Study quality is emerging as an essential component of evidence syntheses. It allows
practitioners and policymakers to make informed decisions based on the quality of the …

Background: No existing instrument addresses the minimum number of items that guarantee
methodological quality in studies based on observational methodology. Consequently …

The evaluation of the methodological quality of primary studies in systematic reviews is of
great importance in order to guarantee the validity and reliability of their results, but there is …

Background Assessment of the quality of included studies is an essential component of any
systematic review. A formal quality assessment is facilitated by using a structured tool. There …

The concept of validity has been a central component in critical appraisal exercises
evaluating the methodological quality of quantitative studies. Reactions by qualitative …

Assessing the quality of randomized controlled trials is a relatively new and important
development. Three approaches have been developed: component, checklist, and scale …

The number of qualitative research methods has grown substantially over the last thirty
years, both in social sciences and, more recently, in health sciences. This growth came with …

Survey research is the most frequently used data collection method in many disciplines.
Nearly, everybody agrees that such data contain serious measurement errors. However …

Praise for the First Edition"... this book is quite inspiring, giving many practical ideas for
survey research, especially for designing better questionnaires."—International Statistical …

Assessments of studies meant to evaluate the effectiveness of interventions, programs, and
policies can serve an important role in the interpretation of research results. However …