Abstract
-
Purpose
Education on infant safe sleep practices has been known to reduce the risk of sleep-related sudden unexpected infant death. Since sleep environments may vary across sociocultural contexts, infant safe sleep education needs to reflect specific sociocultural settings. This study aimed to develop an educational Protocol for Infant Safe Sleep (PISS) for primary caregivers in Korea that considers parenting behaviors and cultural characteristics.
-
Methods
This study was conducted in three key methodological steps: (1) retrieval, defining, and systematic classification of PISS content; (2) the structural formulation of the content as an educational protocol; and (3) content validation. For the first step, a literature review was conducted, along with an analysis of educational materials from institution websites related to infant safe sleep and online parenting communities. Field observations were also conducted to identify relevant Korean culture characteristics. Based on these findings, the PISS was developed. Content validity index was assessed by six professionals, and the results were reflected into the educational program.
-
Results
The PISS intervention provided an educational video and booklet and enhanced learning via phone counseling and educational kit, which comprised an illustrated safe sleep sticker and a calendar-style activity diary. The educational content consisted of (1) sleep location, (2) sleep position, (3) bedding, (4) clothes and temperature, and (5) other considerations.
-
Conclusion
This study developed the PISS, an intangible educational intervention based on Korean sociocultural characteristics and specific guidelines for primary caregivers. Future research should evaluate the effectiveness of this program in promoting safe sleep practices.
-
Key words: Child care; Education; Infant; Program development; Sudden infant death
INTRODUCTION
An unsafe sleep environment is associated with an increased risk for sleep-related infant death [
1,
2]. Examples of unsafe sleep environments include bed-sharing, a soft sleep area, prone or lateral sleep position, and high room temperatures [
2,
3]. These conditions are associated with living conditions and rituals at the household or individual level and can be mitigated through educational interventions on sleep practices [
2,
4].
Sleep environments are influenced by cultural practices and customs [
5], making it essential to incorporate these factors when developing infant safe sleep education. In Korea, the lifestyle is predominantly sedentary, and homes are designed with this in mind, featuring the ‘
ondol’ system for underfloor heating. This allows any area of the floor to be used as a sleeping space [
6]. Additionally, Korean culture places a strong emphasis on maintaining warmth, aligning with the ‘yin-yang’ principle of Eastern philosophy [
7]. This concept is particularly emphasized during the postpartum recovery period, where there is a focus on keeping the inside environment warm and limiting cold outdoor exposure [
8,
9]. Conversely, in Western countries like the United States and the United Kingdom, houses are typically heated with air-based systems such as fireplaces and radiators. The floor is often viewed as a cold surface, leading to a preference for beds as the primary sleep environment [
10]. Western culture also encourages placing infants in separate rooms from caregivers to foster independence and autonomy [
11]. Additionally, the practices associated with postpartum recovery seen in Asian cultures are less common in the West [
9]. These cultural distinctions can influence factors related to sleep, such as location, bedding, clothing, and temperature, which could be critical in preventing sleep-related infant death. However, these aspects have not been sufficiently emphasized in generating safe sleep practice related to child rearing practices across cultures [
12].
Developed Western countries like the United Kingdom and the United States have been running national Safe-to-Sleep campaigns since the early 1990s. These efforts have significantly improved the safety of infant sleep environments and contributed to a reduction in the sudden infant death rate in the United States, which decreased from 154.58 per 100,000 live births in 1990 to 92.9 in 2020 [
1]. In Korea, sudden unexplained infant death (SUID) has been the third leading cause of infant mortality for decades including 2023 [
13]. The Centers for Disease Control and Prevention of Korea had once initiated an infant safe sleep campaign around 2007; however, this campaign was not developed into a sustained public education program [
12]. No public promotion has been launched since then and little has been reported on significance of safe sleep practices or their relationship with infant death.
Previous studies on safe sleep education for infant caregivers and healthcare providers have shown that such education enhances their knowledge and confidence, and leads to improved sleep environments for infants [
14]. Limited exposure to infant safe sleep education has been reported to be associated with insufficient knowledge, confidence, and practice levels on infant safe sleep in infant caregivers [
15], child health nurses [
16], and daycare personnel [
17]. This underscores the importance of infant safe sleep practice in any effort to possibly reduce sleep-related infant death, highlighting the educational need for its active promotion in Korean society. This education is particularly significant because it promotes infant health and safe sleep practices. It also has professional significance, as it enables nurses to function as educators and advocates. This study was conducted to develop the educational intervention for infant safe sleep in the context of child rearing practices of Korean grounded in modern East Asian cultures, aiming to support child health nurses in actively performing their roles as educators in clinical and community settings.
METHODS
Ethical statements: This study was approved by the Institutional Review Board of Inha University (IRB No. 221010-3AR). Field observations, including home visits, were conducted during the intervention development phase in accordance with relevant ethical guidelines.
1. Study Design
The methodological design was approached to develop an intangible educational intervention, referred to as the educational Protocol for Infant Safe Sleep (PISS) for primary caregivers to implement for safe sleep practices for their infants in Korea. This study adhered to the Guidance for the Reporting of Intervention Development (GUIDED) reporting guideline [
18].
The development of PISS included three key methodological steps: the first, retrieval, defining, and systematic classification of the PISS content, secondly, the structural formulation of the content as an educational protocol, and the third, content validity of the PISS.
1) Retrieving, defining and classifying the contents of PISS
The initial phase of developing the PISS was to inclusively generate educational contents on infant safe sleep which could be adapted into modern Korean child care cultures. This was achieved through the comprehensive review of the existing literatures in a wide spectrum such as articles or reports from professional institutes, text analysis of conversations from online community for mothers and natural exploration of actual sleep environment and scene by field observations of infant rearing household.
(1) Comprehensive literature review
In the previous study [
19], we have performed a comprehensive review on the research articles, the reports from professional institutes such as the American Academy of Pediatrics (AAP) [
2] or National Forensic Service (NFS) of Korea, and the professional books on SUID [
20,
21]. The summarized findings were the favor to floor sleep or hard mattress even for the cases to use the bed, 89% of SUID with soft bedding in NFS cases, and increased risk with smoking in SUID. These were incorporated in the PISS contents.
(2) Reviewing institutional guidelines
To examine institutional guidelines on infant safe sleep, we compiled a list of national and international organizations specializing in this area, drawing from prior research [
19] and online resources. We selected 17 institutions (five domestic and 12 international) that had specific guidelines available on their websites, reflecting diverse cultural perspectives, and analyzed these materials (
Supplement 1). The guidelines were presented in various formats, including online resources directly on the websites, as well as brochures, leaflets, booklets, and videos. The review of these institutional guidelines focused on factors associated with sudden unexplained infant death as identified in earlier studies [
22]. The educational content covered a range of topics, including the importance of a supine sleeping position, tummy time, a firm bed surface, room-sharing, sleeping in a separate bed, cautious use of swaddling, avoiding soft bedding, choosing appropriate clothing, being wary of high temperatures, promoting breastfeeding, encouraging pacifier use, and warnings against smoking, alcohol, and drug use, along with the importance of regular vaccinations and health checkups, which are further specified in
Supplement 1.
(3) Investigation of information from online communities
To explore caregivers’ perceptions of sleep-related infant death and safe sleep practices, we selected two major nationwide parenting communities operated by the leading Korean search engines, NAVER (
https://www.naver.com/) and Daum (
https://www.daum.net/), which have a combined membership of 3,240,876 and 299,467, respectively. A preliminary investigation of online communities was carried out using 50 posts and 514 comments related to sleep-related infant death and safe sleep that were uploaded over the past 2 months as of October 30, 2021. Our findings indicated that the most frequently discussed topic within these communities was sleep position, followed by issues related to bedding, co-sleeping, and soft bed surfaces. Additionally, caregivers in these communities often shared advice contradicting the guidelines set forth by the AAP. For instance, they advocated for the use of sleep positioning products and pillows with concave designs to cradle the head. They also recommended that infants sleep in separate rooms from adults to achieve
tong-jam, Korean slang for a long and deep sleep [
19].
(4) Field observations
The field observations included attending a baby fair and conducting home visits. At the baby fair, Korean parenting behaviors and sleep environments were examined through various baby products such as bedding, clothing, beds, strollers, and car seats. These observations were supplemented by promotional brochures and explanations from salespersons, and were recorded through non-participant observation using field notes and photographs to ensure objectivity and reproducibility. We also conducted the home visits where infants aged 3 and 4 months were raised and directly observed the sleep environments for infant and family of two households.
(5) Systematic classification of content
The educational content was selected through discussions with experts, considering the topic’s relevance and its cultural appropriateness for Korean audiences. The finalized educational content included: (1) sleep location; (2) sleep position; (3) bedding; (4) clothing and temperature; and (5) additional considerations such as the harmful effects of smoking, warnings against co-sleeping after consuming alcohol or taking sleeping pills, the use of pacifiers during sleep, breastfeeding, regular health checkups and vaccinations, avoiding sleep-related devices and items, and caution against indiscriminate information. These topics were subsequently incorporated into the main framework of PISS.
2) Structural formulation of the content as an educational protocol
The educational materials were made in the form of videos and booklets, based on the “Educational booklet of sleep-related sudden infant death investigation form” from a the National Forensic Services research project. The video production process included several stages: storyboarding, creating illustrations, writing narration scripts, designing, recording, and transcribing. The booklet was produced through content development, illustration creation, and design. The research team drew the illustrations to facilitate an intuitive understanding of the educational content and ensure accurate information.
3) Content validation
Content validity was confirmed by six health professionals: one Doctor of Philosophy (PhD) in pediatric nursing, two Master of Science in Nursing (MSN) in pediatric nursing, one MSN in community nursing, one MSN in adult nursing, and one MSN in nursing education. These professionals evaluated 11 items using a 3-point Likert scale (1=major revision; 2=minor revision; 3=no need for revision). The criteria assessed included accuracy, clarity, conciseness, professionalism, ease of understanding, readability, appropriateness of illustrations, structure and logic, volume, likelihood of achieving the intended purpose, and feasibility of the educational materials. In nursing, the method by Lynn [
23], which employs a 4-point Likert scale, is commonly used to assess content validity. However, due to the potential for dichotomous scoring, the 4-point scale must be used with caution [
24]. Therefore, this study developed and implemented a validity assessment framework using a 3-point Likert scale. The scores collected were calculated as the item-level content validity index (I-CVI) for item-specific validity and the scale-level content validity index (S-CVI) for overall validity. Traditionally, the I-CVI is calculated by determining the percentage of professionals who rated each item as 3 or 4 [
23]. However, in this study, we calculated the percentage of professionals who rated items as 3 on a 3-point Likert scale to ensure a more rigorous judgment. An I-CVI of .78 or higher, with 6–10 professionals, was considered to be in agreement based on the criteria by Lynn [
23]. The S-CVI was calculated as S-CVI/Ave (average of I-CVI) and S-CVI/UA (proportion of items rated 3 by all professionals). An S-CVI of .8 or higher was deemed concordant [
25].
After compiling feedback from six professionals on the content validity of the educational materials, the video analysis revealed that items with I-CVIs below .78 included the appropriateness of illustrations and volume, resulting in an S-CVI of .91 (
Table 1). In the booklet, items scoring below .78 in I-CVIs were ease of understanding, appropriateness of illustrations, and structure and logic, achieving an S-CVI of .82 (
Table 1). The S-CVI for both the video and the booklet was found to be acceptable; thus, the overall structure of the educational materials was retained. Enhancements were made by addressing the items with low I-CVI scores. For the video, adjustments were made to the amount of speech, pace, and duration, and enhancements such as background music and animation effects were incorporated. In the booklet, improvements included a concise description of the infants, a clearer linkage between topics, and the creation and strategic placement of additional illustrations.
RESULTS
The PISS is an intervention program designed with the Korean parenting styles and home environments in mind. Its primary objective is to help mothers of infants maintain a safe sleep environment and reduce the risk of sleep-related infant death. The program includes educational materials such as videos and booklets, as well as an educational kit. Follow-up support is provided through telephone reinforcement.
1) Educational materials
The video and booklet cover the following topics: sleep location, sleep position, bedding, clothing and temperature, and additional considerations. The video, which summarizes the booklet (
Table 2), incorporates a range of audiovisual elements such as illustrations, animation effects, narration, subtitles, and background music. The illustrations facilitate intuitive understanding by depicting safe sleeping environments—featuring firm and flat beds, separate and shared sleeping arrangements, and the supine sleep position—as well as unsafe environments, which include soft beds, the presence of objects, and the lateral sleep position. In total, 42 illustrations are featured in the video. To assist learners in recognizing the topic and tracking the progress of the education, the screen layout consistently displays the current topic, the title of the training, and a representative illustration of safe sleep on the left side of the screen. The latter part of the training material recaps the lessons learned and provides links to safe sleep organization websites to enhance learning further. The final video has a runtime of 12 minutes and 27 seconds (
Figure 1).
In contrast to the video, the booklet provides additional content and illustrations to enhance parents’ understanding of safe sleep practices. It begins with a brief introduction emphasizing the importance of safe sleep, followed by a table of contents. The main body of the booklet covers five essential topics on safe sleep, including the characteristics of infant sleep, precautions regarding the use of position maintenance products, and the Moro reflex (
Table 2). The booklet features 32 illustrations depicting both safe and unsafe sleep practices. While the illustration summarizing the key points is also included in the video, the booklet uniquely provides an illustrated quiz to reinforce safe sleep habits and a checklist for evaluating the sleep environment. The appendices contain a schedule for infant health checkups, standard immunization schedules, and a list of websites related to safe sleep. The booklet spans 25 pages and is depicted in
Figure 2.
Educational interventions have been designed to deliver content via videos and booklets, and to reinforce learning through educational kits and phone calls. Each educational kit includes an illustrated safe sleep sticker and a calendar-style activity diary (
Figure 3). The sticker, which is placed in the infant’s sleeping area, encourages family members to collectively practice safe sleep. The activity diary serves as a tool to monitor learning within the intervention group. Telephone reinforcement involves summarizing educational content, assessing participant’ understanding, and providing feedback on the home sleep environment.
DISCUSSION
Infant safe sleep is a key health behavior that caregivers can adopt to reduce the risk of sleep-related infant death. Its effectiveness has been well-documented by numerous studies and national public education programs in developed countries [
20]. In contrast, in Korea, a program centered on the Korean Centers for Disease Control and Prevention was launched in 2007, but it was not sustained for a long period of time [
12]. Furthermore, education in the fields of childcare has not sufficiently addressed cultural phenomena related to safe sleep in Korea [
26].
This study developed PISS, tailored to the Korean sociocultural context. This context was derived from various sources including related literature, institutional manuals, and insights gathered from online communities and field observations of households and baby fair. The sociocultural characteristics identified in Korea include bedding practices related to floor sleeping, a preference for warm environments influenced by cultural beliefs regarding the yin-yang principle, the prevalence of
tong-jam (Korean slang for a long and deep sleep), a preference for sleeping in separate rooms, the use of soft bedding and sleep positioning products, and the dissemination of inaccurate knowledge through online communities. We systematically organized these findings into categories such as sleep location, sleep position, bedding, clothing and temperature, along with additional considerations. Previous research on culturally specific safe sleep interventions has demonstrated their effectiveness in increasing adherence to safe sleep guidelines and reducing bedding-related suffocation risks [
27]. The PISS intervention developed through this study is expected to be highly relevant to Korean child care settings, which should increase parental adherence to safe sleep practices and ultimately improve sleep environments.
Another strength of PISS is its multifaceted design. The intervention includes a video and booklet that feature a quiz, a sleep environment checklist, a national health check-up schedule for infants and toddlers, a standard vaccination schedule, and additional resources about safe sleep. These components are designed to facilitate self-repetition and allow caregivers to practically and independently assess their infant’s sleep environment [
28]. Additionally, because safe sleep is a health behavior that benefits from long-term habituation, both the educational kit and telephone reinforcement are tailored to support the development of this habit. Multifaceted education has been shown to enhance learners’ attitudes and their willingness to adopt health behaviors [
29]. Since infants’ sleep environments are managed by various groups, including primary caregivers like parents and grandparents, postpartum doulas, and daycare personnel, PISS is expected to effectively increase their willingness to engage in safe sleep practices.
Finally, the safe sleep illustrations included in PISS are designed to enhance learners’ understanding of the content. In health education, visuals like illustrations are effective in overcoming language barriers and delivering medical information both comprehensively and accurately [
30]. The illustrations in PISS depict examples of both safe and unsafe sleeping environments. Safe environments are shown as firm, flat sleep areas, with options for sleeping separately or together, and the supine sleep position. Conversely, unsafe environments are portrayed with soft sleep areas, side sleeping positions, and soft sleep items. A representative, easy-to-understand illustration of infant safe sleep is featured at the end of the educational material. This approach is expected to not only improve the accuracy of information delivery during the intervention but also enhance the intuitiveness of the educational content, ultimately leading to increased educational utilization.
This study is significant because it incorporates Korean sociocultural characteristics into infant safe sleep education and develops a multifaceted, self-replicable intervention that includes a video, booklet, telephone counseling, and an educational kit. The intervention highlights the practical role of child health nurses as educators who can promote safe infant sleep practices in diverse community and clinical settings, including nurseries, postpartum care centers, maternal health education classes at public health centers, and visiting nursing services. Although the intervention showed potential, further study is needed to determine the optimal timing, intensity, and effect size, as well as parents’ comprehension of and satisfaction with the materials. Additionally, educational content derived from online communities and field observations at a baby fair and two households may be biased due to overrepresentation of specific parental viewpoints.
CONCLUSION
The significance of this study lies in our systematic review of safe sleep education content and Korean socio-cultural characteristics. This review was conducted through an analysis of the literature, institutional materials, online community discussions, and field observations. Based on these findings, we developed the PISS. The PISS will be beneficial not only to parents of infants but also to daycare personnel and medical staff, providing them with practical and specific information on safe sleep.
ARTICLE INFORMATION
Supplementary material
Figure 1.Video about Korean infant safe sleep practices. (A) Introduction. (B) Sleep location. (C) Sleep position. (D) Bedding. (E) Clothing and temperature. (F) Additional considerations. (G) Summary. (H) Additional information sources about safe sleep.
Figure 2.Booklet about Korean infant safe sleep practices. (A) Introduction. (B) Sleep location. (C) Sleep position. (D) Bedding. (E) Clothing and temperature. (F) Additional considerations. (G) Picture quiz. (H) Safe sleep checklist. (I) Appendix.
Figure 3.Booklet and activity kit.
Table 1.Professional content validity of educational materials about Korean infant safe sleep practices
|
Educational materials |
Item |
Professional 1 |
Professional 2 |
Professional 3 |
Professional 4 |
Professional 5 |
Professional 6 |
Instances of agreement |
I-CVIa)
|
|
Video |
Accuracy |
3 |
3 |
3 |
3 |
3 |
3 |
6 |
1.00 |
|
Clarity |
3 |
3 |
3 |
3 |
3 |
3 |
6 |
1.00 |
|
Conciseness |
3 |
3 |
3 |
3 |
3 |
3 |
6 |
1.00 |
|
Professionalism |
3 |
2 |
3 |
3 |
3 |
3 |
5 |
0.83 |
|
Ease of understanding |
3 |
3 |
3 |
3 |
2 |
3 |
5 |
0.83 |
|
Readability: font style, size |
3 |
3 |
3 |
3 |
3 |
3 |
6 |
1.00 |
|
Appropriateness of illustrations |
3 |
2 |
3 |
2 |
3 |
3 |
4 |
0.67 |
|
Structure and logic |
3 |
3 |
3 |
3 |
3 |
3 |
6 |
1.00 |
|
Volume |
3 |
3 |
3 |
2 |
2 |
3 |
4 |
0.67 |
|
Likelihood of achieving the intended purpose |
3 |
3 |
3 |
3 |
3 |
3 |
6 |
1.00 |
|
Feasibility |
3 |
3 |
3 |
3 |
3 |
3 |
6 |
1.00 |
|
Instances of universal agreement |
11 |
9 |
11 |
9 |
9 |
11 |
|
|
|
Proportion of agreement |
1.00 |
0.82 |
1.00 |
0.82 |
0.82 |
1.00 |
|
|
|
S-CVI/Aveb)
|
|
|
|
|
|
|
|
0.91 |
|
S-CVI/UAc)
|
|
|
|
|
|
|
|
0.64 |
|
Ave-proportion of agreement across expertsd)
|
|
|
|
|
|
|
|
0.91 |
|
Booklet |
Accuracy |
3 |
3 |
3 |
3 |
3 |
3 |
6 |
1.00 |
|
Clarity |
3 |
3 |
2 |
3 |
3 |
3 |
5 |
0.83 |
|
Conciseness |
3 |
3 |
3 |
3 |
3 |
3 |
6 |
1.00 |
|
Professionalism |
3 |
3 |
3 |
3 |
3 |
3 |
6 |
1.00 |
|
Ease of understanding |
3 |
3 |
2 |
3 |
2 |
3 |
4 |
0.67 |
|
Readability: font style, size |
2 |
3 |
3 |
3 |
3 |
3 |
5 |
0.83 |
|
Appropriateness of illustrations |
3 |
3 |
2 |
3 |
2 |
2 |
3 |
0.50 |
|
Structure and logic |
3 |
2 |
2 |
3 |
3 |
2 |
3 |
0.50 |
|
Volume |
3 |
2 |
3 |
3 |
3 |
3 |
5 |
0.83 |
|
Likelihood of achieving the intended purpose |
3 |
2 |
3 |
3 |
3 |
3 |
5 |
0.83 |
|
Feasibility |
3 |
3 |
3 |
3 |
3 |
3 |
6 |
1.00 |
|
Instances of universal agreement |
10 |
8 |
7 |
11 |
9 |
9 |
|
|
|
Proportion of agreement |
0.91 |
0.73 |
0.64 |
1.00 |
0.82 |
0.82 |
|
|
|
S-CVI/Aveb)
|
|
|
|
|
|
|
|
0.82 |
|
S-CVI/UAc)
|
|
|
|
|
|
|
|
0.36 |
|
Ave-proportion of agreement across expertsd)
|
|
|
|
|
|
|
|
0.82 |
Table 2.Content of the educational intervention for infant safe sleep practices in Korea
|
Subjects/contents |
Video |
Booklet |
Volume (video, booklet) |
|
Introduction |
|
|
29 sec, 5 pages |
|
Introduction of educational purpose |
○ |
○ |
|
|
Section 1. Sleep location |
|
|
2 min 26 sec, 3 pages |
|
Firm and flat sleep area |
○ |
○ |
|
|
Sleeping separately and together |
○ |
○ |
|
|
Characteristic of infant sleep |
- |
○ |
|
|
Section 2. Sleep position |
|
|
1 min 35 sec, 3 pages |
|
Supine sleep position |
○ |
○ |
|
|
Tummy time |
○ |
○ |
|
|
Cautions for use of position maintenance products |
- |
○ |
|
|
Section 3. Bedding |
|
|
1 min 38 sec, 3 pages |
|
Remove sleep items from the sleep area |
○ |
○ |
|
|
Swaddling |
○ |
○ |
|
|
Moro reflex |
- |
○ |
|
|
Section 4. Clothing and temperature |
|
|
46 sec, 1 page |
|
Sleep clothes |
○ |
○ |
|
|
Avoid overheating and maintain proper room temperature |
○ |
○ |
|
|
Section 5. Additional considerations |
|
|
4 min 17 sec, 4 pages |
|
Harmful effects of smoking |
○ |
○ |
|
|
Risk of sharing bedding after drinking |
○ |
○ |
|
|
Risk of sharing bedding after taking sleeping pills |
○ |
○ |
|
|
Positive aspects of pacifier use during sleep |
○ |
○ |
|
|
Positive aspects of breastfeeding |
○ |
○ |
|
|
Regular health check-ups and vaccinations |
○ |
○ |
|
|
Avoid using sleep-related devices and items |
○ |
○ |
|
|
Beware of indiscriminate information |
○ |
○ |
|
|
Wrap-up |
|
|
1 min 16 sec, 6 pages |
|
Summary of contents |
○ |
○ |
|
|
Sleep environment check: quiz, checklist |
- |
○ |
|
|
National health checkup schedule for infant and toddler |
- |
○ |
|
|
Standard vaccination schedule |
- |
○ |
|
|
Additional information resource about safe sleep |
○ |
○ |
|
|
Total length |
|
|
12 min 27 sec, 25 pages |
REFERENCES
- 1. Centers for Disease Control and Prevention (CDC). Sudden unexpected infant death and sudden infant death syndrome: SUID investigation training resources [Internet]. CDC; 2018 [cited 2025 Sep 6]. Available from: https://www.cdc.gov/sudden-infant-death/php/training/
- 2. Moon RY, Carlin RF, Hand I. Evidence base for 2022 updated recommendations for a safe infant sleeping environment to reduce the risk of sleep-related infant deaths. Pediatrics. 2022;150(1):e2022057991. https://doi.org/10.1542/peds.2022-057991
- 3. Moon RY, Hauck FR. Risk factors and theories. In: Duncan JR, Byard RW, editors. SIDS sudden infant and early childhood death: the past, the present and the future. University of Adelaide Press; 2018. p. 169-186.
- 4. Sidebotham P, Bates F, Ellis C, Lyus L. Preventive strategies for sudden infant death syndrome In: Duncan JR, Byard RW, editors. SIDS sudden infant and early childhood death: the past, the present and the future. University of Adelaide Press; 2018. p. 217-256.
- 5. Ahn YM, Yang KM, Ha HI, Cho JA. Risk factors for sudden infant death syndrome and sleeping practices in Korea. Child Health Nurs Res. 2020;26(1):82-89. https://doi.org/10.4094/chnr.2020.26.1.82
- 6. Kim JB. ONDOL as a Korean ancient’s greatest wisdom improves our immunity by keeping head cool and feet warm. Int J Ondol. 2017;2017(1):1-4.
- 7. Lee CY. Understanding the yin-yang doctrine of Korean Medicine as a metaphor. J Physiol Pathol Korean Med [Internet]. 2014 [cited 2025 Sep 6];28(5):465-477. Available from: https://www.kci.go.kr/kciportal/ci/sereArticleSearch/ciSereArtiView.kci?sereArticleSearchBean.artiId=ART001923248
- 8. Nomura M. A study on the continuance and variation of Korean traditional postnatal care in a modern postpartum care center. J Korean Folk Soc. 2016;63:37-77. https://doi.org/10.21318/TKF.2016.05.63.37
- 9. Dennis CL, Fung K, Grigoriadis S, Robinson GE, Romans S, Ross L. Traditional postpartum practices and rituals: a qualitative systematic review. Womens Health (Lond). 2007;3(4):487-502. https://doi.org/10.2217/17455057.3.4.487
- 10. Chung S, An H. Cultural issues of co-sleeping in Korea. Sleep Med Res. 2014;5(2):37-42. https://doi.org/10.17241/smr.2014.5.2.37
- 11. Alexeyeff K. Sleeping safe: perceptions of risk and value in Western and Pacific infant co-sleeping In: Glaskin K, Chenhall R, editors. Sleep around the world. culture, mind, and society. Palgrave Macmillan; 2013. p. 113-132. https://doi.org/10.1057/9781137315731_7
- 12. Korea Disease Control and Prevention Agency (KDCA). 2007 Sudden infant death syndrome prevention leaflet [Internet]. KDCA; 2013 [cited 2025 Sep 6]. Available from: https://www.kdca.go.kr/gallery.es?mid=a20503020000&bid=0003&act=view&list_no=136954
- 13. Statistics Korea. Causes of death statistics in 2023 [Internet]. Statistics Korea; 2025 [cited 2025 Sep 6]. Available from: https://kosis.kr/statHtml/statHtml.do?orgId=101&tblId=DT_1B34E07&vw_cd=MT_ZTITLE&list_id=F_27&seqNo=&lang_mode=ko&language=kor&obj_var_id=&itm_id=&conn_path=MT_ZTITLE
- 14. Mery JN, Vladescu JC, Sidener TM, Reeve KF, Day-Watkins J. Safe to sleep: a systematic review of the safe infant sleep training literature across relevant personnel. J Neonatal Nurs. 2021;27(6):381-395. https://doi.org/10.1016/j.jnn.2021.06.001
- 15. Jang S, Kim IO. Development of an infants’ sleep health program using a video for SIDS prevention education and measurement of the program’s effects. Child Health Nurs Res. 2015;21(1):11-19. https://doi.org/10.4094/chnr.2015.21.1.11
- 16. Cho JA, Sohn M, Lee S, Ahn YM. Knowledge on sudden unexplained infant death-related safe sleep practices and infant cardiopulmonary resuscitation in pediatric nurses. Child Health Nurs Res. 2020;26(4):454-462. https://doi.org/10.4094/chnr.2020.26.4.454
- 17. Ahn YM, Cho JA. Survey of Korean daycare personnel on safe sleep practices related to sudden unexplained infant death: a cross-sectional exploratory study. Child Health Nurs Res. 2022;28(4):299-309. https://doi.org/10.4094/chnr.2022.28.4.299
- 18. Duncan E, O’Cathain A, Rousseau N, Croot L, Sworn K, Turner KM, et al. Guidance for reporting intervention development studies in health research (GUIDED): an evidence-based consensus study. BMJ Open. 2020;10(4):e033516. https://doi.org/10.1136/bmjopen-2019-033516
- 19. Ahn YM, Cho JA, National Forensic Service Republic of Korea (NFS). Study of risk factors and development of initial assessment tool of sudden unexplained infant death (SUID) based on child rearing practices (CRP) [Internet]. NFS; 2021 [cited 2025 Sep 6]. Report No.: TRKO202200007878. Available from: https://www.ntis.go.kr/outcomes/popup/srchTotlRschRpt.do?cmd=get_contents&rstId=REP-2022-01112391836
- 20. Duncan JR, Byard RW, editors. SIDS sudden infant and early childhood death: the past, the present and the future. University of Adelaide Press; 2018.
- 21. Cohen MC, Scheimberg IB, Beckwith JB, Hauck FR, editors. Investigation of sudden infant death syndrome. Cambridge University Press; 2019.
- 22. Ahn YM, Yang KM, Ha HI, Cho JA. Cultural variation in factors associated with sudden infant death during sleep. BMC Pediatr. 2021;21(1):443. https://doi.org/10.1186/s12887-021-02894-8
- 23. Lynn MR. Determination and quantification of content validity. Nurs Res. 1986;35(6):382-385.
- 24. Almanasreh E, Moles R, Chen TF. Evaluation of methods used for estimating content validity. Res Social Adm Pharm. 2019;15(2):214-221. https://doi.org/10.1016/j.sapharm.2018.03.066
- 25. Polit DF, Beck CT. The content validity index: are you sure you know what’s being reported?: critique and recommendations. Res Nurs Health. 2006;29(5):489-497. https://doi.org/10.1002/nur.20147
- 26. Childcare Center Safety and Insurance Association. Sudden infant death syndrome prevention video [Internet]. Childcare Center Safety and Insurance Association; 2011 [cited 2025 Dec 9]. Available from: https://e.csia.or.kr/user/bbs/recsInstrctrView.do?idx=585
- 27. Baddock SA, Tipene-Leach D, Williams SM, Tangiora A, Jones R, Iosua E, et al. Wahakura versus Bassinet for safe infant sleep: a randomized trial. Pediatrics. 2017;139(2):e20160162. https://doi.org/10.1542/peds.2016-0162
- 28. Khalil A, Amin E, Alrafay SSE, Khalifa OA. The effects of a self-learning package on mothers’ knowledge and practices towards caring for their children with phenylketonuria. J Med Life. 2023;16(2):215-219. https://doi.org/10.25122/jml-2022-0258
- 29. Berkley-Patton J, Bowe Thompson C, Goggin K, Catley D, Berman M, Bradley-Ewing A, et al. A religiously-tailored, multilevel intervention in African American churches to increase HIV testing: rationale and design of the taking it to the pews cluster randomized trial. Contemp Clin Trials. 2019;86:105848. https://doi.org/10.1016/j.cct.2019.105848
- 30. Haragi M, Ishikawa H, Kiuchi T. Investigation of suitable illustrations in medical care. J Vis Commun Med. 2019;42(4):158-168. https://doi.org/10.1080/17453054.2019.1633237
