Whole-body vibration training improves balance control and sit-to-stand performance among middle-aged and older adults: a pilot randomized controlled trial

Background

Aging is associated with decreased balance, which increases falling risk. The objective of the current study was to determine the feasibility and effects of whole-body vibration (WBV) training on knee extensor muscle power, limits of stability, and sit-to-stand performance among community-dwelling middle-aged and older adults in the United States.

Methods

A randomized pilot study with participant blinding was conducted. Feasibility outcomes included recruitment and compliance rate. Twenty-nine community-dwelling older adults were randomly assigned to perform body-weight exercises with either an individualized vibration frequency and amplitude, a fixed vibration frequency and amplitude, or no vibration. Isokinetic knee extensor power, limits of stability, and sit-to-stand tests were conducted before beginning the exercises (baseline) and after 8 weeks of training.

Results

With a favorable recruitment rate (58%) and compliance rates (attrition 9%; adherence 85%), the intervention was deemed feasible. The limits of stability endpoint excursion score for the individualized frequency–amplitude group was increased by 8.8 (12.9%; P = 0.025) after training, and that group’s maximum excursion score was increased by 9.2 (11.5%; P = 0.006) after training. The average weight transfer time score was significantly decreased by 0.2 s in the fixed group. The participants in the individualized group demonstrated a significant increase (3.2%) in weight rising index score after 8 weeks of WBV training.

Conclusions

WBV training is feasible for use with elderly people, and this study achieved good recruitment and compliance. The present paper suggests that 8 weeks of WBV training improves limits of stability and sit-to-stand performance. Future studies must determine whether WBV training improves other factors that affect posture control.

Trial registration

This study was registered at the Texas Woman’s University Institutional Review Board [TWU IRB 17632] on the 3rd of November 2014.

     

The Contribution of Drug Overdose to Educational Gradients in Life Expectancy in the United States, 1992–2011

Since the mid-1990s, the United States has witnessed a dramatic rise in drug overdose mortality. Educational gradients in life expectancy widened over the same period, and drug overdose likely plays a role in this widening, particularly for non-Hispanic whites. The contemporary drug epidemic is distinctive in terms of its scope, the nature of the substances involved, and its geographic patterning, which influence how it impacts different education groups. I use vital statistics and National Health Interview Survey data to examine the contribution of drug overdose to educational gradients in life expectancy from 1992–2011. I find that over this period, years of life lost due to drug overdose increased for all education groups and for both males and females. The contribution of drug overdose to educational gradients in life expectancy has increased over time and is greater for non-Hispanic whites than for the population as a whole. Drug overdose accounts for a sizable proportion of the increases in educational gradients in life expectancy, particularly at the prime adult ages (ages 30–60), where it accounts for 25 % to 100 % of the widening in educational gradients between 1992 and 2011. Drug overdose mortality has increased more rapidly for females than for males, leading to a gender convergence. These findings shed light on the processes driving recent changes in educational gradients in life expectancy and suggest that effective measures to address the drug overdose epidemic should take into account its differential burden across education groups.     

The political economy of changes in family and old‐age welfare policy spending: Analysis of OECD countries, 1998–2011

This study investigated whether in times of budget constraints and in countries with relatively large family policy spending, family policy has an advantage in the budget competition with old‐age expenditures, compared with countries with a lower level of family policy spending. We employed pooled time‐series cross‐sectional analysis of 24 OECD countries from 1998 to 2011. Our findings suggest that the initial level of family spending tends to moderate the crowding‐out effect of old‐age spending, indicating that the more mature a family spending policy is, the more it resists budget competition from old‐age policy. Furthermore, the size of government debt was found to have an insignificant effect on welfare budgeting. Our findings indicate that retrenchment in welfare spending for old age cannot be fully explained by budget constraints. Politics among interest groups associated with different welfare programmes can be an important determinant in explaining changes in spending on each welfare programme.     

From statistical power to statistical assurance: It's time for a paradigm change in clinical trial design

A well-designed clinical trial requires an appropriate sample size with adequate statistical power to address trial objectives. The statistical power is traditionally defined as the probability of rejecting the null hypothesis with a pre-specified true clinical treatment effect. This power is a conditional probability conditioned on the true but actually unknown effect. In practice, however, this true effect is never a fixed value. Thus, we discuss a newly proposed alternative to this conventional statistical power: statistical assurance, defined as the unconditional probability of rejecting the null hypothesis. This kind of assurance can then be obtained as an expected power where the expectation is based on the prior probability distribution of the unknown treatment effect, which leads to the Bayesian paradigm. In this article, we outline the transition from conventional statistical power to the newly developed assurance and discuss the computations of assurance using Monte Carlo simulation-based approach.     

Enduring image: Capturing defining moments in crises

In today's media environment, crises are magnified as media events and are rich sites for the inception of images. Particular images, like a photograph or a sound bite are found to endure as representations of defining moments of crises. This study seeks to examine the concept of an enduring image, how it is engendered and how it impacts crisis communication efforts. The study utilizes five case studies of crisis with an inherent enduring image. An enduring image constitutes a prime representation of the accused in a given crisis. These images are loaded with symbolic potential and exhibit a sense of permanence in public consciousness. Understanding the implications of an enduring image can offer insights to organizations on how to better manage one's public and media image during or after a crisis. The study is arguably the first in examining the significance and potency of enduring images in crises.     

Does similarity breed marital and sexual satisfaction?

This study examined the effect of socioeconomic-cultural homogamy on the marital and sexual satisfaction of Hong Kong Chinese couples. Using a representative, territory-wide sample of 1,083 first-time married heterosexual couples, this study found that wives were generally less satisfied than their husbands with their marital and sexual relationships. Husbands were more likely to be satisfied with their marriages when they were two to four years older than their wives than when they were of similar age to their wives (i.e., within one year of each other), but they were less likely to be satisfied with their marriages when only their wives were employed than when both partners were employed. In addition, they were less likely to be satisfied with both their marital and sexual relationships when their wives were five or more years older. Wives with an older husband were more likely to be sexually satisfied than wives of the same age as their husband, but they were less likely to be satisfied with their marriages when they were better educated than their husbands. The implications of the findings are discussed.     

Designing and implementing an evaluation of a national work support program

Welfare reforms in the 1990s have shifted governments around the world towards financial assistance conditional on work. While large-scale rigorous research on welfare-to-work programs has demonstrated effectiveness towards employment in other countries, no such micro-level evaluation of a policy has ever been conducted in Singapore. This article describes the process of developing a large experimental evaluation of the Work Support Program, which the Ministry of Community Development, Youth and Sports started in 2006. The lessons learned from planning and implementing the research can be helpful to future researchers in negotiating long-term rigorous evaluations in an environment where collaborators lack sufficient research knowledge. Insights include ways to focus on the essentials, find alternative experimental designs, collaborate effectively, and adapt instruments across cultures.     

Longitudinal Change in Adolescent Depression and Anxiety Symptoms from before to during the COVID-19 Pandemic

This study aimed to examine changes in depression and anxiety symptoms from before to during the first 6 months of the COVID-19 pandemic in a sample of 1,339 adolescents (9–18 years old, 59% female) from three countries. We also examined if age, race/ethnicity, disease burden, or strictness of government restrictions moderated change in symptoms. Data from 12 longitudinal studies (10 U.S., 1 Netherlands, 1 Peru) were combined. Linear mixed effect models showed that depression, but not anxiety, symptoms increased significantly (median increase = 28%). The most negative mental health impacts were reported by multiracial adolescents and those under ‘lockdown’ restrictions. Policy makers need to consider these impacts by investing in ways to support adolescents’ mental health during the pandemic.     

Opportunism in Capital Budget Recommendations: The Effects of Past Performance and Its Attributions*

This study uses an experiment to examine the separate and combined effects of managers' loss aversion and their causal attributions about their divisions' performance on tendencies to make goal‐incongruent capital budget recommendations. We find that managers' recommendations are biased by their loss aversion. In particular, managers of high‐performing divisions are more likely than managers of low‐performing divisions to propose investments that maximize their division's short‐term profits at the expense of the firm's long‐term value. We also find that managers' recommendations are biased by their causal attributions. In particular, managers are more likely to propose investments that maximize their division's short‐term profits at the expense of the firm's long‐term value when they attribute their division's performance to external causes (e.g., task difficulty or luck) rather than to internal causes (e.g., managerial ability or effort). Further, the effects of causal attributions are greater for managers of high‐performing divisions than for managers of low‐performing divisions. The study's findings are important because loss aversion and causal attributions are often manifested in firms. Thus, they may bias managers' decisions, which in turn may be detrimental to the firms' long‐term value.     

Sex With Chinese Characteristics: Sexuality Research in/on 21st-Century China

This article examines the changing contours of Chinese sexuality studies by locating recent research in historical context. Our aim is to use the literature we review to construct a picture of the sexual landscape in China and the sociocultural and political conditions that have shaped it, enabling readers unfamiliar with China to understand its sexual culture and practices. In particular, we focus on the consequences of recent changes under the Xi regime for individuals’ sexual lives and for research into sexuality. While discussing the social and political regulation of sexuality, we also attend to the emergence of new forms of gendered and sexual subjectivity in postsocialist China. We argue throughout that sexuality in China is interwoven with the political system in a variety of ways, in particular through the tension between neoliberal and authoritarian styles of governance. We explore normative and dissident sexualities as well as forms of sexual conduct that are officially “deviant” but nonetheless tolerated or even tacitly enabled by the party-state. In particular, we highlight the dilemmas and contradictions faced by China’s citizens as they negotiate their sexual lives under “socialism with Chinese characteristics.”