We intended to include representative videos about cesarean delivery that the public could access. The Google keyword search tool Google AdWords [11], a method used by Williams et al [12], was used to identify appropriate search terms that the public would use to explore the term “cesarean section” on YouTube. From the original keyword cesarean section, a list of popular terms, such as 38 weeks c section, second c section, 3 months after c section, first c section, repeat c section, and c section complications, was retrieved. Each term was queried by combining 3 terms, namely, c section, cesarean section, and cesarean delivery, and a total of 18 terms were queried. A YouTube search was conducted on April 2, 2021. As the goal of the search was to identify the videos that the public were watching most frequently, the videos were sorted by view count using the YouTube advanced search options. The criteria for including the videos were as follows: (1) English language used, (2) primary content related to cesarean delivery, and (3) acceptable audiovisual quality. The exclusion criteria were as follows: (1) languages other than English, (2) poor audio or visual clarity, (3) animal videos, and (4) duplicate videos.

For the search terms, the top 300 initial videos were included for review, as determined by the Relevance filter according to YouTube’s algorithm. A total of 52 videos were excluded (14 animal videos, 30 non–English-language videos, 5 videos with poor audio or visual clarity, and 3 duplicate videos). A list of the top 100 videos was populated based on view count, and this list served as the basis for the subsequent analysis. A description of the search strategies is presented in Figure 1.

For each video, we collected the objective (video title, number of views, uploaded day, uploader’s name, length of the video, days since upload, total number of “likes” and “dislikes” as depicted by the “thumbs up” and “thumbs down” icons, details and sources related to the cesarean delivery included in the video) and subjective data (the purpose and type of content).

Based on the content in the videos, the videos were categorized into five groups: (1) explanations of surgery (providing general cesarean delivery–related information), (2) surgery procedure (showing or explaining detailed surgical procedure techniques and processes), (3) personal experiences (sharing personal experiences and feelings related to pregnancy and delivery), (4) postpartum care (providing information on postsurgical care, eg, nutrition, exercise, and wound care), and (5) others (mock practice videos in various circumstances, appreciation of medical dramas related to cesarean delivery, and description of surgical instruments). We classified videos that include explanations of surgery and surgical procedures as videos directly related to cesarean delivery, and videos that included personal experiences or postpartum care were classified as videos indirectly related to cesarean delivery (Table 1).

Based on their authorship, the videos were classified into five basic groups: (1) academics (authors were affiliated with a university), (2) physicians (authors were not affiliated with a university but were physicians), (3) patients (a woman who had already delivered or was currently pregnant, or her husband), (4) commercial establishments (attention to a product or service), and (5) paramedical (allied health therapist, physiotherapist, or dietitian). We further categorized the videos uploaded by academic and physician groups into the medical group, and those uploaded by patients, commercial establishments, and paramedical groups were categorized into the nonmedical group (Table 1).

Because there are no established standards for evaluating video quality, we prepared an arbitrary scoring system by referring to a previous study [13-15]. The evaluation factors were divided into the part that evaluates the general quality of the video, whether important information on cesarean delivery was included and explained, and how much scientific evidence was specified (Textbox 1). For general video quality and flow of video contents, each parameter was scored on a scale of 1 to 3. The information on cesarean delivery was divided into 5 elements and scored as follows depending on the degree of explanation: 0 points, not mentioned; 1 point, mentioned briefly; 2 points, mentioned in detail. For videos based on scientific evidence, there were two subdivided items: 0 points were given if there was no mention, and 1 point was given. Thus, the total score of the 5 items ranged from a minimum of 2 to a maximum of 18 points. Three professional obstetricians (two professors at the University Hospital of Obstetrics and one obstetrician fellow) independently evaluated the quality of each video, and the score used for the analysis was the average of the 3 scores.

To assess the popularity of the videos, we used the like ratio (like × 100/[like + dislike]), view ratio (number of views/days), and video power index (VPI) (like ratio × view ratio/100).

Data are shown as median (range) for continuous variables and as n (%) for categorical variables. Comparisons were made between videos directly related to cesarean delivery and videos with indirectly related contents and between the medical and nonmedical groups using the Mann-Whitney U test. Comparisons of the difference in uploaded contents between medical and nonmedical groups were analyzed by the Fisher exact test. The Kruskal-Wallis test with Bonferroni corrections was used to compare scores according to the contents of the uploaded videos. Statistical analysis was conducted using SPSS software, version 27.0 (IBM Corporation). Statistical significance was set at P<.05. The reliability between the YouTube videos and the scores by the three obstetricians on the criteria for the items was assessed using intraclass correlation coefficients.

Institutional review board approval was waived for this study because only publicly available data were used.

Our study identified that the most viewed video about cesarean delivery was a video that was uploaded in 2008 by Nucleus Medical Media, which is a company that specializes in producing medical illustrations and animations. This video is a well-organized video containing overall information on cesarean delivery, such as operation indication, pelvic anatomy expressed by animations, and detailed step-by-step explanations of surgical procedures, preoperative preparation, and postoperative and postpartum management. This video also received the most likes and the highest score, and it also showed the fifth highest VPI. This video was uploaded in 2008, which is relatively early on YouTube, but it was still considered the best organized and most informative video about cesarean delivery. Of the videos included in this study, 41 videos were uploaded up by the end of 2015, and 59 videos had been uploaded since 2015. Our results showed that videos that were directly related to cesarean delivery were often uploaded at earlier dates, and the proportion of videos that were directly related to cesarean delivery out of all videos after 2015 decreased compared to that of videos uploaded by the end of 2015. In addition, although the difference was statistically insignificant, more than half of the videos from the medical group were uploaded by the end of 2015, while more videos were uploaded by the nonmedical group after 2015 (21/41, 51%, vs 21/59, 36%; P=.12). These results suggest that as YouTube becomes more popular and laypeople can easily access and produce content, the number of videos containing contents such as personal experiences and postpartum care being uploaded by laypeople is greater than the number of professional videos containing medical information on cesarean delivery being uploaded by medical groups. However, the videos uploaded after 2015 were more popular, as indicated by their VPIs and like ratios, and they also received more comments than the videos uploaded by the end of 2015. These results suggest that the quality and reliability of information provided by YouTube is not related to popularity. Also noteworthy is that although videos directly related to cesarean delivery had higher quality scores, their like ratios were notably lower than those of videos indirectly related to cesarean delivery; moreover, videos uploaded by medical groups scored higher, but their like ratios tended to be lower. The VPI, which is a comprehensive indicator reflecting popularity, did not show any differences between videos directly related to cesarean delivery and videos indirectly related to cesarean delivery or between videos uploaded by medical and nonmedical groups. These results showed that laypeople expressed their preferences regardless of the quality of the video. These results are similar to those of previous studies. Staunton et al [16] reviewed 50 videos regarding scoliosis and found that videos with greater educational quality were associated with a lower number of views. Ferhatoglu et al [17] recently reported an association between high VPI scores and low Sleeve Gastrectomy Scoring System scores in their review of sleeve gastrectomy videos on YouTube.

In addition, the results of this study showed that although the total possible score for each video was 18 points, the median score was 6 (range 1-16), which is relatively low. Among the videos, only 13 scored more than 10 points, and the remaining videos showed relatively low scores. The reason for this finding is that most of the videos received low scores in the evaluation items for the information elements related to cesarean delivery (median score 2, range 0-9). Moreover, there were few videos containing the indications for cesarean delivery and maternal or fetal complications that may occur after surgery (n=23 and n=21, respectively), which is important information to be aware of before undergoing a cesarean delivery. In addition, the majority of the videos (80/100, 80%) had a score of 0 in the scientific evidence category, showing that insufficient references were provided for the information in the video. It may not be appropriate to use the scoring method used in this study to evaluate the quality of videos on YouTube, where people can freely produce and upload videos on topics of interest. However, our results showed that videos on YouTube have limitations in providing general and well-organized scientific knowledge of cesarean delivery. It is possible that this limitation is the reason that while the number of searches for “cesarean section” on YouTube has been decreasing over time, the number of YouTube users and searches for “cesarean section” on the Google website has been increasing (Figure 2 and Figure 3). Although YouTube can be seen as a potentially useful medium to search for cesarean delivery–related knowledge and increase awareness, the user must be aware that the information uploaded is not regulated and the quality of the content thus needs to be validated.

This study had some limitations. First, although the assessment method used in this study was adapted from the DISCERN criteria [15], and it reflects the opinions of experts on cesarean delivery, the necessary information for cesarean delivery was included in the evaluation items; however, this method was created arbitrarily by us. Thus, more verification is needed to ensure that the assessment method is suitable for accurately evaluating the quality of videos on cesarean delivery. Second, we only analyzed videos that were in English; thus, sampling bias could have occurred. It is necessary to evaluate videos in other languages for a more comprehensive analysis of the features in videos on cesarean delivery.

This study is the first to analyze YouTube videos on cesarean delivery, and it contributes to a better understanding of the available information on cesarean delivery that is widely viewed on YouTube. Our results showed that the videos directly related to cesarean delivery, such as explanations of the surgery and actual surgical procedures, were mainly uploaded by medical groups and scored higher than the videos indirectly related to cesarean delivery, which were mainly uploaded by nonmedical groups. In addition, videos directly related to cesarean delivery were more often uploaded earlier in time, and the proportion of videos that were directly related to cesarean delivery decreased after 2015. In our results, when we used the scoring method to evaluate the accuracy of the important information on cesarean delivery, a majority of videos had low scores, showing that YouTube has limitations in delivering accurate information on cesarean delivery.