini menggunakan desain penelitian kuantitatif korelasional …

Risk Differences Between Elderly Men And Women Toward Doctor-Diagnosed Diabetes Mellitus In Urban Areas In Indonesia: 2013 National Basic Health Research Data, Meiwita Budiharsana

Kesmas

Diabetes melitus (DM) adalah salah satu penyakit tidak menular yang paling umum di Indonesia. DM disebabkan berbagai faktor risiko. Peningkatan prevalensi DM salah satunya disebabkan oleh perubahan gaya hidup di perkotaan. Penelitian ini bertujuan untuk menguji perbedaan prevalensi DM yang didiagnosis dokter pada laki-laki dan perempuan usia 15 tahun keatas yang tinggal di daerah perkotaan di Indonesia. Analisis menggunakan data sekunder Riset Kesehatan Dasar (Riskesdas) 2013 dengan desain studi potong lintang. Total sampel sebanyak 333.731 responden. Metode analisis menggunakan regresi logistik ganda. Hasil menunjukkan bahwa DM yang didiagnosis dokter pada laki-laki dan perempuan usia 15-39 tahun di perkotaan tidak berbeda. …

Bancroftian Filariasis Transmission Parameters After The Fifth Year Of Filiariasis Mass Drug Administration In Pekalongan City, Tutik Ida Rosanti, Sugeng Juwono Mardihusodo, Wayan Artama

Kesmas

Penelitian ini bertujuan untuk mengukur parameter parasitologi (microfilaria rate, kepadatan mikrofilaria), parameter imunologi (antigen prevalence) dan parameter entomologi (infection rate dan infective rate) pada tahun kelima pelaksanaan mass drug administration di Kelurahan Pabean Kota Pekalongan. Penelitian ini merupakan penelitian observasional dengan pendekatan potong lintang yang dilaksanakan pada bulan Juli sampai dengan Agustus 2015 di Kelurahan Pabean Kota Pekalongan. Microfilaria rate dan kepadatan mikrofilaria ditentukan dengan pemeriksaan darah jari pada 313 responden. Antigen prevalence ditentukan dengan mengukur antigen beredar menggunakan metode immunochromatographic test (ICT) Wuchereria bancrofti. Incective rate dan infection rate diukur dengan cara menemukan larva cacing filaria pada nyamuk hasil …

Influence Of Scaling Up Nutrition Education Towards Knowledge And Attitude Of Students At Santa Elisabeth Medan School Of Health Sciences, Rani Gartika Holivia Silalahi, Yesschi Anggraeni Tambunan

Kesmas

Tingginya angka pernikahan pada usia remaja yang disertai dengan rendahnya pengetahuan tentang pola asuh merupakan salah satu pemicu terjadinya masalah gizi. Remaja merupakan orang tua masa depan. Tujuan penelitian ini untuk mengetahui pengaruh pendidikan 1.000 hari pertama kehidupan terhadap pengetahuan dan sikap mahasiswi Sekolah Tinggi Ilmu Kesehatan Santa Elisabeth Medan tahun 2016. Penelitian ini menggunakan kuasi eksperimental dengan desain one group pre- dan post test. Metode pengambilan sampel dengan metode purposive sampling sebanyak 115 mahasiswi tingkat III program studi Diploma III Kebidanan. Pendidikan dilakukan di kelas sebanyak 4 kali dalam 2 minggu dengan menggunakan metode mengajar dan diskusi. Penelitian ini …

Provision Of Informed Consent Towards The Level Of Anxiety In Pre-Operative Patients At Mamuju District Public Hospital, Imelda Appulembang

Kesmas

Tindakan pembedahan merupakan salah satu tindakan medis yang dapat mendatangkan stressor sehingga menimbulkan kecemasan pada pasien. Penelitian ini bertujuan untuk mengetahui pengaruh pemberian informed consent terhadap tingkat kecemasan pada pasien pra-operasi di Rumah Sakit Umum Daerah (RSUD) Mamuju. Populasi pada penelitian ini adalah pasien pra-operasi. Sampel ditentukan dengan menggunakan pendekatan accidental sampling sehingga diperoleh sampel sebanyak 32 orang. Jenis penelitian ini adalah penelitian kuantitatif dengan menggunakan metode quasi experimental design melalui pendekatan non-equivalent time sample design yang dianalisis dengan menggunakan uji statistik Wilcoxon. Hasil penelitian menunjukkan bahwa terdapat pengaruh pemberian informed consent terhadap tingkat kecemasan pasien. Dapat disimpulkan pemberian informed …

The Profile And Determinant Factors Of Quality Of Life In Patients With Diabetic Neuropathy, Rizaldy Taslim Pinzon, Kadek Sinthia Grahita Adnyana, Marta Lisnawati Zalukhu

Kesmas

Neuropati merupakan salah satu komplikasi tersering pada diabetes melitus (DM). Neuropati dapat memengaruhi kualitas hidup, derajat kesehatan, maupun tingkat ekonomi. Oleh karena itu, penting untuk mengetahui kualitas hidup pasien DM dengan neuropati beserta dampak yang ditimbulkannya terlebih dahulu agar mendapatkan penanganan yang tepat demi meningkatkan kualitas hidup pasien. Penelitian ini bertujuan untuk mengetahui profil kualitas hidup pasien DM dengan neuropati. Penelitian ini merupakan studi observasional menggunakan Short Form 8 (SF-8) Health Survey Standard Indonesia terhadap pasien diabetes melitus dengan neuropati yang diambil secara konsekutif pada bulan Maret hingga Agustus 2016 di Poli Saraf Rumah Sakit Bethesda, Yogyakarta. Terdapat 57 subjek …

Effects Of Contraceptive Use On Productivity Of Women Labor At Pt. Bomar Makassar Industrial Area, Masni Mappajanci, Andi Misnawati, Darmawansyah Darmawansyah

Kesmas

Produktivitas kerja potensial pada kelangsungan hidup perusahaan. Penggunaan kontrasepsi dapat memengaruhi fisiologi setiap perempuan, sehingga dapat memengaruhi aktivitas sehari-hari dan akan berdampak terhadap produktivitas tenaga kerja. Penelitian ini bertujuan untuk mengetahui pengaruh penggunaan alat kontrasepsi terhadap produktivitas tenaga kerja perempuan dengan mengontrol usia, pendidikan dan motivasi kerja. Penelitian dengan rancangan potong lintang melibatkan 71 pekerja perempuan PT Bomar Makassar yang telah menikah. Pengumpulan data dilakukan dengan wawancara menggunakan kuesioner pada bulan Mei sampai Juni 2015, kemudian dianalisis secara univariat, bivariat, dan multivariat. Hasil penelitian menunjukkan bahwa terdapat pengaruh penggunaan alat kontrasepsi terhadap produktivitas kerja setelah dikontrol dengan variabel usia (nilai …

Nonparametric Variable Importance Assessment Using Machine Learning Techniques, Brian D. Williamson, Peter B. Gilbert, Noah Simon, Marco Carone

UW Biostatistics Working Paper Series

In a regression setting, it is often of interest to quantify the importance of various features in predicting the response. Commonly, the variable importance measure used is determined by the regression technique employed. For this reason, practitioners often only resort to one of a few regression techniques for which a variable importance measure is naturally defined. Unfortunately, these regression techniques are often sub-optimal for predicting response. Additionally, because the variable importance measures native to different regression techniques generally have a different interpretation, comparisons across techniques can be difficult. In this work, we study a novel variable importance measure that can …

The Relationship Of Plasma Trans Fatty Acids With Dietary Inflammatory Index Among Us Adults, Mohsen Mazidi, Hong-Kai Gao, Nitin Shivappa, Michael David Wirth, James R. Hébert, Andre Pascal Kengne

Faculty Publications

Background: It has been suggested that trans fatty acids (TFAs) play an important role in cardiovascular diseases. We investigated the association between plasma TFAs and the dietary inflammatory index (DII) ™ in US adults.

Methods: National Health and Nutrition Examination Survey (NHANES) participants with data on plasma TFAs measured from 1999 to 2010 were included. Energy-adjusted-DII ™ (E-DII ™) expressed per 1000 kcal was calculated from 24-h dietary recalls. All statistical analyses accounted for the survey design and sample weights.

Results: Of the 5446 eligible participants, 46.8% (n = 2550) were men. The mean age of the population was 47.1 …

Likelihood-Based Methods For Analysis Of Copy Number Variation Using Next Generation Sequencing Data., Udika Iroshini Bandara

Electronic Theses and Dissertations

A Copy Number Variation (CNV) detection problem is considered using Circular Binary Segmentation (CBS) procedures, including newly developed procedures based on likelihood ratio tests with the parametric bootstrap for models based on discrete distributions for count data (Poisson and negative binomial) and a widely-used DNAcopy package. Results from the literature concerning maximum likelihood estimation for the negative binomial distribution are reviewed. The Newton-Raphson method is used to find the root of the derivative of the profile log likelihood function when applicable, and it is proven that this method converges to the true Maximum Likeihood Estimate (MLE), if the starting point …

Estimation Of The Three Key Parameters And The Lead Time Distribution In Lung Cancer Screening., Ruiqi Liu

Electronic Theses and Dissertations

This dissertation contains three research projects on cancer screening probability modeling. Cancer screening is the primary technique for early detection. The goal of screening is to catch the disease early before clinical symptoms appear. In these projects, the three key parameters and lead time distribution were estimated to provide a statistical point of view on the effectiveness of cancer screening programs. In the first project, cancer screening probability model was used to analyze the computed tomography (CT) scan group in the National Lung Screening Trial (NLST) data. Three key parameters were estimated using Bayesian approach and Markov Chain Monte Carlo …