The researcher will conduct the Nurse-Led Education Programme on IPC for one experimental group through face-to-face/onsite delivery.

The researcher will conduct the Nurse-Led Education Programme on IPC for another experimental group through online platform delivery.

Participants in the control group will continue their usual practice without receiving any intervention and materials until the post-intervention assessment at six months. After that, the researcher will provide the online or onsite programmes and distribute all materials.

The programme was designed to enhance CCWs' IPC knowledge and attitudes through lectures, interactive discussions, information sharing, and Q&A sessions. It also aims to improve their IPC practices and self-efficacy through demonstrations, role-playing exercises, and a work assignment focused on IPC self-monitoring.

The programme includes five educational sessions totalling 12 hours, along with one session for work assignment on daily self-monitoring of IPC practices over five days. The educational sessions cover the following topics:

1. General concepts of infectious diseases
2. Vaccination
3. Standard precautions: The use of personal protective equipment, environmental cleaning and disinfection, handling food and feeding, and waste management
4. Standard precautions: Hand hygiene
5. Common infectious diseases in DCCs and management.

This questionnaire was adapted from an existing validated tool, the knowledge of preventive behaviors for communicable diseases questionnaire. It was developed based on the Disease-Free Child Care Centers Policy from the Department of Disease Control, Thailand Ministry of Public Health, to assess Thai CCWs. The original questionnaire consists of 15 dichotomous questions. The item objective congruence (IOC) was evaluated by five experts, resulting in a score of 0.744, and internal consistency was assessed with a KR-20 of 0.73 (n = 30).

In this study, the researchers added five questions regarding the knowledge of using personal protective equipment, handling food and feeding, and managing waste. Therefore, the final version of this questionnaire consists of 20 dichotomous questions. The total score will be calculated by summing the correct responses, with higher scores indicating greater levels of IPC knowledge.

This questionnaire was adapted from an existing validated tool, the attitudes of preventive behaviors for communicable disease questionnaire. It was developed based on the Disease-Free Child Care Centers Policy from the Department of Disease Control, Thailand Ministry of Public Health, to assess Thai CCWs. The original questionnaire consists of 15 items with five-point Likert scales. The IOC was evaluated by five experts, resulting in a score of 0.744, and internal consistency was assessed with a Cronbach's α of 0.71 (n = 30).

In this study, the researchers removed questions that were outside the conceptual definition and added questions regarding beliefs, perceptions, and feelings about the importance and necessity of IPC measures. The final version of this questionnaire still consists of 15 items, including both positive and negative statements, with five-point Likert scales. The total score will be calculated, with higher scores indicating more positive attitudes toward IPC.

This questionnaire was adapted from an existing validated tool, the preventive behaviours for communicable disease questionnaire. It was developed based on the Disease-Free Child Care Centers Policy from the Department of Disease Control, Thailand Ministry of Public Health, to assess Thai CCWs. The original questionnaire consists of 15 items with five-point Likert scales. The IOC was evaluated by five experts, resulting in a score of 0.744, and internal consistency was assessed with a Cronbach's α of 0.71 (n = 30).

In this study, the researchers added five questions regarding practice of vaccination monitoring, the use of personal protective equipment (PPE), handling food and feeding, and waste management. Therefore, the final version of this questionnaire consists of 20 items with five-point Likert scales. The total score will be calculated, with higher scores indicating higher levels of IPC practices.

This questionnaire was translated from an existing validated tool, the hand hygiene intention questionnaire. It was originally developed based on the Theory of Planned Behavior and identified through focus group discussions with caregivers and managers of DCCs to assess hand hygiene intention among CCWs in the Netherlands. The questionnaire consists of 2 items with seven-point Likert scales. The internal consistency was measured with a Cronbach's α of 0.90 (n = 350). The total score will be calculated, with higher scores indicating greater levels of hand hygiene intention.