A Cochrane review included 39 studies with a total of 3 394 subjects. The most commonly studied needle-procedures were venipuncture, intravenous (IV) line insertion, and immunizations. Studies included children aged 2 to 19 years, with the most evidence available for children under 12 years of age. Most commonly studied psychological interventions for needle procedures were distraction, hypnosis, and cognitive behavioural therapy (CBT). The majority of included studies (19 of 39) examined distraction: listening to music, watching cartoons, playing with a toy, non-procedural talk, squeezing a rubber ball, using cards with questions on them, listening via earphones to stories being sung or read, mother distraction including speaking, caressing, and soothing, or a combination or selection of various distractors such as toys, books, cartoons, games, or music.
Distraction reduced self-reported pain (SMD of -0.61, 95% CI -0.91 to -0.32, statistical heterogeneity I2=88%; 19 studies, n=1 759), and hypnosis reduced both self-reported pain (SMD -1.40, 95% CI -2.32 to -0.48, statistical heterogeneity I2=85%; 5 studies, n=176) and distress (SMD -2.53, 95% CI -3.93 to -1.12; 5 studies, n=176). Preparation and information, combined CBT, parent coaching plus distraction, suggestion, or virtual reality did not reduce children's pain and distress (2 to 4 studies for each type of intervention).
Comment: The quality of evidence is downgraded by study limitations (unclear allocation concealment and lack of blinding) and by inconsistency (statistical heterogeneity).