The Z-Track Technique as a Pain Management Strategy for Neonates During Intramuscular Injections: Insights from a Randomized Controlled Trial

Haidar J. Kareem1*, Zaid Waheed Ajil2

1AL- Muthanna Health Directorate, Ministry of Health, 879P+4XC, Samawah, Al Muthanna Governorate, Iraq

2Paediatric Nursing Department, College of Nursing, University of Baghdad, Baghdad Governorate, 992M+CV4, Baghdad, Iraq

*Corresponding Author’s Email: haidar.jumaa2304m@conursing.uobaghdad.edu.iq

ABSTRACT

Background: Intramuscular injections such as vitamin K supplements are very common within the first days of neonatal life and are deemed painful; therefore, nurses play a vital role during intramuscular injections by employing various non-pharmacological strategies to mitigate pain while taking into consideration ethical principles. Objectives: To assess the effects of using the Z-track technique (ZTT) as a pain management strategy for neonates during intramuscular injections. Methods: A Randomised Controlled Trial (RCT) that adopted a single-blind prospective design was performed on 80 term neonates who underwent vitamin K intramuscular injection during their first few hours of life. The sample were randomised into two groups: 40 neonates in the ZTT (interventional group) and 40 neonates in the control group. The experimental group received ZTT during intramuscular injection, and the control group received the standard method of injection. The main outcome assessment was the Neonatal/Infant Pain Scale (NIPS). Results: The NIPS mean scores were compared statistically, and a significant statistical difference was detected between the study and control groups (p value = 0.000), resulting in a lower pain score in the experimental group (3.28±1.08) than the control group (4.53±1.26) with a mean difference of -1.25. Conclusions: The study concluded the utilising of the ZTT is considered an effective non-pharmacological method in alleviating pain associated with the neonatal intramuscular injection of vitamin K.

Keywords: Intra- Muscular Injection; Neonate; Pain Management; Z- Track Technique

INTRODUCTION

Neonates go through a number of painful and invasive nursing procedures that are part of the required neonatal care within their first days of their neonatal life. These procedures may include administering vitamin K supplements (Hand et al., 2022) intramuscularly that help to prevent neonatal haemorrhage, blood sample collection through heel lancet or from a vein, and also intravenous injection or injection of the vastus lateralis muscle (Mohamed et al., 2019). For this group of newborns, adequate postnatal vitamin K intake appears to be essential. In order to prevent haemolytic disease in newborns, vitamin K is frequently administered as a prophylactic after birth (Patel et al., 2022). The phenomenon of pain experienced by neonates as a result of medical procedures has garnered significant concern over the past two decades. On average, a neonate undergoes approximately 7 to 17 medical interventions daily during the initial 14 days postnatally (Sankar et al., 2016).

Research demonstrates that exposure to pain during early childhood is correlated with the manifestation of violent behaviour and self-destructive tendencies during adolescence (Beena et al., 2025). Other consequences of uncontrolled or unmanaged pain stimuli include permanent interruption to cognitive growth and possibly neonates’ development rate due to interfering with the brain growth flexibility and thereby interference in subsequent pain responses (Taghinejad & Suhrabi, 2025). Managing pain for control thereby should be part of the neonate routine care performed during nursing and medical procedures (Lago et al., 2025).

In recent years, the importance of non-pharmacological approaches has increased due to the potential side effects of pharmacological methods (Al-Shammiry & Al-Fayyadh, 2024), such as respiratory depression, apnoea, and bradycardia. As a result, nursing research has concentrated on these methods. While pain experienced by newborns after normal vaccination is not considered a symptom of disease, it has been suggested that non-pharmacological pain relief techniques are preferable. Non-pharmacological treatment options include things like using skin tap techniques to distract from pain (Sahoo et al., 2025), listening to music (Brown et al., 2022), and therapeutic applications of heat and cold (Güngör & Öztürk Şahin, 2020). The ZTT method is deemed as one of the prevalent non-pharmacological strategies and techniques that are utilised while administering injections (Said & Shehata, 2016). The way this technique works is by retracting the skin by using the non-dominant hand on the injection site of the muscle approximately 2.5 cm to 3.5 cm to the lateral side, then inserting the tip of the needle into the muscle at a ninety-degree angle, and the skin is immediately released to return to its normal status once the needle is pulled from the muscle following the drug injection (Baş & Keçeci, 2023). Considering the Z technique usage in practice is not very common, but there is evidence supporting the technique's effectiveness and recommending its routine use (Sah & Maskey, 2020).

Assessment and management of pain should be taken into account, as inappropriate assessment may complicate the process of pain management (Bachi & AL-Fayyadh, 2022). In one article, ‘The Fifth Vital Sign: Implementation of Neonatal Infant Pain Scale’ describes a Californian hospital’s implementation of NIPS and the education provided to nurses and its utilisation in clinical practice (Attar et al., 2022; Ismail & Ali, 2025). NIPS was found to be an accurate tool in assessing pain and easy in application by nurses (Bhattacharya & Batra, 2020). Reviewing the previous literature provided evidence on the effect of the ZTT on adult patients, such as in a study conducted by Yilmaz et al. (2016), which concluded that using the ZTT is effective in reducing pain during intramuscular injection for adult patients. Another study by Tambunan and Wulandari (2015) utilised the ZTT air locking technique and found it effective in reducing pain in intramuscular injections. However, no study was conducted on the paediatric population to determine the efficacy of the technique, and this explains the purpose of conducting this study to address the knowledge gap and generate evidence-based practice to be used by paediatric nurses performing intramuscular injections of neonates.

Alternative Hypothesis: (H1)

Term neonates administered intramuscular injections using the ZTT will experience a marked decrease in pain scores as opposed to those not receiving the technique.

METHODOLOGY

Study Design and Trial Registration

The study was a prospective randomised controlled clinical trial with a parallel group design. The trial was registered at https://clinicaltrials.gov/study/NCT06793618 with registration number NCT06793618. The study took place between November 25th 2024 to January 24th, 2025. The study adhered to the guidelines outlined in the Consolidated Standard of Reporting Trials (CONSORT 2010 checklist).

Study Setting

This research took place in Al Muthanna governorate / Al Muthanna health directorate, at the Feminine and Children Educational Hospital in the post-natal ward. Neonates delivered by caesarean section are transferred to the postnatal ward, which is a part of the neonatal intensive care unit, for assessment and stabilisation before being scheduled to be returned to their mothers/legal guardians, during which the neonate receives various procedures, including intramuscular injections of hepatitis B vaccine and vitamin K injection, making it the place where neonates receive their first intramuscular injection.

Study Sample

The study was carried out on healthy term neonates admitted to the postnatal ward immediately after delivery by caesarean section. A simple random sample technique was utilised to select neonates to be part of the study. This random technique provides the advantage of removing any bias in the sample selection (Lim & In, 2019). After the newborn babes were put in the incubator, the paediatrician examined the newborns and provided written orders for nurses regarding injecting the neonates with vitamin K supplementation intramuscularly. Those neonates were the target of this study. The website random.org was used to generate the randomisation sequences for allocation into study or control groups. The sample size was determined using G power analysis (G*Power v3.1.9 software) and was eighty) term neonates allocated into the study and control groups. Figure 1 shows the sample enrolment flowchart.

Figure 1: Study Sample Flow Chart

Sample Size Determination

Power analysis was performed using the G*Power (v3.1.9) software adopted by Grove and Grey (2019) to determine the sample size. The effect size was found to be Cohen’s w = 0.4, calculated based on previous research conducted by Kaya and Zengin (2023) with a probability error of α

= 0.05 and β = 0.10. A sample size of 70 neonates would be sufficient to detect significances in the sample. Considering withdrawals from the study and possible bleeding after injection, the total sample size was 80 healthy term neonates.

Criteria for Selection of the Study Sample Inclusion Criteria

The researchers targeted healthy neonates delivered between the 37th and 42nd weeks of gestation through caesarean section, who weighed between 2500 and 3500 grams and achieved an Apgar score of 8 or more. Those who did not receive any analgesics or any invasive procedures prior to the intramuscular injection of vitamin K. This was due to the possibility of interfering with pain perception in neonates and thus affecting pain measurement (Lindbeck et al., 2023).

Exclusion Criteria

Neonates suffering from any congenital anomalies, having low birth weight, considered preterm, delivered normally (normal vaginal delivery), and also those who received hepatitis B vaccination prior to transfer to the postnatal ward were not included in the study.

Data Collection Tools Newborn Clinical Data Form

The form consisted of three items reported by the observer (nurse), including the newborn’s gestational age in weeks, gender, and birth weight in grams.

Neonatal/infant Pain Scale (NIPS)

A scale developed specifically for newborn infants. The scale consists of 6 criteria (face expression, cry, patterns of breathing, leg and arm movements, and arousal status) and is recommended for use for pain assessment in children less than 1 year old.

The following explains the scoring system using this scale:

The criterion (crying) has 3 scorings (0-1-2); however, all the other criteria have 2 scorings (0- 1). A score of zero represents no pain, 1-2 is considered mild pain, 3-4 is moderate pain, and 5- 7 is severe pain.

Study Instrument Validity/Reliability

The early questionnaire was presented to a panel of 12 experts who had more than 10 years of experience in nursing science to assess for clarity and whether the questionnaire is good enough to achieve the desired goals of the study. Changes were limited to demographic items only.

Lawrence et al. (1993) developed NIPS, and the validity and reliability tests were conducted by Kanbur et al. (2021) in their Turkish study. The values of the Cronbach test in the original study ranged from 0.87 to 0.95. It was reported that the Turkish study to obtain the validity and reliability for the NIPS scale resulted in a range from 0.83 to 0.86 using the Cronbach Alpha coefficient test.

Procedures

In the postnatal ward where the study was conducted, routine care (cleaning, drying, nasal care) is carried out under a radiant heater. Vitamin K is administered during the first few hours of life. The injection procedure protocol is provided in table 1. The newborn stays in the postnatal ward until they are actively feeding and show no sign of distress; then they are delivered to their mother/legal guardians (father, grandmother). In this study, the newborn pain was evaluated by NIPS, and pain was evaluated at one timepoint during the Intramuscular (IM) Injection procedure. In the study, neonates who received ZTT during the IM injection were included in the experimental group, while those who received the IM injection with the routine method were included in the control group. All interventions to the newborns in the control group were performed under a radiant heater. All newborns should receive vitamin K prophylaxis, as it has been proven that oral and intramuscular prophylactic vitamin K given after birth are effective for preventing classical Haemorrhagic Disease of the Newborn (HDN) (Jullien et al., 2021). Vitamin K deficiency in an infant can cause bleeding known as HDN or Vitamin K Deficiency Bleeding (VKDB) (Clarke et al., 2015). When the IM route is chosen with standard precautions in the anterolateral thigh, the risk of local hematoma, infection, and neuromuscular damage at the injection site is very low (Jullien et al., 2021).

Table 1: Vitamin K Intramuscular Injection Protocol

Intervention Group

During the administration of the injection, the neonate was in a supine position, the position of his/her legs was normally flexed, and the ZTT was adopted when administering the injection. During injection, the skin was pulled laterally, and, thereby, the cutaneous and subcutaneous tissues were moved by approximately 1 to 2 cm. The researcher who injected the drug used the nondominant hand to displace the cutaneous and subcutaneous tissues, and a co-observer recorded the pain score after needle withdrawal on the neonatal clinical data form.

Control Group

During the administration of the injection, the neonate was in a supine position, the position of his/her legs was normally flexed, and the injection was administered using the routine method. During the routine injection technique practice, the skin was not pulled laterally. A co-observer (nurse) recorded the pain score on the neonatal clinical data form.

Data Collection

Before starting the study, the purpose of the study, the content of the forms, the interventions and how the data obtained in the study will be used were explained to the primary carer of the newborns, and then their verbal and informed consent was obtained. Explaining to the primary carer that participation and withdrawals are their choice and without any consequences and that participation is without any sentiments or rewards.

Only newborns from parents who gave their informed consent were included in the study. The nurse who performed the injection procedure was a bachelor's degree paediatric nurse who had 15 years of experience handling neonates in the neonatal wards, which makes them most suitable to perform the procedure, ensuring the successfulness of the procedure and the intervention, and also guaranteeing the safety and avoiding any unnecessary injury to the neonate.

The other academic nurse, who is the observer, had previously participated in clinical trials assessing pain levels using various outcome measurements and had previous training with using the neonatal/infant pain scale to ensure the appropriate assessment of the outcome, providing the best health outcome by accurately performing the assessment process, achieving the best health results and avoiding any bias.

Blinding/Masking

In randomised clinical trials, using a blinding method is considered part of the gold standard of the RCT methodological strength (Saltaji et al., 2018). This was done by putting a foldable medical privacy screen between the neonate in the incubator and the observer nurse while performing the injection, and immediately after needle withdrawal, the observer removes the privacy screen and starts recording the pain score without knowing what the intervention applied by the first nurse was (ZTT or standard technique).

Data Analysis

The Statistical Package for Social Sciences (SPSS) version 27 was used for statistical analysis. Categorical data were represented as numbers and percentages, and numerical data as mean and standard deviation. Normal distribution was tested using the Shapiro-Wilk test and graphical analyses. Mann Whitney The U test was used for comparisons between two groups of non- normally distributed quantitative variables. Pearson's chi-square test was used to evaluate categorical data. Statistical significance was accepted to be p < 0.05.

Ethical Consideration

The study received ethical confirmation from the Committee of Scientific Research (CSR) at the College of Nursing, University of Baghdad, Iraq, with reference number REF-37 on 6th November 2024.

RESULTS

Table 2: Distribution of Demographic Variables for Neonates (n= 80)

Freq.=frequency; %= percentage; X2= chi-square; T= student t test; p value <0.05 = significant

Table 2 shows that more than half (55.5%) of neonates in the study group and half (50%) in the control group had 38 weeks of gestational age. It was also found that more than half (60%) of the study group were males, and slightly more than half (52.5%) of the control group were females. The table shows that the mean birth weight in the study group was 2947.5±288.7 and in the control, group was 2875.7 ± 255.7. However, there were no statistically significant differences between the study and control groups regarding gestational age, sex, and birth weight, indicating similarity between groups.

Table 3: Association of Injection Technique with the Pain Level of the Neonates (n= 80)

Freq.=frequency; %= percentage; NIPS= Neonatal/ infant pain scale

Table 3 indicates there were 11 neonates (27.5%) who had no pain in the intervention group. Twenty-one neonates (52.5%) had moderate pain when the ZTT was applied, and the remaining eight (20%) suffered severe pain. Contrary to the findings in the interventional group, 23 (57.5%) had severe pain, 15 (37.5%) had moderate pain, and only 2 (5.0%) had mild pain in the control group.

Table 4: Total Mean Score of Pain for Newborn in Study and Control Groups with Mean Differences for Neonates (n= 80)

SD=standard deviation; Min=minimum; Max= maximum; p < 0.01**=highly significant; a= calculated using Mann-Whitney U

Table 4 clarifies that the mean pain score in the ZTT group is 3.28 ± 1.08, and the pain score is

4.53 ± 1.26 among the control group. The table shows a statistically significant difference between the groups (Mean Difference = -1.25, P = 0.000), indicating a very large difference between the ZTT and the conventional IM injection method. Similarly, the median of the Neonatal Infant Pain Scale score of the neonates in the experimental group (3) was lower than that of the control group (5), and this was found to be statistically and clinically significant (P < 0.001).

DISCUSSION

Pain management is a primary responsibility of nurses working in neonatal wards. Various non- pharmacological interventions have demonstrated efficacy in preventing and relieving pain in infants undergoing painful procedures (Lago et al., 2025). It is important that these methods are effective, low-risk and cost-effective. Pain response in infants is affected by factors such as gestational week, sex, and weight (Nugrawati et al., 2024). In this study no statistically significant difference was found between the study groups in terms of those factors, and hence the groups were similar (p> 0.05). From the researcher perspective, factors such as gestational age, sex, and weight affect infants’ response to pain so that the researchers focused on the homogenous distribution of these characteristics, which are thought to affect IM pain levels, thus contributing to eliminating these confusions. These findings go with the findings of the study conducted by Elshahat et al. (2023), who found in their study the effect of cold and heat on pain of pentavalent vaccination and reported that no significant differences were noted between the study and control groups with regards to sex, birth weight, nutrition status and gestational age.

In the study findings reported on table 3, the pain level for the experimental group was tested to be significantly lower than the control group. This study finding is of similarity to a study conducted by Shamsalinia et al. (2024) on the facilitated tucking effect on reducing pain using the same outcome measurement as this research, and the study found that neonates in the study group have a lower Neonatal/Infant Pain Scale mean score than those in the control group. Another study conducted by Saji et al. (2024) on adult patients provided evidence on the difference between the pain levels of using ZTT and the standard method, which clarified that the majority of the study group had moderate levels of pain in the experimental group, while the control group sample had moderate to severe pain levels.

Regarding the mean score of pain as shown in table 4, applying the ZTT during IM injection resulted in a significantly lower mean pain score compared to neonates who underwent vitamin K injection using the routine method. This goes with a study by Elsaid and Abdelkhalek (2019) that concluded the usage of the ZTT method resulted in low pain scores when used during IM injections compared to using the standard method during intramuscular injections. A study by Kara and Güneş (2016) had similar results, which found that less pain is noted with the ZTT use during IM injection. Moreover, another study that was conducted in Turkey by Yilmaz et al. (2016) found that pain intensity was reduced when the IM sodium diclofenac was injected by using the ZTT. These results are also supported by Tambunan and Wulandari (2015), who illustrated that both the ZTT and air-lock methods resulted in less painful IM injections compared to the standard technique.

Various non-pharmacological methods have been proven to be effective in reducing intramuscular-associated pain in the paediatric population, and these include shot blockers (Yilmaz et al., 2024), kangaroo mother care (Fallah et al., 2017), music (Rossi et al., 2018), oral sucrose (Imani & Moradi, 2019), and breastfeeding (Kaur et al., 2024). Those options are cost- effective and are easy to use, and their actions and effectiveness in reducing pain have been proven during intramuscular injections. Better health-related outcomes regarding patients’ experiences can be provided by employing non-pharmacological approaches (de Alencar et al., 2024; Gilbertson et al., 2023).

Health care providers, and especially nurses, realised their important role in pain management for patients (Fahd & Shawq, 2023). This is related to nurses’ ability to guide patients regarding alleviating pain through non-pharmacological techniques and also supporting them emotionally and cognitively. Hence, nurses have a major role in pain management for patients according to the planned treatment plan, thus contributing to patient safety (Albugami et al., 2023).

Limitations

Considering the study took place in one postnatal ward, the results are limited to those neonates only. Another limitation is that the study did not include hepatitis B vaccine injection. also, the study included only term infants limited to vitamin K injections.

CONCLUSION

In the study, the researchers have reached the conclusion that the ZTT application during IM injections for neonates had an alleviating effect on the NIPS scores. Low mean pain scores in the ZTT indicating the effectiveness of using this technique. Therefore, this strategy for pain reduction can be utilized by nurses during standard injection practice and is considered cost- effective during intramuscular injections of neonates.

The study can include neonates going through vaccination, such as the hepatitis B vaccine birth dose. The effectiveness of the ZTT can be compared with the air-lock technique for neonatal injection. Future similar studies can be conducted on older children during pentavalent vaccination and on medications administered muscularly for ill patients.

Conflict of Interest

No conflicts of interest are declared by the researchers.

ACKNOWLEDGEMENT

The authors are thankful to the medical and nursing staff for supporting this study. Also, the authors express gratitude towards the infants’ legal guardians for their consent and participation.

REFERENCES

Albugami, N. F. H., Albugami, F. F. H., Albuqmi, H.F. H., Al-bugomi, M. F., Alnfeai, A. K. M., & Alqahtani, R. S. A. (2023). Evaluation of nurses’ practice related to injection safety. Journal of Survey in Fisheries Sciences, 10(6). https://doi.org/10.53555/sfs.v10i6.2253

de Alencar, I. G. M., dos Santos Dantas, J. K., de Araújo, S. C. M., de Lima Fernandes, T. E., de Araújo, P. L. O., da Costa, A. B., ... & de Oliveira, J. S. A. (2024). Non-pharmacological therapies for pain management in paediatric intensive care units: a protocol for a scoping review. BMJ Open, 14(2), e074952. https://doi.org/10.1136/bmjopen-2023-074952

Al-Shammiry, S., & Al-Fayyadh, S. (2024). Manual pressure verses shot blocker in reducing intramuscular injection-related pain: A comparative randomized controlled trial. Bahrain Medical Bulletin, 46(1). https://www.bahrainmedicalbulletin.com/March_2024/Abstracts/BMB- 23-512%20ABSTRACT.pdf

Attar, W. M. A. A.-, Hattab, W. A. A., & Abdulghan, M. F. (2022). Nurses’ Knowledge and Attitude about Intramuscular Injection (LML). Pakistan Journal of Medical and Health Sciences, 16(3), 1078–1081. https://doi.org/10.53350/pjmhs221631078

Bachi, G. E., & AL-Fayyadh, S. (2022). Determination of procedural pain intensity among Critically Ill patients: Using Behavioral Pain Scale (BPS). Journal of Contemporary Medical Sciences, 8(4), 264–269. https://doi.org/10.22317/JCMS.V8I4.1260

Baş, D. Y., & Keçeci, A. (2023). Barriers of nurses’ about ‘Z-Track Method’ which is used in intramuscular injections applications. Akdeniz Hemşirelik Dergisi, 2(1), 1–9. https://doi.org/10.59398/ahd.1123694

Beena, M., Gauthami, M., & Singh, G. (2025). Effectiveness of breastfeeding on pain among infants undergoing intramuscular vaccination. RV Journal of Nursing Sciences, 4(1). https://rvjns.rvcn.edu.in/wp-content/uploads/2025/01/4-Ms.-Beena.pdf

Bhattacharya, R., & Batra, B. (2020). Effect of Helfer skin tap technique and expressed breast milk on response to pain among neonates during intramuscular injection. International Journal of Paediatrics and Geriatrics, 3(1), 158–164. https://doi.org/10.33545/26643685.2020.v3.i1c.75

Brown, S., Banks, K., Danelyan, H., & Tachdjian, R. (2022). Physiological effects of music therapy in neonatal intensive care setting observational study. Academic Journal of Pediatrics & Neonatology, 11(3). https://doi.org/10.19080/ajpn.2022.11.555867

Clarke, P., Mitchell, S. J., & Shearer, M. J. (2015). Total and differential phylloquinone (Vitamin K1) intakes of term infants from all sources during the neonatal period. Nutrients, 7(10), 8308– 8320. https://doi.org/10.3390/nu7105393

Elsaid, R., & Abdelkhalek, W. (2019). The effect of shot blocker and Z – track techniques on reducing the needle pain and anxiety associated with intramuscular injection. International Journal of Nursing Didactics, 09(12), 31–38. https://doi.org/10.15520/ijnd.v9i12.2777

Fahd, M. M., & Shawq, A. H. (2023). The effects of planned program on nurses’ practices for intramuscular injection among pediatric. Pakistan Heart Journal, 56(2), 530–536. https://www.pkheartjournal.com/index.php/journal/article/view/1409

Fallah, R., Naserzadeh, N., Ferdosian, F., & Binesh, F. (2017). Comparison of effect of kangaroo mother care, breastfeeding and swaddling on Bacillus Calmette-Guerin vaccination pain score in healthy term neonates by a clinical trial. The Journal of Maternal-Fetal & Neonatal Medicine, 30(10), 1147-1150. https://doi.org/10.1080/14767058.2016.1205030

Gilbertson, C. J., Rasekaba, T., & Blackberry, I. (2023). Exploring the feasibility of using virtual reality as a nonpharmacological intervention to alleviate patient fear of needles during medical treatment: A study protocol. Journal of Perioperative Nursing, 36(3). https://doi.org/10.26550/2209-1092.1268

Grove, S., & Gray, J. (2019). Understanding Nursing Research (7th ed.). Elsevier.

Güngör, T., & Öztürk Şahin, Ö. (2021). Analysis of two non-pharmacological pain management methods for vaccine injection pain in infants: A randomized controlled trial. Agri: The Journal of the Turkish Society of Algology, 33(1), 15-22. https://doi.org/10.14744/agri.2020.54289

Hand, I., Noble, L., Abrams, S. A., Cummings, J. J., Aucott, S. W., Goldsmith, J. P., Hand, I. L., Puopolo, K. M., Adams-Chapman, I. S., Kaufman, D. A., Martin, C. R., & Couto, J. (2022). Vitamin K and the Newborn Infant. Pediatrics, 149(3). https://doi.org/10.1542/PEDS.2021- 056036/184866

Imani, A., & Moradi, F. (2019). Comparison of the effects of oral sucrose 30% and 50% on the pain of injection of hepatitis b vaccine in newborns. Zahedan Journal of Research in Medical Sciences, 22(1). https://doi.org/10.5812/zjrms.91557

Ismail, A., & Ali, A. (2025). Neonatal nurses’ knowledge and use of non-pharmacological pain management interventions in Saudi Arabia. Journal of Neonatal Nursing, 31(1), 210–215. https://doi.org/10.1016/j.jnn.2024.08.002

Jullien, S., Huss, G., & Weigel, R. (2021). Supporting recommendations for childhood preventive interve ntions for primary health care: Elaboration of evidence synthesis and lessons learnt. BMC Pediatrics, 21. https://doi.org/10.1186/s12887-021-02638-8

Kanbur, B. N., Mutlu, B., & Salihoğlu, Ö. (2021). Validity and reliability of the Neonatal Infant Acute Pain Assessment Scale (Nipas) in Turkish: Prospective study. Sao Paulo Medical Journal, 139(4), 305–311. https://doi.org/10.1590/1516-3180.2020.0721.R1.23122020

Kara, D., & Güneş, Ü. Y. (2016). The effect on pain of three different methods of intramuscular injection: A randomized controlled trial. International Journal of Nursing Practice, 22(2), 152– 159. https://doi.org/10.1111/ijn.12358

Kaur, H., Charan, G. S., Kaur, R., Narang, G. S., & Khurana, M. S. (2024). Comparison of breastfeeding, music therapy, and oral sucrose’s impact on pain relief among infants during pentavalent vaccination. Journal of Education and Health Promotion, 13(1). https://doi.org/10.4103/jehp.jehp_860_23

Kaya, L., & Zengin, N. (2023). The effect of postpartum skin-to-skin contact on the pain of the first intramuscular injection to the Newborn: A randomized controlled trial. Journal of Neonatal Nursing, 29(6), 862–868. https://doi.org/10.1016/j.jnn.2023.07.013

Lago, P., Garetti, E., Savant Levet, P., Arenga, I., Pirelli, A., Frigo, A. C., & Merazzi, D. (2025). Current practices in neonatal pain management: A decade after the last Italian survey. Italian Journal of Pediatrics, 51(1), 48. https://doi.org/10.1186/s13052-025-01896-x

Lawrence, J., Alcock, D., McGrath, P., Kay, J., MacMurray, S. B., & Dulberg, C. (1993). The development of a tool to assess neonatal pain. Neonatal Network: NN, 12(6), 59–66. https://pubmed.ncbi.nlm.nih.gov/8413140/

Lim, C.-Y., & In, J. (2019). Randomization in clinical studies. Korean Journal of Anesthesiology, 72(3), 221–232. https://doi.org/10.4097/kja.19049

Lindbeck, G., Shah, M. I., Braithwaite, S., Powell, J. R., Panchal, A. R., Browne, L. R., Lang, E. S., Burton, B., Coughenour, J., Crowe, R. P., Degn, H., Hedges, M., Gasper, J., Guild, K., Mattera, C., Nasca, S., Taillac, P., & Warth, M. (2023). Evidence-Based guidelines for prehospital pain management: recommendations. Prehospital Emergency Care, 27(2), 144–153. https://doi.org/10.1080/10903127.2021.2018073

Elshahat, H. T. M., Farg, H. K., & Mohammed, E. G. F. (2023). Effect of local heat and cold application for pentavalent vaccine injection pain in infants. Assiut Scientific Nursing Journal, 11(37), 131-140. https://doi.org/10.21608/asnj.2023.205771.1569

Mohamed, F. A., El-Bana, S. M., Mohamed, E. A. E., & Abolwafa, N. F. (2019). Effect of educational program on pediatric nurses' knowledge and practice regarding selected nonpharmacological techniques to relive pain in neonates. Journal of Neonatal Nursing, 25(6), 285-292. https://doi.org/10.1016/j.jnn.2019.04.007

Nugrawati, N., Wijaya, A., & Adam, A. M. (2024). Facilitated Tucking: A simple technique to reduce infant pain during HB-0 Vaccination. Journal of Social Science Research, 4. https://j- innovative.org/index.php/Innovative/article/view/17413/11749

Patel, D. V., Soni, S. N., Shukla, V. V., Phatak, A. G., Shinde, M. K., Nimbalkar, A. S., & Nimbalkar, S. M. (2022). Efficacy of skin-to-skin care versus swaddling for pain control associated with vitamin k administration in full-term neonates: A randomized controlled trial. Journal of Tropical Pediatrics, 68(4). https://doi.org/10.1093/tropej/fmac052

Rossi, A., Molinaro, A., Savi, E., Micheletti, S., Galli, J., Chirico, G., & Fazzi, E. (2018). Music reduces pain perception in healthy newborns: A comparison between different music tracks and recoded heartbeat. Early Human Development, 124, 7–10. https://doi.org/10.1016/j.earlhumdev.2018.07.006

Sah, S. R., & Maskey, S. (2020). Knowledge of intramuscular injection among the nurses of a teaching hospital. Journal of Chitwan Medical College, 10(1), 40–43. https://doi.org/10.3126/jcmc.v10i1.28069

Sahoo, S. P., Das, N., Sahoo, P., & Bhaktiswarupa, S. (2025). Effectiveness of Helfer skin tap technique on pain among infants undergoing intramuscular vaccination – A randomized controlled trial. F1000Research, 14, 205. https://doi.org/10.12688/f1000research.159819.1

Said, O., & Shehata, M. H. (2016). Effects of Helfer skin tapping and z-track techniques on pain intensity among hospitalized adult patients who receiving intramuscular injection. International Journal of Novel Research in Healthcare and Nursing, 3, 77–94.

Saji, J., Margaret, N. C., & Evency, A. R. (2024). Effectiveness of Z track technique versus standard technique on pain perception during intramuscular injection among patients underwent orthopaedic surgery. Research Review International Journal of Multidisciplinary, 9(5), 235-250. https://doi.org/10.31305/rrijm.2024.v09.n05.029

Saltaji, H., Armijo-Olivo, S., Cummings, G. G., Amin, M., da Costa, B. R., & Flores-Mir, C. (2018). Influence of blinding on treatment effect size estimate in randomized controlled trials of oral health interventions. BMC Medical Research Methodology, 18(1), 42. https://doi.org/10.1186/s12874-018-0491-0

Sankar, M. J., Chandrasekaran, A., Kumar, P., Thukral, A., Agarwal, R., & Paul, V. K. (2016). Vitamin K prophylaxis for prevention of vitamin K deficiency bleeding: a systematic review. Journal of Perinatology, 36(S1), S29–S35. https://doi.org/10.1038/jp.2016.30

Shamsalinia, A., Fotokian, Z., Jannat Alipour, Z., Zahedpasha, Y., & Mohammadkhah, F. (2024). Effects of white noise sound on the severity of muscle vaccination pain in children under two years Iran. Iran Journal of Child Neurology, 18(2), 113–125. https://doi.org/10.22037/ijcn.v18i2.38746

Taghinejad, H., & Suhrabi, Z. (2025). Effect of non-pharmacological intervention sweet-tasting solution on pain in term infants who receive vaccination. Medical Sciences Journal of Basic Research in Medical Sciences, 12(1), 43–48. http://jbrms.medilam.ac.ir/article-1-856-en.html

Tambunan, E. H., & Wulandari, I. S. (2015). Utilizing Z-track air lock technique to reduce pain in intramuscular injections. Jurnal NERS, 10(1), 112. https://doi.org/10.20473/jn.V10I12015.112-117

Yilmaz, D. A., Akça, S. O., & Kendirci, H. N. P. (2024). Shotblocker or cold application; Which one is more effective in reducing anxiety and pain associated with the intramuscular injection in children? A Randomized Controlled Trial. Bezmialem Science, 12(1), 98–106. https://doi.org/10.14235/bas.galenos.2023.75010

Yilmaz, D., Khorshid, L., & Dedeoǧlu, Y. (2016). The effect of the z-track technique on pain and drug leakage in intramuscular injections. Clinical Nurse Specialist, 30(6), E7–E12. https://doi.org/10.1097/NUR.0000000000000245