A Cox-type regression model with change-points in the covariates

We consider a Cox-type regression model with change-points in the covariates. A change-point specifies the unknown threshold at which the influence of a covariate shifts smoothly, i.e., the regression parameter may change over the range of a covariate and the underlying regression function is continuous but not differentiable. The model can be used to describe change-points in different covariates but also to model more than one change-point in a single covariate. Estimates of the change-points and of the regression parameters are derived and their properties are investigated. It is shown that not only the estimates of the regression parameters are [Formula: see text] -consistent but also the estimates of the change-points in contrast to the conjecture of other authors. Asymptotic normality is shown by using results developed for M-estimators. At the end of this paper we apply our model to an actuarial dataset, the PBC dataset of Fleming and Harrington (Counting processes and survival analysis, 1991) and to a dataset of electric motors.     

Feasibility and Acceptability of Smartphone Assessment in Older Adults with Cognitive and Emotional Difficulties

This feasibility study assessed perceived acceptability, adherence rates, and reasons for nonadherence to smartphone-based ecological momentary assessment (EMA). At two sites, participants (n = 103) ages 65 years or older with diagnosed anxiety or depressive disorder and cognitive concerns responded three times daily to smartphone-based EMA questions assessing clinical outcomes for two 10-day periods. Quantitative and qualitative measures followed both 10-day EMA periods. Overall, 76% of participants completed surveys on ≥ 10 of the 20 assessment days, and 70% of participants completed at least 30% of the total surveys. Reasons for nonadherence included technical, logistical, physiological, and cognitive issues. Smartphone-based EMA is feasible in older adults with cognitive and emotional difficulties. EMA tools should be responsive to the needs and preferences of participants to ensure adequate acceptability and adherence in this population. Our findings can inform the design, development, and implementation of mobile technologies in older adults in research and clinical contexts.     

Stuck in a job: being “locked-in” or at risk of becoming locked-in at the workplace and well-being over time

In this study, being “locked-in” at the workplace is conceptualized as being in a non-preferred workplace while at the same time perceiving low employability. The aim of the study was to investigate how being locked-in or at risk of becoming locked-in (being in a non-preferred workplace yet currently satisfied, combined with perceiving low employability) relates to well-being (subjective health and depressive symptoms). The hypotheses were tested in a Swedish longitudinal sample (T1 in 2010 and T2 in 2012) of permanent employees (N?=?3491). The results showed that stability with regard to locked-in-related status (being non-locked-in, at risk of becoming locked-in, or locked-in at both T1 and T2) was related to significant and stable differences in well-being. The non-locked-in status was associated with better well-being than being at risk of becoming locked-in. Moreover, those at risk of becoming locked-in showed better well-being than those with stable locked-in status. Changes towards non-locked-in were accompanied by significant improvements in well-being, and changes towards locked-in were associated with impairments in well-being. The relationships that were found could not be attributed to differences in demographic variables and occupational preference. The findings indicate that being locked-in is detrimental to well-being. This has implications for preventative interventions.     

Trajectories of effort-reward imbalance in Swedish workers: Differences in demographic and work-related factors and associations with health

ABSTRACT

The aim of the study was to identify trajectories of effort-reward imbalance (ERI), to examine these with respect to demographic (age, gender, socio-economic position) and work-related (employment contract, work hours, shift work, sector) factors, and to investigate associations with different health indicators (self-rated health, depressive symptoms, migraine, sickness absence). The study used four waves of data (N?=?6702), collected biennially within the Swedish Longitudinal Occupational Survey of Health (SLOSH). Using latent class growth modelling, we identified four trajectories: a stable low imbalance trajectory, which comprised 90% of all participants, and three change trajectories including a decreasing trajectory (4% of the participants), an inverted U-shaped trajectory and an increasing imbalance trajectory, both in 3% of the participants. Results indicate that a sizeable proportion of Swedish employees’ experience imbalance between efforts and rewards at work. The most favourable trajectory comprised relatively more men and was characterised by better work-related characteristics than the less favourable ERI trajectories. All change trajectories were dominated by women and employees in the public sector. Health developments followed ERI trajectories, such that less favourable trajectories associated with impaired health and more favourable trajectories associated with better health. Sickness absence increased among all ERI trajectories, most so for the decreasing and increasing ERI trajectory.