Publication had relevant information on specific barriers to implementation listed in the abstract; 2) the study was published in a peer-reviewed journal; 3) the study included data on the sample population, sample size, and location of implementation; 4) the study was original research; and 5) the study was published in English. Studies testing the efficacy of KMC or STS practice (e.g. randomized controlled trials) were included if issues of acceptability, feasibility, or barriers to practice for parents or practitioners were documented in the abstract. Any publication published before August 13, 2013 (the date of the final database search) was eligible for inclusion. We excluded literature reviews, conference proceedings, letters to the editor, and abstracts in order to prevent double counting of data and to ensure that all barriers were understood in the context of the entire study. We searched nine VercirnonMedChemExpress CCX282-B electronic databases: PubMed, EMBASE, Scopus, Web of Science, and the WHO Regional Databases (AIM, LILACS, IMEMR, IMSEAR, and WPRIM). We searched all databases using the following search terms: “Kangaroo Mother Care” OR “Kangaroo Care” OR “Skin to skin care”. In addition, because at least one relevant article identified from a list of references in a literature review included the terms Kangaroo Mother Care in quotations and the term Skin to skin, we also searched PubMed for “‘Kangaroo Mother Care'” and “Skin to skin”. We used broad search criteria to ensure that relevant articles were not missed, and we then filtered and excluded many articles based on the eligibility criteria mentioned above. Reference lists from literature reviews identified in the database search were also scanned for relevant titles, and articles were also identified in consultation with the DactinomycinMedChemExpress Dactinomycin authors on this study. Recommendations for studies to be included in the review were also received from participants at the KMC Acceleration Meeting in Istanbul, October 2013[24] and in consultation with leaders in the fields of KMC and newborn health.PLOS ONE | DOI:10.1371/journal.pone.0125643 May 20,3 /Barriers and Enablers of KMCData collectionAfter our initial database search and identification of additional studies through recommendations and scans of reference lists, study titles and abstracts were screened by two reviewers (GS and EK) for inclusion. In situations when a study’s eligibility was disputed, a third reviewer (SU) provided an independent assessment until consensus was reached. 96 articles were reviewed to identify a comprehensive list of barriers to KMC practice in advance of the KMC Acceleration Convening [24]. A data extraction sheet was piloted and tested using these 96 articles. This piloting allowed for preliminary identification of relevant barriers and enablers to be included in the final review as well as final determination of stakeholders to be included in the review: mothers, fathers, community health workers, nurses, physicians, and program managers. The final tool included fields for collecting publication details, relevant study characteristics (sample size, location, and a short description of each study), barriers for each stakeholder group, and enablers to practice for mothers. Results from the preliminary analysis were shared at the KMC Acceleration Convening, ensuring that key stakeholders in the KMC community generally supported the methodology (described in further detail in the next section) and found the preliminary results to be consisten.Publication had relevant information on specific barriers to implementation listed in the abstract; 2) the study was published in a peer-reviewed journal; 3) the study included data on the sample population, sample size, and location of implementation; 4) the study was original research; and 5) the study was published in English. Studies testing the efficacy of KMC or STS practice (e.g. randomized controlled trials) were included if issues of acceptability, feasibility, or barriers to practice for parents or practitioners were documented in the abstract. Any publication published before August 13, 2013 (the date of the final database search) was eligible for inclusion. We excluded literature reviews, conference proceedings, letters to the editor, and abstracts in order to prevent double counting of data and to ensure that all barriers were understood in the context of the entire study. We searched nine electronic databases: PubMed, EMBASE, Scopus, Web of Science, and the WHO Regional Databases (AIM, LILACS, IMEMR, IMSEAR, and WPRIM). We searched all databases using the following search terms: “Kangaroo Mother Care” OR “Kangaroo Care” OR “Skin to skin care”. In addition, because at least one relevant article identified from a list of references in a literature review included the terms Kangaroo Mother Care in quotations and the term Skin to skin, we also searched PubMed for “‘Kangaroo Mother Care'” and “Skin to skin”. We used broad search criteria to ensure that relevant articles were not missed, and we then filtered and excluded many articles based on the eligibility criteria mentioned above. Reference lists from literature reviews identified in the database search were also scanned for relevant titles, and articles were also identified in consultation with the authors on this study. Recommendations for studies to be included in the review were also received from participants at the KMC Acceleration Meeting in Istanbul, October 2013[24] and in consultation with leaders in the fields of KMC and newborn health.PLOS ONE | DOI:10.1371/journal.pone.0125643 May 20,3 /Barriers and Enablers of KMCData collectionAfter our initial database search and identification of additional studies through recommendations and scans of reference lists, study titles and abstracts were screened by two reviewers (GS and EK) for inclusion. In situations when a study’s eligibility was disputed, a third reviewer (SU) provided an independent assessment until consensus was reached. 96 articles were reviewed to identify a comprehensive list of barriers to KMC practice in advance of the KMC Acceleration Convening [24]. A data extraction sheet was piloted and tested using these 96 articles. This piloting allowed for preliminary identification of relevant barriers and enablers to be included in the final review as well as final determination of stakeholders to be included in the review: mothers, fathers, community health workers, nurses, physicians, and program managers. The final tool included fields for collecting publication details, relevant study characteristics (sample size, location, and a short description of each study), barriers for each stakeholder group, and enablers to practice for mothers. Results from the preliminary analysis were shared at the KMC Acceleration Convening, ensuring that key stakeholders in the KMC community generally supported the methodology (described in further detail in the next section) and found the preliminary results to be consisten.