In longitudinal studies variables are measured repeatedly over time, leading to clustered
and correlated observations. If the goal of the study is to develop prediction models …

The topic of centering in multilevel modeling (MLM) has received substantial attention from
methodologists, as different centering choices for lower-level predictors present important …

Background Patients who have received mechanical ventilation can have prolonged
cognitive impairment for which there is no known treatment. We aimed to establish whether …

Introduction Several studies have documented increases in adolescent loneliness and
depression in the US, UK, and Canada after 2012, but it is unknown whether these trends …

The coronavirus disease 2019 pandemic upended work, family, and social life. These
massive changes may have created shifts in exposure to work-life conflict. Using a national …

Importance Suicide is a leading cause of death among 10-to 24-year-old individuals in the
United States; evidence on effective treatment for adolescents who engage in suicidal and …

Researchers often mention the utility and need for R-squared measures of explained
variance for multilevel models (MLMs). Although this topic has been addressed by …

Background The comparative effectiveness of performing instrumented (rigid pedicle screws
affixed to titanium alloy rods) lumbar spinal fusion in addition to decompressive laminectomy …

Purpose Today, organizations work hard to improve the motivation of their employees and
related knowledge, skills and abilities to enhance work performance. Among many other …

Importance Effective and efficient treatment is needed for posttraumatic stress disorder
(PTSD) in active duty military personnel. Objective To examine the effects of massed …