A comprehensive review of the healthy worker effect in occupational epidemiological studies

The reduction of mortality and morbidity rates among occupational cohort studies may be attributed to the presence of the healthy worker effect (HWE). Occupational epidemiologic studies investigating worker’s health are prone to the risk of having the HWE phenomenon and this special form of bias has been debated over the years. Hence, it’s imperative to explore in-depth the magnitude and sources of HWE, and further, elucidate the factors that may affect HWE and strategies reducing HWE. The HWE should be considered as a mixed bias between selection and confounding bias. The validity threats due to the HWE among morbidity studies are the same as the mortality studies. The consequent reduction due to the HWE in the association between the exposure and outcome may lead to underestimating some harmful exposures in the workplace or occupational settings. Healthy hire effect and healthy worker survivor effect are the main sources of HWE. Several factors can increase or decrease the probability of HWE; therefore, the investigators should consider them among future occupational epidemiological studies. Many strategies can help in reducing the impact of HWE, but each strategy has its weaknesses and strengths. Not all strategies can be applied among all occupational epidemiological studies. Mathematical procedures still need further investigations to be validated. HWE is a consequence of inappropriate comparison groups in nature. The usage of the general population as a reference group is not an appropriate choice. By considering the HWE sources and factors and using appropriate strategies, the impact of HWE may be reduced.

Gender Differences In Scores Of Anxiety And Depression Among Physical Therapy Students Of Saudi Arabia: A Cross-Sectional Study

Purpose: The current study aimed to determine the prevalence of depression and anxiety disorders among physical therapy students and to identify any gender differences. Methods: This study used a cross-sectional approach to investigate physical therapy students and collected data via the Beck Depression Inventory and Beck Anxiety Inventory as well as demographic and social information. Data collection occurred during the middle of the 2016/17 academic year, beginning in the second week of the academic term, and finishing in the fifth week. Data analysis was performed using descriptive statistics and chi-square tests. Results: Among the 215 students included in this study, the prevalence of anxiety and depression was 33% and 34% respectively. In addition, gender differences showed that female students were more likely to experience severe and moderate anxiety levels compared to male students. Conclusions: Physical therapy students reported alarming levels of anxiety and depression. Gender differences also existed with regard to anxiety and other factors. The presence of mental health concerns potentially compromises the academic achievement and quality of life for students. Urgent intervention is required to avoid or at least reduce such high levels of anxiety and depression among university students.