The application of research synthesis methods for evaluating primary research on Salmonella in broiler chickens
Research synthesis methods were applied to identify, appraise and summarize the primary research on 'Salmonella' in broiler chickens from farm-to-secondary processing pertaining to three sub-topics: interventions, risk factors, and prevalence. A scoping review was utilized to develop evidence maps for these sub-topics and prioritize 'a priori' determined questions for rigorous systematic reviews. Of 12, 982 potentially relevant citations, 748 studies addressed interventions, risk factors (n=30) or prevalence (n=200). Evidence maps of sub-topics indicated substantial heterogeneity in study methods. Among studies evaluating an on-farm intervention, competitive exclusion (CE, n=192) was the most frequently studied. The results of a systematic review-meta-analysis (SR-MA) indicated that various CE products reduced 'Salmonella' colonization in broilers, for up to13 weeks post-treatment. The methodological soundness of these studies was limited. The scoping review-SR-MA approach is useful for characterizing broad topics and prioritizing questions for SR, and should be considered for routine use in microbial food safety.