Related Experiment Video
Updated: Jul 13, 2026
Cheek Injection Model for Simultaneous Measurement of Pain and Itch-related Behaviors
Published on: September 27, 2019
Vaccine-related pain: randomised controlled trial of two injection techniques
Moshe Ipp1, Anna Taddio, Jonathan Sam
1Division of Pediatric Medicine and Pediatric Outcomes Research Team (PORT), Department of Pediatrics, Faculty of Medicine, University of Toronto, Canada. mm.ipp@utoronto.ca
Insights
A rapid injection technique significantly reduces infant pain during immunisation compared to the standard slow method. This pragmatic approach is recommended for routine vaccinations to minimize distress.
Area of Science:
- Pediatrics
- Pain Management
- Immunology
Background:
- Infant immunisation is essential for public health.
- Pain experienced during vaccination can cause distress and impact future vaccine uptake.
Purpose of the Study:
- To compare acute pain responses in infants receiving immunisations via a slow standard technique versus a rapid pragmatic technique.
Main Methods:
- A randomized controlled trial was conducted in a paediatric primary care setting.
- Healthy infants aged 4-6 months received DPTaP-Hib immunisation.
- Pain was assessed using the Modified Behavior Pain Scale (MBPS), crying duration, and visual analogue scales (VAS).
Main Results:
- Infants in the rapid injection group (pragmatic) experienced significantly less pain (lower MBPS scores) than those in the slow injection group (standard of care).
- The rapid technique group showed less crying (43% vs 82%), shorter crying duration, and quicker injection times.
- Parent and paediatrician VAS scores for pain were lower in the rapid injection group.
Conclusions:
- A rapid, pragmatic injection technique is less painful for infants during routine immunisation compared to the standard slow method.
- The findings support the recommendation of rapid injection techniques for intramuscular immunisations to reduce infant pain and distress.
Objective:
To compare acute pain response during immunisation in infants using a slow standard of care injection technique versus a rapid pragmatic technique.
Design:
Randomised controlled trial.
Setting:
Single-centre, urban paediatric primary care practice.
Subjects:
Healthy infants 4-6 months of age receiving their routine DPTaP-Hib immunisation.
Interventions:
Standard of care group: slow aspiration prior to injection, slow injection and slow withdrawal. Pragmatic group: no aspiration, rapid injection and rapid withdrawal.
Main Outcome Measures:
Immediate infant pain measured by the Modified Behavior Pain Scale (MBPS), crying and parent/paediatrician visual analogue scale (VAS).
Results:
113 infants participated; there were no observed differences in age, birth order or prior analgesic use. Mean MBPS scores (95% confidence interval (CI)) were higher (p<0.001) for the standard group compared to the pragmatic group, 5.6 (5 to 6.3) vs 3.3 (2.6 to 3.9). The standard group was more likely to cry, 47/57 (82%) vs 24/56 (43%), to cry longer, median (interquartile range (IQR)) 14.7 s (8.7-35.6) vs 0 s (0-11.30), and to take longer to have the vaccine injected, median (IQR) 8.8 s (7.9-10.3) vs 0.9 s (0.8-1.1), p<0.001 for all comparisons. The median (IQR) VAS scores by parents and paediatricians were higher for the standard group: VAS parent, 3.5 (1.6-5.5) vs 1.9 (0.1-3.1) and VAS paediatrician, 2.8 (2.0-5.1) vs 1.4 (0.2-2.4). There were no adverse events.
Conclusion:
Immunisation using a pragmatic rapid injection technique is less painful than a slow standard of care technique and should be recommended for routine intramuscular immunisations.
