Statistical control is widely used in correlational studies with the intent of providing more accurate estimates of relationships among variables, more conservative tests of hypotheses, or ruling out ...alternative explanations for empirical findings. However, the use of control variables can produce uninterpretable parameter estimates, erroneous inferences, irreplicable results, and other barriers to scientific progress. As a result, methodologists have provided a great deal of advice regarding the use of statistical control, to the point that researchers might have difficulties sifting through and prioritizing the available suggestions. We integrate and condense this literature into a set of 10 essential recommendations that are generally applicable and which, if followed, would substantially enhance the quality of published organizational research. We provide explanations, qualifications, and examples following each recommendation.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NMLJ, NUK, OILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
We employ a novel adaptation of self-construal theory to explain the theoretical basis of factors that influence organic food purchase decisions. Study 1 reveals that egoistic (e.g., personal health) ...and altruistic (e.g., environmental) considerations simultaneously predict consumers' organic attitudes and purchase intentions. Study 2 indicates that societal considerations play a more influential role for green/organic products. Study 3 tests advertising treatments utilizing egoistic and/or altruistic claims. Results show that an ad featuring both egoistic and altruistic appeals produces more favorable responses than either an egoistic treatment or a control ad, but is equally effective as an ad featuring altruistic claims.
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BFBNIB, IZUM, KILJ, NMLJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Summary Background HSD3B1 (1245A>C) has been mechanistically linked to castration-resistant prostate cancer because it encodes an altered enzyme that augments dihydrotestosterone synthesis from ...non-gonadal precursors. We postulated that men inheriting the HSD3B1 (1245C) allele would exhibit resistance to androgen-deprivation therapy (ADT). Methods In this multicohort study, we determined HSD3B1 genotype retrospectively in men treated with ADT for post-prostatectomy biochemical failure and correlated genotype with long-term clinical outcomes. We used data and samples from prospectively maintained prostate cancer registries at the Cleveland Clinic (Cleveland, OH, USA; primary study cohort) and the Mayo Clinic (Rochester, MN, USA; post-prostatectomy and metastatic validation cohorts). In the post-prostatectomy cohorts, patients of any age were eligible if they underwent prostatectomy between Jan 1, 1996, and Dec 31, 2009 (at the Cleveland Clinic; primary cohort), or between Jan 1, 1987, and Dec 31, 2011 (at the Mayo Clinic; post-prostatectomy cohort) and were treated with ADT for biochemical failure or for non-metastatic clinical failure. In the metastatic validation cohort, patients of any age were eligible if they were enrolled at Mayo Clinic between Sept 1, 2009, and July 31, 2013, with metastatic castration-resistant prostate cancer. The primary endpoint was progression-free survival according to HSD3B1 genotype. We did prespecified multivariable analyses to assess the independent predictive value of HSD3B1 genotype on outcomes. Findings We included and genotyped 443 patients: 118 in the primary cohort (who underwent prostatectomy), 137 in the post-prostatectomy validation cohort, and 188 in the metastatic validation cohort. In the primary study cohort, median progression-free survival diminished as a function of the number of variant alleles inherited: 6·6 years (95% CI 3·8–not reached) in men with homozygous wild-type genotype, 4·1 years (3·0–5·5) in men with heterozygous variant genotype, and 2·5 years (0·7 to not reached) in men with homozygous variant genotype (p=0·011). Relative to the homozygous wild-type genotype, inheritance of two copies of the variant allele was predictive of decreased progression-free survival (hazard ratio HR 2·4 95% CI 1·1–5·3, p=0·029), as was inheritance of one copy of the variant allele (HR 1·7 1·0–2·9, p=0·041). Findings were similar for distant metastasis-free survival and overall survival. The effect of the HSD3B1 genotype was independently confirmed in the validation cohorts. Interpretation Inheritance of the HSD3B1 (1245C) allele that enhances dihydrotestosterone synthesis is associated with prostate cancer resistance to ADT. HSD3B1 could therefore potentially be a powerful genetic biomarker capable of distinguishing men who are a priori likely to fare favourably with ADT from those who harbour disease liable to behave more aggressively, and who therefore might warrant early escalated therapy. Funding Prostate Cancer Foundation, National Institutes of Health, US Department of Defense, Howard Hughes Medical Institute, American Cancer Society, Conquer Cancer Foundation of the American Society of Clinical Oncology, Cleveland Clinic Research Programs Committee and Department of Radiation Oncology, Gail and Joseph Gassner Development Funds.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
This research investigates online consumer behavior in an e-commerce context with a focus on consumer online shopping cart use and subsequent cart abandonment. A model rooted in the Uses and ...Gratifications Theory, the Unified Theory of Acceptance and Use of Technology, and the concept of the purchase funnel is developed to explain the predicted relationships. Empirical findings based on clickstream data show that returning to an existing cart increases the subsequent cart use and decreases cart abandonment. Conversely, viewing clearance pages and viewing a large number of product reviews increases both cart use and cart abandonment. Browsing product pages decreases cart use, and increases cart abandonment. The moderating role of smartphone-based shopping is also examined, with the moderating effects primarily occurring early in the purchase funnel affecting cart use, and influencing cart abandonment to a smaller degree. Theoretical contributions and managerial implications for digital marketers are provided.
Abstract In the present report we aimed to analyze the incremental value of preoperative magnetic resonance imaging (MRI), in addition to clinical variables and clinically-derived nomograms, in ...predicting outcomes radical prostatectomy (RP). All Mayo Clinic RP patients who underwent preoperative 1.5-Tesla MRI with endo-rectal coil from 2003 to 2013 were identified. Clinical and histopathological variables were used to calculate Partin estimates and Cancer of the Prostate Risk Assessment (CAPRA) score. MRI results in terms of extracapsular extension (ECE), seminal vesicle invasion (SVI), and lymph-node invasion (N+) were recorded. Using RP pathology as gold standard, we developed multivariate logistic regression models based on clinical variables, Partin Tables, and CAPRA score, and assessed their predictive accuracy before and after the addition of MRI results. Five hundred and one patients were included. MRI + clinical models outperformed clinical-based models alone for all outcomes. Comparing Partin and Partin + MRI predictive models, the areas under the curve were 0.61 versus 0.73 for ECE, 0.75 versus 0.82 for SVI, and 0.82 versus 0.85 for N+. Comparing CAPRA and CAPRA + MRI models, the areas under the curve were 0.69 versus 0.77 for ECE, 0.75 versus 0.83 for SVI, and 0.82 versus 0.85 for N+. Our data show that MRI can improve clinical-based models in prediction of nonorgan confined disease, particularly for ECE and SVI. Patient summary Magnetic resonance imaging, together with clinical information, can be useful in preoperative assessment before radical prostatectomy.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
This research sheds light on the theoretical mechanism behind consumer discounting of discounts and extends it to the online daily deals context. Based on advertising and behavioral pricing research, ...we develop and empirically test a conceptual model of the effects of discount level on consumer perceptions of discount credibility, the extent of discounting of discounts, and change in purchase intentions for online daily deal promotions as compared with price promotions offered directly by online stores. The findings offer important managerial recommendations for retailers and daily deal managers with respect to utilizing direct online price promotions and daily deal promotions.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
BACKGROUND:Adverse events after rhinoplasty vary in etiology and severity, a fact that is reflected in the current American Society of Plastic Surgeons rhinoplasty consent form. However, there is ...currently no literature providing a comprehensive summation of evidence-based quantifiable risk of adverse events after rhinoplasty. Given this limitation, patients considering rhinoplasty are unable to fully ascertain preoperative risk, and the ability of physicians to obtain true informed consent is similarly flawed. This systematic review provides the first rigorous, comprehensive, and quantitative reporting of adverse events after rhinoplasty.
METHODS:This review was registered on the International Prospective Register of Systematic Reviews (PROSPERO) database (registration no. CRD42018081826) in April of 2018. Eligible articles were published in peer-reviewed journals with available abstracts and full-text articles. Interventions included primary functional, aesthetic, and combined functional/aesthetic rhinoplasty. The following data were extractedstudy size, population characteristics, indication, surgical approach, concomitant procedures, and incidence of adverse events.
RESULTS:A search yielded 3215 publications for title and abstract screening. Three hundred twenty-two were eligible for full-text review. Thirty-six met final inclusion criteria. A total of 13 adverse events were reported among these studies and included need for revision (0 to 10.9 percent), infection (0 to 4 percent), dehiscence (0 to 5 percent), bleeding (0 to 4.1 percent), septal perforation (0 to 2.6 percent), nasal airway obstruction requiring revision (0 to 3 percent), and hypertrophic scarring (0 to 1.5 percent).
CONCLUSIONS:This systematic review presents the first comprehensive and quantitative reporting of adverse event frequency after rhinoplasty. This is a crucial tool for preoperative patient counseling and an essential adjunct in the acquisition of informed consent. Future investigations will benefit from transparency and standardization of reporting to further quantify adverse event rates.
Although firms leverage social media platforms such as Facebook to engage with customers, they often treat social media elements and other online marketing activities such as search engine ...advertising as stand-alone, rather than part of an integrated online activities system. Hence, it is important to systematically understand how specific elements of social media, signifying and representing behavioural manifestations of brand engagement, relate to other online activities. We study how three types of brand engagement on social media - affiliation, conversation and responsiveness - influence search engine advertising effectiveness, including click-through rate and conversion rate. Specifically, we find that affiliation, conversation and responsiveness increase click-through rate and conversion rate. Moreover, brand engagement on social media strengthens the relationships between advertisement rank and search engine advertising effectiveness.
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BFBNIB, IZUM, KILJ, NUK, PILJ, SAZU, UL, UM, UPUK
Purpose Patients with locally advanced prostate cancer after radical prostatectomy are candidates for secondary therapy. However, this higher risk population is heterogeneous. Many cases do not ...metastasize even when conservatively managed. Given the limited specificity of pathological features to predict metastasis, newer risk prediction models are needed. We report a validation study of a genomic classifier that predicts metastasis after radical prostatectomy in a high risk population. Materials and Methods A case-cohort design was used to sample 1,010 patients after radical prostatectomy at high risk for recurrence who were treated from 2000 to 2006. Patients had preoperative prostate specific antigen greater than 20 ng/ml, Gleason 8 or greater, pT3b or a Mayo Clinic nomogram score of 10 or greater. Patients with metastasis at diagnosis or any prior treatment for prostate cancer were excluded from analysis. A 20% random sampling created a subcohort that included all patients with metastasis. We generated 22-marker genomic classifier scores for 219 patients with available genomic data. ROC and decision curves, competing risk and weighted regression models were used to assess genomic classifier performance. Results The genomic classifier AUC was 0.79 for predicting 5-year metastasis after radical prostatectomy. Decision curves showed that the genomic classifier net benefit exceeded that of clinical only models. The genomic classifier was the predominant predictor of metastasis on multivariable analysis. The cumulative incidence of metastasis 5 years after radical prostatectomy was 2.4%, 6.0% and 22.5% in patients with low (60%), intermediate (21%) and high (19%) genomic classifier scores, respectively (p <0.001). Conclusions Results indicate that genomic information from the primary tumor can identify patients with adverse pathological features who are most at risk for metastasis and potentially lethal prostate cancer.
This research draws on theoretical perspectives related to regulatory focus and self-view in the context of "green" advertising appeals. A pattern of results similar to that typically reported in the ...literature is replicated (i.e., promotion-framed messages are more persuasive for individuals with an active independent self-view, whereas prevention-framed messages are more persuasive for individuals with an active interdependent self-view)-but only when persuasive messages focus on personal health appeals. A considerably different set of relationships is observed when messages focus on environmental appeals. Consistent with our theoretical expectations regarding goal compatibility effects, prevention-(as opposed to promotion-) focused environmental appeals generated more favorable attitudes for individuals who are situationally primed to have an independent self-view. In the interdependent self-view condition, the promotion-focused appeals performed as well as or better than the prevention-focused appeals. The theoretical and managerial implications of these findings are discussed, and future research directions are offered.
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