NeoDeco is a pragmatic, multicenter, parallel-group, cluster-randomised hybrid effectiveness-implementation trial designed to evaluate the impact of implementing optimised Kangaroo Care (KC) at the unit level compared to standard care in high-technology neonatal units. The trial includes a baseline period, a wash-in phase, and a staggered randomisation approach. The primary focus of the NeoDeco study is on high-risk preterm infants born at less than 32 weeks' gestational age, a population particularly vulnerable to hospital-acquired infections and sepsis during their initial hospital stay. By investigating hospital-acquired infections specifically, the study targets the period during which optimised KC practices are likely to have the most significant impact.

NeoDECO trial is a cluster-randomised study involving up to 24 neonatal units (clusters) across five European countries: Switzerland, Italy, Greece, Spain, and the United Kingdom. Each participating neonatal unit constitutes a cluster, with the intervention implemented at the unit level. The study is structured into two staggered. Within each stagger, sites are randomised 1:1 to either the intervention arm or control arm (standard care).

Control Arm (Standard Care): Sites randomised to the control arm will continue with current routine practices, which might include kangaroo care (KC), skin-to-skin contact (StSC), infection prevention and control measures, and the treatment of severe infections or neonatal sepsis. While KC is already part of routine care in all participating units, there are no structured efforts in place to ensure adherence to international best practice guidelines.

Intervention Arm (Optimised KC): Sites in the intervention arm will implement optimised KC in line with internationally recognised best practice recommendations. The intervention is comprised of two key components:

Component 1: Skin-to-Skin Contact (StSC) for Optimised KC This component defines the desired frequency, duration, and initiation timing of early, repeated, and sustained StSC that characterise optimised KC in high-technology neonatal environments where KC is already offered.

Component 2: Implementation Support This component focuses on engaging clinical staff responsible for KC delivery. Implementation support includes training, ongoing support, and tools to embed optimised KC into routine practice. The goal is to facilitate sustained practice change through staff empowerment and structured implementation strategies.

Following randomisation, sites allocated to the intervention arm will undergo an intervention period of up to 10 months. All sites-regardless of allocation-will collect clinical data and biological samples from all consented high-risk infants present in the unit on the day of the assessment. The collected samples will be analyzied centrally and help monitor colonisation and infection patterns over time, with particular focus on the incidence of hospital-acquired infections.

To evaluate the fidelity and quality of the intervention delivery, one representative intervention site from each participating country will be selected for enhanced data collection and engagement with the implementation team. These sites will participate in more detailed assessments related to: fidelity of intervention delivery, implementation strategies used, acceptability, appropriateness, and feasibility of optimised KC.

At the conclusion of the study, all control sites will receive full support and training to implement optimised KC using the tested implementation strategies. This ensures equitable access to the intervention benefits across all participating units and supports the potential scale-up of optimised KC practices beyond the trial period.

INCLUSION CRITERIA

1. Site level

1a. Neonatal unit that provide routinely cares for extremely premature infants (<28 weeks' gestation).

1b. Minimum capacity of 12 beds.

1c. Access to a -70 to -80°C freezer for storage of research samples

1d. Willing to implement optimised KC if allocated to the intervention group.

1e. Willing to commit to offering the minimum expected target duration or an increase of 50% if neonatal unit is already offering >67% of the minimum expected target duration, if allocated to the intervention arm.

1f. Prepared to implement NeoIPC surveillance.

1. g. Adequate resources and expertise and approvals from relevant Research Ethics Committees, as appropriate.
2. Infant level

2a. All high-risk infants (born at <32 weeks' gestation) admitted to participating neonatal units, regardless of complexity of care, anticipated hospitalisation duration, room type, or whether admitted directly after birth.

EXCLUSION CRITERIA 1 Site level

1. a. Participation in other research that could directly influence the study intervention or outcomes.
2. a. Average StSC duration already exceeding 18 hours per day.
3. a. Anticipated major changes in resistant bacterial colonisation pressure during the study

2 Infant level 2a. No infant-level exclusion criteria for data collection. We exclude infants from individual data and sample collection if their parents or legal guardians do not provide written informed consent. These infants contribute to cluster-aggregated outcomes.