Study | Participants | Injection | Intervention | Comparison | Outcomes | Bias/limitations |
---|---|---|---|---|---|---|
Yilmaz et al. |
60 patients (surgery clinic) balanced for sex/age/BMI and randomized into 2 groups. | Diclofenac sodium 3 mL; Needle: 21 G, 38 mm length; Dorsogluteal site. Positioning: face up, internal rotation of femur both in intervention and in control group. | Technique used to improve safety: ZTT performed with a displacement of 1–2 cm and combined with air-lock technique (0.3 mL of air previously drawn into the syringe). It is not specified if the injection has been associated with standard speed of 0.1 mL/s or faster (21 G needle). |
Standard technique (stretching) | Statistically significant reduction in drug leakage ( |
One confounding variable: It is difficult to establish the differential contribution related to air-lock technique and ZTT, but the combination of the 2 techniques is also possible, and this publication has shown the effectiveness of ZTT along air-lock (0.3 mL). The sample is not very large for obtaining results’ generalization. |
Cook and Murtagh |
566 children aged 2–18 months in good health; infants with neurological diseases/ history of severe immediate allergic or anaphylactic reaction to any vaccine antigen were excluded. | Vaccine solution: anti haemophilus influenzae B. Needle: 25 G, 16 mm length, fully entered at 90° to the skin surface using the stretching technique in infants rather than grasping/bunching up method in infants; on the contrary CDC [45] recommend 25 G 25 mm needle in infants (1–12 months). VG site, vaccine in VG site allowing the infant to remain on the mother’s legs maintaining maternal contact (intervention) versus ALT site on the bed, observing vaccine administration in front of their eyes (control). | IMI (vaccine) in VG site (conversely CDC [6] recommend ALT site as preferred site in neonate/infants/toddlers). | Same injection and technique in ALT site | Safety improvement: Local reactions in the injection site were reduced with high statistical significance in the intervention group compared to the control one. |
No bias/limitations were detected. The outcomes demonstrate with high statistical significance the validity of the research hypothesis, despite the fact that the trial deviated from the CDC guidelines. |
Ipp et al. |
113 infants aged 4–6 months, balanced for age and possible intake of oral analgesics before vaccination. Sample unbalanced by gender. | 113 infants aged 4–6 months, balanced for age and possible intake of oral analgesics before vaccination. Sample unbalanced by gender. | 113 infants aged 4–6 months, balanced for age and possible intake of oral analgesics before vaccination. Sample unbalanced by gender. | 10 s aspiration performed before c + slow injection + slow withdrawal. | Safety outcome: no immediate adverse events were reported with either injection technique. Pain outcome: the immediate pain was greater in the standard versus pragmatic groups. The immunization pain score was measured within 15 s/30 s of the immunization, preceded by a baseline pain score 5 s prior to the vaccine injection. Measurements (high statistical significance): MBPS: Infant crying time assessed from videotape analysis (coder blinding): Percentage of crying infants Pain assessment from parents based on a VAS of 0–10: Pain assessment from physicians based on a VAS of 0–10: |
The high degree of confounding variables of the RCT is represented by having associated in a single intervention and relative observation, 3 variables in each randomized group: Experimental group: no 10 s aspiration previous IMIs + rapid injection + rapid withdrawal; Control group: 5–10 s aspiration performed |
Girish and Ravi |
200 healthy infants aged 1.5–18.0 months, with no significant differences in age, gender, and weight in the 2 randomized group of 100 infants; pre-vaccination analgesics were not used. | DTwP vaccine solution (0.5 mL) administered in ALT. |
No 10 s aspiration previous IMIs + rapid needle’s advancement into the muscle + rapid injection + rapid withdrawal: entire procedure completed in 1–2 s. | Slow advancement of the needle into the muscle + 5 s/10 s aspiration performed before IMIs + slow injection + slow withdrawal; entire procedure completed in 5 s/10 s. | Safety: no immediate adverse events were reported with either injection technique. |
Exclusive detection of immediate pain, without monitoring its progression in the 24 h following the injection (fever and irritability/ persistent infants crying or screaming in the delta T home time interval up to 24 h following injection); also the scores related to local reactogenicity in the delta T time interval up to 72 h following injection have not been measured. Berger and Williams aspiration of 5–10 s performed before IMIs has never been supported by scientific evidence in muscles suitable for immunization |
Abdelkhalek |
30 participants in the group I (shot blocker versus standard technique for IMIs) |
Drug solution: neurovit 3mL, dorsogluteal muscle, 23 G (length not reported). Positioning: lateral position with knee slightly flexed. | Group I: shot blocker during IMIs. |
Standard technique | The VDS, 6 pain descriptors) was compiled by the researcher who interviewed the patients in the immediate time after each injection: pain score was reduced both in groups I (shot blocker) and II (ZTT and WAST) compared to standard technique: |
There is no mention of blinding with respect to the technique adopted for both the patients and the researcher administering the IMIs, as well as for the researcher administering the questionnaires. |
Kara and Yapucu Gunes |
86 randomized patient in postoperative care, with mean age of 46.4 ± 15.1 years;, and 38.7% of women and 46% of men; not homogeneous for BMI (mean BMI was 27.1 ± 6.08). | Diclofenac sodium (3 mL), needle: 21 G, inserted at 90°; length associated with BMI not reported. |
Technique improving safety: internal rotation of foot (B) 3 interventions in the same patient (crossover study) chosen in a random sequence with intervals of 8 h used to estimate pain: Positioning: prone with toes pointing down during injection with standard technique (not declared); Positioning: prone with internal rotation of 1 foot (relaxation) during injection with standard technique (not declared); Same positioning in A combined with ZTT with displacement of 2.5 cm along air-lock (0.2 mL of air), and with slow technique both in injection and in needle’s withdrawal. |
(A) versus (B) versus (C) | VAS was used to assess the level of pain associated with varying BMI and with each intervention: |
In addition to injection pain, participants were already experiencing postoperative pain; moreover, both aspiration |
Shankar et al. |
400 arms of 200 adult Indians balanced for gender, without scars and/or certain systemic diseases with varying age and BMIs (mean BMI of 24.2); radiology department. | Deltoid side, both left and right sides (in the sample all participants stated that the right arm corresponded to the dominant one). |
Safety improvement: to make subsequent protocols for IMIs on the deltoid side safer. SM, MB, and SB |
Comparison between gender and side differences in the SM and MB thickness at the deltoid site for IMIs. | Assuming a standard needle length of 25 mm, the prevalence of overpenetration in Indian adults was 50% (both male and female), while underpenetration was 1%. |
Missing data: It was not reported which solution was injected, but it is supposed there was performed only needle’s insertion in the deltoid site. Cook’s |