University of Nebraska Omaha

About: University of Nebraska Omaha is a education organization based out in Omaha, Nebraska, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 4526 authors who have published 8905 publications receiving 213914 citations. The organization is also known as: UNO & University of Omaha.

Specifying formative constructs in information systems research

Abstract: While researchers go to great lengths to justify and prove theoretical links between constructs, the relationship between measurement items and constructs is often ignored. By default, the relationship between construct and item is assumed to be reflective, meaning that the measurement items are a reflection of the construct. Many times, though, the nature of the construct is not reflective, but rather formative. Formative constructs occur when the items describe and define the construct rather than vice versa. In this research, we examine whether formative constructs are indeed being mistaken for reflective constructs by information systems researchers. By examining complete volumes of MIS Quarterly and Information Systems Research over the last 3 years, we discovered that a significant number of articles have indeed misspecified formative constructs. For scientific results to be valid, we argue that researchers must properly specify formative constructs. This paper discusses the implications of different patterns of common misspecifications of formative constructs on both Type I and Type II errors. To avoid these errors, the paper provides a roadmap to researchers to properly specify formative constructs. We also discuss how to address formative constructs within a research model after they are specified.

Results of a Prospective Study of Acute Liver Failure at 17 Tertiary Care Centers in the United States

Abstract: Acetaminophen overdose and idiosyncratic drug reactions have replaced viral hepatitis as the most frequent causes of acute liver failure. The cause of liver failure and coma grade at admission were...

2012 Update of the 2008 American College of Rheumatology recommendations for the use of disease-modifying antirheumatic drugs and biologic agents in the treatment of rheumatoid arthritis

Abstract: The American College of Rheumatology (ACR) most recently published recommendations for use of disease modifying anti-rheumatic drugs (DMARDs) and biologics in the treatment of rheumatoid arthritis (RA) in 2008 (1). These recommendations covered indications for use, monitoring of side-effects, assessment of the clinical response to DMARDs and biologics, screening for tuberculosis (TB), and assessment of the roles of cost and patient preference in decision-making for biologic agents (1). Recognizing the rapidly evolving knowledge in RA management and the accumulation of new evidence regarding the safety and efficacy of existing and newer therapies, the ACR commissioned an update of the 2008 recommendations in select topic areas. The 2012 revision updates the 2008 ACR recommendations in the following areas: (1) indications for DMARDs and biologics; (2) switching between DMARD and biologic therapies; (3) use of biologics in high-risk patients (those with hepatitis, congestive heart failure, and malignancy); (4) screening for TB in patients starting or currently receiving biologics; and (5) vaccination in patients starting or currently receiving DMARDs or biologics (Table 1). Table 1 Overview Comparison of Topics and Medications Included in the 2008 and 2012 ACR RA Recommendations METHODS We utilized the same methodology as described in detail in the 2008 guidelines (1) to maintain consistency and to allow cumulative evidence to inform this 2012 recommendation update. These recommendations were developed by two expert panels: (1) a non-voting working group and Core Expert Panel (CEP) of clinicians and methodologists responsible for the selection of the relevant topic areas to be considered, the systematic literature review, and the evidence synthesis and creation of “clinical scenarios”; and (2) a Task Force Panel (TFP) of 11 internationally-recognized expert clinicians, patient representatives and methodologists with expertise in RA treatment, evidence-based medicine and patient preferences who were tasked with rating the scenarios created using an ordinal scale specified in the Research and Development/University of California at Los Angeles (RAND/UCLA) Appropriateness method (2–4). This method solicited formal input from a multi-disciplinary TFP panel to make recommendations informed by the evidence. The methods used to develop the updated ACR recommendations are described briefly below. Systematic Literature Review – Sources, Databases and Domains Literature searches for both DMARDs and biologics relied predominantly on PubMed searches) with medical subject headings (MeSH) and relevant keywords similar to those used for the 2008 ACR RA recommendations (see Appendices 1 and 2). We included randomized clinical trials (RCTs), controlled clinical trials (CCTs), quasi-experimental designs, cohort studies (prospective or retrospective), and case-control studies, with no restrictions on sample size. More details about inclusion criteria are listed below and in Appendix 3. The 2008 recommendations were based on a literature search that ended on February 14, 2007. The literature search end date for the 2012 Update was February 26, 2010 for the efficacy and safety studies and September 22, 2010 for additional qualitative reviews related to TB screening, immunization and hepatitis (similar to the 2008 methodology). Studies published subsequent to that date were not included. For biologics, we also reviewed the Cochrane systematic reviews and overviews (published and in press) in the Cochrane Database of Systematic Reviews to identify additional studies (5–8) and further supplemented by hand-checking the bibliographies of all included articles. Finally, the CEP and TFP confirmed that relevant literature was included for evidence synthesis. Unless they were identified by the literature search and met the article inclusion criteria (see Appendix 3), we did not review any unpublished data from product manufacturers, investigators, or the Food and Drug Administration (FDA) Adverse Event Reporting System. We searched the literature for the eight DMARDs and nine biologics most commonly used for the treatment of RA. Literature was searched for eight DMARDS including azathioprine, cyclosporine, hydroxychloroquine, leflunomide, methotrexate, minocycline, organic gold compounds and sulfasalazine. As in 2008, azathioprine, cyclosporine and gold were not included in the recommendations based on infrequent use and lack of new data (Table 1). Literature was searched for nine biologics including abatacept, adalimumab, anakinra, certolizumab pegol, etanercept, golimumab, infliximab, rituximab and tocilizumab; anakinra was not included in the recommendations due to infrequent use and lack of new data. Details of the bibliographic search strategy are listed in Appendix 1.

American College of Rheumatology 2008 Recommendations for the Use of Nonbiologic and Biologic Disease-Modifying Antirheumatic Drugs in Rheumatoid Arthritis

Abstract: Guidelines and recommendations developed and/or endorsed by the American College of Rheumatology (ACR) are intended to provide guidance for particular patterns of practice and not to dictate the care of a particular patient. The ACR considers adherence to these guidelines and recommendations to be voluntary, with the ultimate determination regarding their application to be made by the physician in light of each patient’s individual circumstances. Guidelines and recommendations are intended to promote beneficial or desirable outcomes but cannot guarantee any specific outcome. Guidelines and recommendations developed or endorsed by the ACR are subject to periodic revision as warranted by the evolution of medical knowledge, technology, and practice.

Screening and Surveillance for the Early Detection of Colorectal Cancer and Adenomatous Polyps, 2008: A Joint Guideline from the American Cancer Society, the US Multi‐Society Task Force on Colorectal Cancer, and the American College of Radiology*†

Abstract: In the United States, colorectal cancer (CRC) is the third most common cancer diagnosed among men and women and the second leading cause of death from cancer CRC largely can be prevented by the detection and removal of adenomatous polyps, and survival is significantly better when CRC is diagnosed while still localized In 2006 to 2007, the American Cancer Society, the US Multi Society Task Force on Colorectal Cancer, and the American College of Radiology came together to develop consensus guidelines for the detection of adenomatous polyps and CRC in asymptomatic average-risk adults In this update of each organization's guidelines, screening tests are grouped into those that primarily detect cancer early and those that can detect cancer early and also can detect adenomatous polyps, thus providing a greater potential for prevention through polypectomy When possible, clinicians should make patients aware of the full range of screening options, but at a minimum they should be prepared to offer patients a choice between a screening test that is effective at both early cancer detection and cancer prevention through the detection and removal of polyps and a screening test that primarily is effective at early cancer detection It is the strong opinion of these 3 organizations that colon cancer prevention should be the primary goal of screening