title: The association between study characteristics and outcome in the relation between job stress and         cardiovascular disease - a multilevel meta-regression analysis.
abstract: OBJECTIVE
  Studies about job strain and cardiovascular disease (CVD) have yielded inconsistent results,         which hinders making a firm conclusion about the association. Inconsistent findings may be the result of methodological         differences. If the relative CVD risk is influenced by methodological differences, these differences should be explored         in more detail in future research to clarify which methodological characteristics are inherent to obtain the most         accurate estimate between job strain and CVD risk. By assessing how study characteristics are associated with the         outcome, we take the first step in unraveling this association. In this review, we explore the following research         question: are study characteristics associated with the size of the reported relative CVD risk?
  
  
  METHODS
  A systematic         literature search yielded 71 studies about job stress, assessed with the demand-control model, and CVD.         Traditional meta-regression was extended enabling the use of correlated data to quantify heterogeneity within and         between studies.
  
  
  RESULTS
  Compared to studies that use the original Job Content Questionnaire (JCQ), studies in which a         more deviant form of the JCQ was used yielded, on average, 43% higher estimates. Studies conducted in the USA yielded         about 26% lower estimates compared to studies conducted in Scandinavian countries.
  
  
  CONCLUSIONS
  Several study         characteristics are associated with the size of the reported relative CVD risk. Many of these study features are         related to the validity of the exposure and outcome assessment and are inherent to obtain an accurate estimate between         work stress and CVD risk. More research is needed to clarify why these study features impact the average relative CVD         risk.
authors.affiliation: Maastricht University, School CAPHRI, Department of Epidemiology, Maastricht, the Netherlands. karolina.szerencsi@maastrichtuniversity.nl
authors.forename: Karolina
authors.initials: K
authors.lastname: Szerencsi
authors.forename: Ludovic G P M
authors.initials: LG
authors.lastname: van Amelsvoort
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Viechtbauer
authors.forename: Danielle C L
authors.initials: DC
authors.lastname: Mohren
authors.forename: Martin H
authors.initials: MH
authors.lastname: Prins
authors.forename: Ijmert
authors.initials: I
authors.lastname: Kant
mesh_terms: D002055:Burnout, Professional; D002318:Cardiovascular Diseases / Q000150:complications / Q000523:psychology*; D006801:Humans; D012307:Risk Factors; D012537:Scandinavian and Nordic Countries; D013315:Stress, Psychological / Q000150:complications*; D011795:Surveys and Questionnaires