Eligibility criteria
Studies were eligible for the review if they included:
Previous reviews have identified limited trials about interventions to prevent and manage anaphylaxis22Armstrong N, Wolff R, van Mastrigt G, Martinez N, Hernandez AV, Misso K, Kleijnen J. A systematic review and cost-effectiveness analysis of specialist services and adrenaline auto- injectors in anaphylaxis. Health Technol Assess 2013;17(17):1-117, v-vi.,33El Turki A, Smith H, Llewellyn C, Jones CJ. A systematic review of patients’, parents’ and healthcare professionals’ adrenaline auto-injector administration techniques. Emerg Med J 2017;34(6):403-416.,44Tejedor-Alonso MA, Farias-Aquino E, Pérez-Fernández E, Grifol-Clar E, Moro-Moro M, Rosado-Ingelmo A. Relationship between anaphylaxis and use of beta-blockers and angiotensin-converting enzyme inhibitors: a systematic review and meta-analysis of observational studies. J Allergy Clin Immunol Pract 2019;7(3):879-897.e5. so we included other comparative designs. Consecutive case series were eligible when studying diagnostic tests and adrenaline because expert advice suggested that it is difficult and potentially unethical to implement more robust designs in these areas. Registry studies, cohort studies and uncontrolled before-and-after studies were excluded in order to focus on the most robust comparative evidence.