title: A randomized trial of the effect of vaccine injection speed on acute pain in infants.
abstract: This study compared the pain caused from fast vs. slow vaccine injections.
  
  
  
  Infants aged 2-6months receiving primary immunizations were randomized to fast (2-4mL/s) or slow (5-10mL/s) injections during routine 0.5mL Diphtheria, Tetanus, acellular Pertussis, Inactivated Polio Virus, Haemophilus influenzae type b vaccine (DTaP-IPV-Hib) injections. Those aged 2 and 4months additionally received 0.5mL Pneumococcal Conjugate Vaccine (PCV) injections. A research assistant and parent unaware of treatment allocation and hypothesis assessed pain using validated and recommended tools, including; the Modified Behavioural Pain Scale (MBPS, range 0-10), cry duration, and Numerical Rating Scale (NRS, range 0-10). The primary outcome was infant pain score using the MBPS.
  
  
  
  Altogether, 120 were recruited; 61 were randomized to fast injections and 59 to slow injections. One hundred and ninteen infants participated. There were no differences in characteristics, including; age (p=0.994) and sex (p=0.540). The mean MPBS score (standard deviation) during DTaP-IPV-Hib injection was lower in the fast injection group: 6.4 (2.7) vs. 7.4 (2.5), respectively; p=0.046. Regression analysis demonstrated a positive correlation between injection speed and pain. There were no other differences between groups.
  
  
  
  Fast injection reduced injection-induced pain in infants receiving DTaP-IPV-Hib but not PCV vaccine. Fast injections are recommended when administering vaccines because of the potential for a reduction in pain, feasibility and practicality.
  
  
  
  NCT02504398.
authors.affiliation: Leslie Dan Faculty of Pharmacy, University of Toronto, 144 College Street, Toronto, Ontario M5S 3M2, Canada; Child Health Evaluative Sciences, The Hospital for Sick Children, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada. Electronic address: anna.taddio@utoronto.ca.
authors.forename: Anna
authors.initials: A
authors.lastname: Taddio
authors.affiliation: Leslie Dan Faculty of Pharmacy, University of Toronto, 144 College Street, Toronto, Ontario M5S 3M2, Canada.
authors.forename: Horace
authors.initials: H
authors.lastname: Wong
authors.affiliation: Leslie Dan Faculty of Pharmacy, University of Toronto, 144 College Street, Toronto, Ontario M5S 3M2, Canada.
authors.forename: Ben
authors.initials: B
authors.lastname: Welkovics
authors.affiliation: Leslie Dan Faculty of Pharmacy, University of Toronto, 144 College Street, Toronto, Ontario M5S 3M2, Canada.
authors.forename: Angelo L
authors.initials: AL
authors.lastname: Ilersich
authors.affiliation: Paediatric Associates, 90 Warren Road, Suite 103, Toronto, Ontario M4V 2S2, Canada.
authors.forename: Mara
authors.initials: M
authors.lastname: Cole
authors.affiliation: Paediatric Associates, 90 Warren Road, Suite 103, Toronto, Ontario M4V 2S2, Canada.
authors.forename: Morton
authors.initials: M
authors.lastname: Goldbach
authors.affiliation: Paediatric Associates, 90 Warren Road, Suite 103, Toronto, Ontario M4V 2S2, Canada; Department of Paediatrics, The Hospital for Sick Children, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada.
authors.forename: Moshe
authors.initials: M
authors.lastname: Ipp
mesh_terms: D059787:Acute Pain / Q000209:etiology*; D015721:Diphtheria-Tetanus-Pertussis Vaccine / Q000009:adverse effects; D005260:Female; D018073:Haemophilus Vaccines / Q000009:adverse effects; D006801:Humans; D007223:Infant; D007273:Injections, Intramuscular / Q000009:adverse effects* / Q000379:methods*; D008297:Male; D010147:Pain Measurement; D000073818:Procedural Pain / Q000209:etiology; D022242:Pneumococcal Vaccines / Q000009:adverse effects; D011054:Poliovirus Vaccine, Inactivated / Q000009:adverse effects; D014611:Vaccination / Q000009:adverse effects* / Q000379:methods*; D018074:Vaccines, Conjugate / Q000009:adverse effects
chemical_list: D015721:Diphtheria-Tetanus-Pertussis Vaccine; D018073:Haemophilus Vaccines; D022242:Pneumococcal Vaccines; D011054:Poliovirus Vaccine, Inactivated; D018074:Vaccines, Conjugate; C541234:diphtheria-tetanus-five component acellular pertussis-inactivated poliomyelitis -Haemophilus influenzae type b conjugate vaccine
keywords: Infant; Injection technique; Pain management; Speed of injection; Vaccination