Properties of the weighted log‐rank test in the design of confirmatory studies with delayed effects

Proportional hazards are a common assumption when designing confirmatory clinical trials in oncology. This assumption not only affects the analysis part but also the sample size calculation. The presence of delayed effects causes a change in the hazard ratio while the trial is ongoing since at the beginning we do not observe any difference between treatment arms, and after some unknown time point, the differences between treatment arms will start to appear. Hence, the proportional hazards assumption no longer holds, and both sample size calculation and analysis methods to be used should be reconsidered. The weighted log‐rank test allows a weighting for early, middle, and late differences through the Fleming and Harrington class of weights and is proven to be more efficient when the proportional hazards assumption does not hold. The Fleming and Harrington class of weights, along with the estimated delay, can be incorporated into the sample size calculation in order to maintain the desired power once the treatment arm differences start to appear. In this article, we explore the impact of delayed effects in group sequential and adaptive group sequential designs and make an empirical evaluation in terms of power and type‐I error rate of the of the weighted log‐rank test in a simulated scenario with fixed values of the Fleming and Harrington class of weights. We also give some practical recommendations regarding which methodology should be used in the presence of delayed effects depending on certain characteristics of the trial.     

Data envelopment analysis in the presence of measurement error: case study from the National Database of Nursing Quality Indicators® (NDNQI®)

Data envelopment analysis (DEA) is the most commonly used approach for evaluating healthcare efficiency [B. Hollingsworth, The measurement of efficiency and productivity of health care delivery. Health Economics 17(10) (2008), pp. 1107–1128], but a long-standing concern is that DEA assumes that data are measured without error. This is quite unlikely, and DEA and other efficiency analysis techniques may yield biased efficiency estimates if it is not realized [B.J. Gajewski, R. Lee, M. Bott, U. Piamjariyakul, and R.L. Taunton, On estimating the distribution of data envelopment analysis efficiency scores: an application to nursing homes’ care planning process. Journal of Applied Statistics 36(9) (2009), pp. 933–944; J. Ruggiero, Data envelopment analysis with stochastic data. Journal of the Operational Research Society 55 (2004), pp. 1008–1012]. We propose to address measurement error systematically using a Bayesian method (Bayesian DEA). We will apply Bayesian DEA to data from the National Database of Nursing Quality Indicators^® to estimate nursing units’ efficiency. Several external reliability studies inform the posterior distribution of the measurement error on the DEA variables. We will discuss the case of generalizing the approach to situations where an external reliability study is not feasible.     

Risky Business: Is There an Association between Casual Sex and Mental Health among Emerging Adults?

A multiethnic sample of single, heterosexual, emerging-adult college students (N = 3,907) ages 18 to 25, from 30 institutions across the United States, participated in a study about identity, culture, psychological well-being, and risky behaviors. Given ongoing debates about the connection between casual sex and psychological adjustment, in the current study we assessed the cross-sectional association of participation in casual sex with psychological well-being and distress. A greater proportion of men (18.6%) compared to women (7.4%) reported having had casual sex in the month prior to assessment. Structural equation modeling indicated that casual sex was negatively associated with well-being (ß = .20, p < .001) and positively associated with psychological distress (ß = .16, p < .001). Gender did not moderate these associations. For emerging-adult college students, engaging in casual sex may elevate risk for negative psychological outcomes.     

Structured Voluntary Youth Activities and Positive Outcomes in Adulthood: An Exploratory Study of Involvement in Scouting and Subjective Well-Being

This study explores whether youth involvement in Scouting has positive consequences later in life. We examine whether the number of years of participation in Scouting is positively associated with human and social capital and recreational lifestyles in adulthood, and whether these are linked to subjective well-being: relational, emotional, and physical health. To explore this potential relationship, we estimated a structural equation model, analyzing data from a national sample of adult males. We found that youth involvement in Scouting is positively related to subjective well-being indirectly via the positive adult outcomes.     

Evaluation of a Training to Reduce Provider Bias Toward Pregnant Patients With Substance Abuse

The objective of this article is not to present a scientific or systematic study, but to provide an initial framework for designing a training workshop to enhance health practitioners’ (nurses, social workers, physicians, etc.) knowledge regarding substance abuse treatment and to decrease their bias toward substance-abusing women, particularly pregnant women in rural communities. We incorporated the 4 Transdisciplinary Foundations from the Substance Abuse and Mental Health Services Administration Competencies Model, with specific competencies targeted that related to provider bias. After the conference, 52 of the 70 participants completed a questionnaire to self-assess knowledge level and confidence in skill related to substance abuse management. Participant mean scores were statistically significantly higher following the conference than 1 week prior (p < .001) in the area of “gender difference with substance abuse,” moving from an average of 2.6 to 4.5 on a 5-point Likert scale. Our conference was successful in increasing attendees’ knowledge about gender difference and substance abuse among pregnant patients.     

An Evaluation of Stimulus Preference Assessment Methodology in Organizational Behavior Management

The organizational behavior management literature has yielded few stimulus preference assessment methodologies for use with employees. The current investigation compared three preference assessments (ranking, survey, and multiple stimulus without replacement procedures) found in the organizational behavior management literature for their ability to predict reinforcers for direct care staff members’ behavior. In the first experiment all assessments were effective for predicting reinforcers, but the results were limited by a lack of control items in the assessment. In the second experiment the survey and ranking assessments both proved to be effective for identifying reinforcers and neutral or ineffective stimuli. Implications of these results and directions for future research are discussed.     

DEREGULATION AND THE RELIGIOUS MARKET IN TAIWAN: A Research Note

The religious economy model predicts that when encountered with competition, loosely organized religions will fail or will be transformed into congregational religions. Over time, competition will drive congregational religions to establish an extended relationship with their consumers by generating exclusivist claims and exclusivist socialization. And thus exclusive religion tends to occupy the biggest market share. This model, however, has rarely been tested empirically. By analyzing religious trends in Taiwan after the deregulation of the late 1980s, we find that state suppression contributed to the weakness of organized religion while enhancing the popularity of unchurched congregational religions in Taiwan. We also find that deregulation is associated with the rise of organized and congregational faiths. But whether or not these newly organized religions become exclusive or not needs further studies. Implications of the findings for future research are offered.     

Acculturation status and sexuality among female Cuban American college students

The authors examined relations among different measures of acculturation, and between acculturation and sexual behavior, in a sample of female Cuban American college students (n=61, M age = 18.4 years) who completed self-report surveys. In the first set of analyses, weak to moderate associations emerged among 4 measures of acculturation (birthplace, childhood language use, current language use, and ethnic identity), suggesting that inconsistent findings from prior research may have resulted from measurement limitations. In multivariate analyses, the authors examined predictors of sexual behavior and found that 1 aspect of acculturation (higher levels of ethnic identity) and background characteristics (being older and less religious) were associated with voluntary sexual intercourse. Moreover, higher levels on a sexual risk composite were associated with being born in the United States, more ethnically identified, older, and less religious. These analyses highlight the need for specificity in assessing acculturation in a college student population and support the need to examine cultural factors directly in sexuality research.