Background: Systematic reviews often have narrowly focused review questions such as reviewing the efficacy of a very specific intervention. Such a narrow focus can make it easier to achieve homogeneity of research studies in the review but may limit the applicability of the review findings. A narrow focus may prevent the consideration of very similar interventions and may create empty or nearly empty reviews whereas a differently constructed review question may have included more studies and provided meaningful results for application to policy and practice. Similarly, rapid evidence assessment reviews are frequently proposed as a means to provide prompt responses to policy questions yet these can be very narrowly focused reviews with limited applicability. Objectives: The purpose of this symposium is to examine a range of methods for considering broad questions and heterogeneous data whilst maintaining the necessary rigour of systematic reviews. Methods: Examination of the advantages and disadvantages of approaches to enable breadth in reviews in relation to: (1) reviews of effectiveness; (2) reviews of other research questions. Results: The presentation will consider these issues in relation to Cochrane and Campbell methods and (i) mapping; (ii) reviews of reviews; (iii) quality and relevance appraisal; (iv) mixed methods and mixed knowledge reviews. Conclusions: The importance of selecting appropriate methods for enabling breadth and depth of question and working with heterogeneity of data when undertaking individual reviews and programmes of reviews.