Methodological Issues in Studying Treatment Effects in Patients with Cerebrovascular Disease

Evaluation of the neuropsychological effects of surgical treatment on cerebrovascular disease is beset by numerous methodological difficulties. These include problems specific to this patient population as well as others inherent in all retrospective studies. Five such problems are described: 1) nonrandomized subject selection; 2) dropout from follow-up; 3) natural history of cerebrovascular disease; 4) effects of hospitalization; and 5) the role of practice effects. This paper examines these methodological problems for their impact on our knowledge and proposes alternative research directions to address their shortcomings

Creative destruction in science

Drawing on the concept of a gale of creative destruction in a capitalistic economy, we argue that initiatives to assess the robustness of findings in the organizational literature should aim to simultaneously test competing ideas operating in the same theoretical space. In other words, replication efforts should seek not just to support or question the original findings, but also to replace them with revised, stronger theories with greater explanatory power. Achieving this will typically require adding new measures, conditions, and subject populations to research designs, in order to carry out conceptual tests of multiple theories in addition to directly replicating the original findings. To illustrate the value of the creative destruction approach for theory pruning in organizational scholarship, we describe recent replication initiatives re-examining culture and work morality, working parents\u2019 reasoning about day care options, and gender discrimination in hiring decisions. Significance statement It is becoming increasingly clear that many, if not most, published research findings across scientific fields are not readily replicable when the same method is repeated. Although extremely valuable, failed replications risk leaving a theoretical void\u2014 reducing confidence the original theoretical prediction is true, but not replacing it with positive evidence in favor of an alternative theory. We introduce the creative destruction approach to replication, which combines theory pruning methods from the field of management with emerging best practices from the open science movement, with the aim of making replications as generative as possible. In effect, we advocate for a Replication 2.0 movement in which the goal shifts from checking on the reliability of past findings to actively engaging in competitive theory testing and theory building. Scientific transparency statement The materials, code, and data for this article are posted publicly on the Open Science Framework, with links provided in the article

Prospective Randomized Trial of Two Wound Management Strategies for Dirty Abdominal Wounds

OBJECTIVE: To determine the optimal method of wound closure for dirty abdominal wounds. SUMMARY BACKGROUND DATA: The rate of wound infection for dirty abdominal wounds is approximately 40%, but the optimal method of wound closure remains controversial. Three randomized studies comparing delayed primary closure (DPC) with primary closure (PC) have not conclusively shown any advantage of one method over the other in terms of wound infection. METHODS: Fifty-one patients with dirty abdominal wounds related to perforated appendicitis, other perforated viscus, traumatic injuries more than 4 hours old, or intraabdominal abscesses were enrolled. Patients were stratified by cause (appendicitis vs. all other causes) and prospectively randomized to one of two wound management strategies: E/DPC (wound packed with saline-soaked gauze, evaluated 3 days after surgery for closure the next day if appropriate) or PC. In the E/DPC group, wounds that were not pristine when examined on postoperative day 3 were not closed and daily dressing changes were instituted. Wounds were considered infected if purulence discharged from the wound, or possibly infected if signs of inflammation or a serous discharge developed. RESULTS: Two patients were withdrawn because they died less than 72 hours after surgery. The wound infection rate was greater in the PC group than in the E/DPC group. Lengths of hospital stay and hospital charges were similar between the two groups. CONCLUSION: A strategy of DPC for appropriate dirty abdominal wounds 4 days after surgery produced a decreased wound infection rate compared with PC without increasing the length of stay or cost

A comprehensive genetic association study of Alzheimer disease in African Americans.

OBJECTIVES: To evaluate the association of genetic variation with late-onset Alzheimer disease (AD) in African Americans, including genes implicated in recent genome-wide association studies of whites. DESIGN: We analyzed a genome-wide set of 2.5 million imputed markers to evaluate the genetic basis of AD in an African American population. SUBJECTS: Five hundred thirteen well-characterized African American AD cases and 496 cognitively normal African American control subjects. SETTING: Data were collected from multiple sites as part of the Multi-Institutional Research on Alzheimer Genetic Epidemiology (MIRAGE) Study and the Henry Ford Health System as part of the Genetic and Environmental Risk Factors for Alzheimer Disease Among African Americans (GenerAAtions) Study. RESULTS: Several significant single-nucleotide polymorphisms (SNPs) were observed in the region of the apolipoprotein E gene (APOE). After adjusting for the confounding effects of APOE genotype, one of these SNPs, rs6859 in PVRL2, remained significantly associated with AD (P = .0087). Association was also observed with SNPs in CLU, PICALM, BIN1, EPHA1, MS4A, ABCA7, and CD33, although the effect direction for some SNPs and the most significant SNPs differed from findings in data sets consisting of whites. Finally, using the African American genome-wide association study data set as a discovery sample, we obtained suggestive evidence of association with SNPs for several novel candidate genes. CONCLUSIONS: Some genes contribute to AD pathogenesis in both white and African American cohorts, although it is unclear whether the causal variants are the same. A larger African American sample will be needed to confirm novel gene associations, which may be population specific