Bmc Med Res Methodol
-
Bmc Med Res Methodol · Mar 2012
Hospital-level associations with 30-day patient mortality after cardiac surgery: a tutorial on the application and interpretation of marginal and multilevel logistic regression.
Marginal and multilevel logistic regression methods can estimate associations between hospital-level factors and patient-level 30-day mortality outcomes after cardiac surgery. However, it is not widely understood how the interpretation of hospital-level effects differs between these methods. ⋯ Marginal and multilevel models take different approaches to account for correlation between patients within hospitals and they lead to different interpretations for hospital-level odds ratios.
-
Bmc Med Res Methodol · Feb 2012
A simple method for estimating relative risk using logistic regression.
Odds ratios (OR) significantly overestimate associations between risk factors and common outcomes. The estimation of relative risks (RR) or prevalence ratios (PR) has represented a statistical challenge in multivariate analysis and, furthermore, some researchers do not have access to the available methods. ⋯ This simple tool could be useful for calculating the effect of risk factors and the impact of health interventions in developing countries when other statistical strategies are not available.
-
Bmc Med Res Methodol · Jan 2012
Patient, caregiver, health professional and researcher views and experiences of participating in research at the end of life: a critical interpretive synthesis of the literature.
The development of the evidence-base informing end of life (EoL) care is hampered by the assumption that patients at the EoL are too vulnerable to participate in research. This study aims to systematically and critically review the evidence regarding the experiences and views of patients, caregivers, professionals and researchers about participation in EoL care research, and to identify best practices in research participation. ⋯ The evidence explored within this study demonstrates that the ethical concerns regarding patient participation in EoL care research are often unjustified. However, research studies in EoL care require careful design and execution that incorporates sensitivity to participants' needs and concerns to enable their participation. An innovative conceptual model for research participation relevant for potentially vulnerable people was developed.
-
Bmc Med Res Methodol · Jan 2012
Quality assessment of systematic reviews or meta-analyses of nursing interventions conducted by Korean reviewers.
A systematic review is used to investigate the best available evidence of clinical safety and effectiveness of healthcare intervention. This requires methodological rigor in order to minimize bias and random error. The purpose of this study is to assess the quality of systematic reviews or meta-analyses for nursing interventions conducted by Korean researchers. ⋯ The methodological quality of published reviews on nursing interventions conducted by Korean reviewers was assessed as low to moderate. In order to use the best available evidence in clinical decision making, reviewers should conduct systematic reviews or meta- analyses using rigorous research methods.
-
Bmc Med Res Methodol · Jan 2012
ReviewA review of the reporting and handling of missing data in cohort studies with repeated assessment of exposure measures.
Retaining participants in cohort studies with multiple follow-up waves is difficult. Commonly, researchers are faced with the problem of missing data, which may introduce biased results as well as a loss of statistical power and precision. The STROBE guidelines von Elm et al. (Lancet, 370:1453-1457, 2007); Vandenbroucke et al. (PLoS Med, 4:e297, 2007) and the guidelines proposed by Sterne et al. (BMJ, 338:b2393, 2009) recommend that cohort studies report on the amount of missing data, the reasons for non-participation and non-response, and the method used to handle missing data in the analyses. We have conducted a review of publications from cohort studies in order to document the reporting of missing data for exposure measures and to describe the statistical methods used to account for the missing data. ⋯ This review highlights the inconsistent reporting of missing data in cohort studies and the continuing use of inappropriate methods to handle missing data in the analysis. Epidemiological journals should invoke the STROBE guidelines as a framework for authors so that the amount of missing data and how this was accounted for in the analysis is transparent in the reporting of cohort studies.