Procedural and Physical Interventions for Vaccine Injections Systematic Review of Randomized Controlled Trials and Quasi-Randomized Controlled Trials

Design/Methods: Databases were searched using a broad search strategy to identify relevant randomized and quasi-randomized controlled trials. Data were extracted according to procedure phase (preprocedure, acute, recovery, and combinations of these) and pooled using established methods. Results: A total of 31 studies were included. Acute infant distress was diminished during intramuscular injection without aspiration (n=313): standardized mean difference (SMD) 0.82 (95% confidence interval [CI]: 1.18, 0.46). Injecting the most painful vaccine last during vaccinations reduced acute infant distress (n=196): SMD 0.69 (95% CI: 0.98, 0.4). Simultaneous injections reduced acute infant distress compared with sequential injections (n=172): SMD 0.56 (95%CI: 0.87, 0.25). There was no benefit of simultaneous injections in children. Less infant distress during the acute and recovery phases combined occurred with vastus lateralis (vs. deltoid) injections (n=185): SMD 0.70 (95%CI: 1.00, 0.41). Skin-to-skin contact in neonates (n=736) reduced acute distress: SMD 0.65 (95% CI: 1.05, 0.25). Holding infants reduced acute distress after removal of the data from 1 methodologically diverse study (n=107): SMD 1.25 (95% CI: 2.05, 0.46). Holding after vaccination (n=417) reduced infant distress during the acute and recovery phases combined: SMD 0.65 (95% CI: 1.08, 0.22). Self-reported fear was reduced for children positioned upright (n=107): SMD 0.39 (95% CI: 0.77, 0.01). Non-nutritive sucking (n=186) reduced acute distress in infants: SMD 1.88 (95% CI: 2.57, 1.18). Manual tactile stimulation did not reduce pain across the lifespan. An external vibrating device and cold reduced pain in children (n=145): SMD 1.23 (95% CI: 1.58, 0.87). There was no benefit of warming the vaccine in adults. Muscle tension was beneficial in selected indices of fainting in adolescents and adults.