Learning How and Learning What: Effects of Tacit and Codified Knowledge on Performance Improvement Following Technology Adoption

This paper examines effects of tacit and codified knowledge on performance improvement as organizations gain experience with a new technology. We draw from knowledge management and learning curve research to predict improvement rate heterogeneity across organizations. We first note that the same technology can present opportunities for improvement along more than one dimension, such as efficiency and breadth of use. We compare improvement for two dimensions: one in which the acquisition of codified knowledge leads to improvement and another in which improvement requires tacit knowledge. We hypothesize that improvement rates across organizations will be more heterogeneous for dimensions of performance that rely on tacit knowledge than for those that rely on codified knowledge (H1), and that group membership stability predicts improvement rates for dimensions relying on tacit knowledge (H2). We further hypothesize that when performance relies on codified knowledge, later adopters should improve more quickly than earlier adopters (H3). All three hypotheses are supported in a study of 15 hospitals learning to use a new surgical technology. Implications for theory and practice are discussed.     

Effects of beverage-specific alcohol consumption on drinking behaviors among urban youth

Alcoholic beverage consumption among high school students has shifted from beer to liquor. The current longitudinal study examined the effects of beverage-specific alcohol use on drinking behaviors among urban youth. Data included 731 adolescents who participated in Project Northland Chicago and reported consuming alcohol in 7th grade. Logistic regression tested the effects of beverage-specific use on consequences (e.g., alcohol use in the past month, week, heavy drinking, and ever drunkenness). Compared to wine users, adolescents who reported drinking hard liquor during their last drinking occasion had increased odds of alcohol use during the past month (OR = 1.44; 95% CI = 1.01-2.05), past week (OR = 3.37; 95% CI = 1.39-8.18), and ever drunkenness (OR = 1.56; 95% CI = 1.07-2.29). Use of hard liquor was associated with increased risk of alcohol-related consequences. Early selection of certain alcoholic beverages (e.g., hard liquor) may result in negative health outcomes and problematic alcohol use over time.     

Forensic, cultural, and systems issues in child sexual abuse cases--part 2: research and practitioner issues

This article introduces the second issue of the special double issue focusing on forensic, cultural, and systems issues in child sexual abuse cases. We briefly review the articles, which include a discussion of child sexual abuse myths, an empirical analysis of extended child sexual abuse evaluations, an article on the role of the medical provider in child sexual abuse evaluations, a study of satisfaction levels with multidisciplinary teams in child advocacy centers, and a commentary advocating for the credentialing of forensic interviewers. We call for further empirical examination of media related to child sexual abuse risk, research on appropriate models for extended sexual abuse interviews and evaluations, and optimal practices relevant to each member of multidisciplinary teams in a child advocacy center.     

Designing a non-inferiority study in kidney transplantation: a case study

In organ transplantation, placebo-controlled clinical trials are not possible for ethical reasons, and hence non-inferiority trials are used to evaluate new drugs. Patients with a transplanted kidney typically receive three to four immunosuppressant drugs to prevent organ rejection. In the described case of a non-inferiority trial for one of these immunosuppressants, the dose is changed, and another is replaced by an investigational drug. This test regimen is compared with the active control regimen. Justification for the non-inferiority margin is challenging as the putative placebo has never been studied in a clinical trial. We propose the use of a random-effect meta-regression, where each immunosuppressant component of the regimen enters as a covariate. This allows us to make inference on the difference between the putative placebo and the active control. From this, various methods can then be used to derive the non-inferiority margin. A hybrid of the 95/95 and synthesis approach is suggested. Data from 51 trials with a total of 17,002 patients were used in the meta-regression. Our approach was motivated by a recent large confirmatory trial in kidney transplantation. The results and the methodological documents of this evaluation were submitted to the Food and Drug Administration. The Food and Drug Administration accepted our proposed non-inferiority margin and our rationale.     

Design and analysis considerations for comparing dynamic treatment regimens with binary outcomes from sequential multiple assignment randomized trials

In behavioral, educational and medical practice, interventions are often personalized over time using strategies that are based on individual behaviors and characteristics and changes in symptoms, severity, or adherence that are a result of one's treatment. Such strategies that more closely mimic real practice, are known as dynamic treatment regimens (DTRs). A sequential multiple assignment randomized trial (SMART) is a multi-stage trial design that can be used to construct effective DTRs. This article reviews a simple to use ‘weighted and replicated’ estimation technique for comparing DTRs embedded in a SMART design using logistic regression for a binary, end-of-study outcome variable. Based on a Wald test that compares two embedded DTRs of interest from the ‘weighted and replicated’ regression model, a sample size calculation is presented with a corresponding user-friendly applet to aid in the process of designing a SMART. The analytic models and sample size calculations are presented for three of the more commonly used two-stage SMART designs. Simulations for the sample size calculation show the empirical power reaches expected levels. A data analysis example with corresponding code is presented in the appendix using data from a SMART developing an effective DTR in autism.     

On the mean L1-error in the heteroscedastic deconvolution problem with compactly supported noises

We study the heteroscedastic deconvolution problem when random noises have compactly supported densities. In this context, the Fourier transforms of the densities can vanish on the real line. We propose a truncated type of estimator for target density and derive the convergence rate of the mean L¹-error uniformly over a class of target densities. A lower bound for the mean L¹-error is also established. Some simulations will be given to illustrate the performance of the proposed estimator.     

Improving the Mental Health Outcomes of LGBTQ Youth and Young Adults: A Longitudinal Study

ABSTRACT

The purpose of this groundbreaking study was to evaluate outcomes of 482 LGBTQ (lesbian, gay, bisexual, transgender, or questioning) youth and young adults who received services and supports through the Comprehensive Community Mental Health Services for Children with Serious Emotional Disturbances Program (CMHI). This study was a secondary data analysis using data from a larger study of 3208 LGBTQ and non-LGBTQ youth ages 11 through 21 who had a serious emotional disturbance (SED). This study is significant in that it evaluates functional outcomes for young people identified as LGBTQ based on a specialized service framework (i.e., system of care approach). In essence, do LGBTQ youth with SED benefit from a specific approach to intervention? In addition, a comparison at intake on suicidality, bullying and victimization was conducted between the LGBTQ and non-LGBTQ identifying youth from the larger sample. The youth and a caregiver were interviewed face-to-face separately at intake, 6-months, and 12-months. Significant improvements were found across all of the dependent variables, supporting the viability of SOC for improving outcomes for LGBTQ youth. Future research should continue to build on this study by adding to the design a control group to improve internal validity of the findings.     

Statistical inference and visualization in scale-space for spatially dependent images

SiZer (SIgnificant ZERo crossing of the derivatives) is a graphical scale-space visualization tool that allows for statistical inferences. In this paper we develop a spatial SiZer for finding significant features and conducting goodness-of-fit tests for spatially dependent images. The spatial SiZer utilizes a family of kernel estimates of the image and provides not only exploratory data analysis but also statistical inference with spatial correlation taken into account. It is also capable of comparing the observed image with a specific null model being tested by adjusting the statistical inference using an assumed covariance structure. Pixel locations having statistically significant differences between the image and a given null model are highlighted by arrows. The spatial SiZer is compared with the existing independent SiZer via the analysis of simulated data with and without signal on both planar and spherical domains. We apply the spatial SiZer method to the decadal temperature change over some regions of the Earth.     

University Presidents’ Perceptions and Practice Regarding the Carrying of Concealed Handguns on College Campuses

Abstract

Objective: To assess the perceptions and practices of a national sample of college and university presidents regarding their support for concealed handguns being carried on college campuses. Participants: The sample for this study consisted of a national random sample of 900 college or university presidents. Methods: In the spring of 2013, a 3-wave mailing procedure was used to ensure an adequate response rate to a valid and reliable questionnaire. Results: The response rate was 46%, more than what was needed based on the power analysis. The vast majority (95%) of respondents were not supportive of carrying concealed handguns on campuses. They perceived there to be more disadvantages than advantages to handguns on campus. However, college administrators were not focused enough on the primary prevention of campus firearm trauma. Conclusions: The findings of this study suggest a number of activities that could be implemented to enhance safety on college and university campuses.     

Energy Drinks,Weight Loss,and Disordered Eating Behaviors

Abstract

Objective: The present study examined energy drink consumption and relations with weight loss attempts and behaviors, body image, and eating disorders. Participants/Methods: This is a secondary analysis using data from 856 undergraduate students who completed the American College Health Association–National College Health Assessment II confidentially online during February 2012. Results: This study revealed that the majority reported lifetime consumption of energy drinks (68.4%) and a substantial minority (30.2%) reported past-30-day consumption. Chi-square and t test results suggest that consumption is associated with concerns about personal appearance, weight loss attempts, and disordered eating behaviors (eg, vomiting). Hierarchical logistic regressions revealed that after controlling for demographics, the relations between energy drink consumption and the act of trying to lose weight, the use of diet pills, and the use of vomiting/laxatives remained significant. Conclusions: The current findings suggest that energy drink consumption is associated with weight loss attempts, poor body image, and unhealthy weight loss behaviors. Future research should examine the prevalence of energy drink consumption for the purpose of weight loss.