The selection of search sources influences the findings of a systematic review of people’s views: a case study in public health

The contribution of 25 search sources in locating 28 studies included within a systematic review on UK children’s views of body size, shape and weight was analysed retrospectively. The impact of utilising seven search sources chosen to identify UK-based literature on the review’s findings was assessed.Over a sixth (5 out of 28) of the studies were located only through supplementary searches of three sources. These five studies were of a disproportionally high quality compared with the other studies in the review. The retrieval of these studies added direction, detail and strength to the overall findings of the review. All studies in the review were located within 21 search sources. Precision for 21 sources ranged from 0.21% to 1.64%.For reducing geographical bias and increasing the coverage and context-specificity of systematic reviews of people’s perspectives and experiences, searching that is sensitive and aimed at reducing geographical bias in database sources is recommended.Systematic reviews of people’s views, understandings, beliefs and experiences (‘views studies’) are valuable to policy-makers in providing contextual information on interventions to inform their development, implementation and evaluation [1]. We describe ‘views studies’ as those that are centred on people’s own voices; these are often qualitative, but not always [1]. Undertaking a systematic literature search for these studies contributes to the rigour and quality of the review findings, but the process of identifying research on people’s views can be challenging. Studies on people’s views tend to be dispersed across a range of subject disciplines, are diverse in their terminology, and exist in various publication formats. People’s views of public health issues potentially cross over the fields of social science, the environment, health and medicine, education and psychology. They are contained across a range of literature search sources from large ubiquitous databases to smaller specialised