Assessing the complexity of interventions within systematic reviews: development, content and use of a new tool (iCAT_SR).

Background: Health interventions fall along a spectrum from simple to more complex. There is wide interest in methods for reviewing 'complex interventions', but few transparent approaches for assessing intervention complexity in systematic reviews. Such assessments may assist review authors in, for example, systematically describing interventions and developing logic models.

Assessment of vibration of effects due to model specification can demonstrate the instability of observational associations.

Objectives: Model specification-what adjusting variables are analytically modeled-may influence results of observational associations. We present a standardized approach to quantify the variability of results obtained with choices of adjustments called the "vibration of effects" (VoE).

Study Design And Setting: We estimated the VoE for 417 clinical, environmental, and physiological variables in association with all-cause mortality using National Health and Nutrition Examination Survey data.

Testing the PRISMA-Equity 2012 reporting guideline: the perspectives of systematic review authors.

Reporting guidelines can be used to encourage standardised and comprehensive reporting of health research. In light of the global commitment to health equity, we have previously developed and published a reporting guideline for equity-focused systematic reviews (PRISMA-E 2012). The objectives of this study were to explore the utility of the equity extension items included in PRISMA-E 2012 from a systematic review author perspective, including facilitators and barriers to its use.

Assessing the applicability of findings in systematic reviews of complex interventions can enhance the utility of reviews for decision making.

Assessment of applicability is an essential part of the systematic review process. In the context of systematic reviews of the effects of interventions, applicability is an assessment of whether the findings of a review can be applied in a particular context or population. For more complex interventions, assessing applicability can be challenging because of greater diversity of, and interactions within and between, the intended population, intervention components, comparison conditions, and outcomes as well as a range of further considerations related to intervention context and theoretical basis.