The Health and Retirement Study was designed to evaluate changes in health and labor force participation during and after the transition from working to retirement. Every 2 years, participants provided information about their self-rated health (SRH), body mass index (BMI), smoking status, and other characteristics. Our goal was to assess the effects of smoking and gender on trajectories of change in BMI and SRH over time. Joint longitudinal analysis of outcome measures is preferable to separate analyses because it allows to account for the correlation between the measures, to test the effects of predictors while controlling type I error, and potentially to improve efficiency. However, because SRH is an ordinal measure while BMI is continuous, formulating a joint model and parameter estimation is challenging. A joint correlated probit model allowed us to seamlessly account for the correlations between the measures over time. Established estimating procedures for such models are based on quasi-likelihood or numerical approximations that may be biased or fail to converge. Therefore, we proposed a novel expectation-maximization algorithm for parameter estimation and a Monte Carlo bootstrap approach for standard errors approximation. Expectation-maximization algorithms have been previously considered for combinations of binary and/or continuous repeated measures; however, modifications were needed to handle combinations of ordinal and continuous responses. A simulation study demonstrated that the algorithm converged and provided approximately unbiased estimates with sufficiently large sample sizes. In the Health and Retirement Study, male gender and smoking were independently associated with steeper deterioration in self-rated health and with lower average BMI. Copyright © 2016 John Wiley & Sons, Ltd.

%B Statistics in Medicine %V 35 %P 4202-4205 %8 10/2016 %G eng %U http://www.ncbi.nlm.nih.gov/pubmed/27222058 %N 23 %R 10.1002/sim.6982 %0 Journal Article %J Journal of Population Ageing %D 2011 %T Trends in Labor Force Participation: How Much is Due to Changes in Pensions? %A Michael D. Hurd %A Susann Rohwedder %K Labor force participation %K Older Adults %K Pensions %K Retirement Planning and Satisfaction %XIn the United States, beginning in the late 1980s there was a substantial increase in the labor force participation of men and women in their 60s. Over the same time period the type of pension plans offered by employers shifted strongly from defined benefit plans to defined contribution plans. Defined benefit plans typically have optimal retirement ages embedded in their structure which induce early retirement, whereas defined contribution plans do not favor any particular retirement age. Based on panel data, this paper quantifies the increase in participation due to the change in pension structure. The main result is that the pension changes account for a considerable part of the increase, but other factors also made a contribution.

%B Journal of Population Ageing %V 4 %P 81-96 %8 2011 Jun 1 %G eng %N 1-2 %R 10.1007/s12062-011-9042-8 %0 Report %D 2003 %T The Impact of Poor Health Behaviors on Workforce Disability %A Richardson, Caroline R. %A Jennifer T. Hanlon %A Hillary J. Mull %A Sandeep Vijan %A Rodney A. Hayward %A Linda A. Wray %A Kenneth Langa %K Disabilities %K Health Behavior %K Labor force participation %K Older Adults %X The effects of poor health habits on mortality have been studied extensively. However, few studies have examined the impact of these health behaviors on workforce disability. In the Health and Retirement Study, a nationally representative cohort of 6044 Americans who were between the ages of 51 and 61 and who were working in 1992, we found that both baseline smoking status and a sedentary lifestyle predict workforce disability six years later. If this relationship is causal, cost-benefit analyses of health behavior intervention that neglect workforce disability may substantially underestimate the benefits of such interventions. %I University of Michigan Retirement Research Center %C Ann Arbor %P 1-22 %8 06/2003 %G eng %U https://core.ac.uk/download/pdf/7189096.pdf