Assessment of the Quality of Information of YouTube Videos Regarding Cervical Disc Replacement
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* Tanushk Luke Brito Martyn
* Joseph Frederick Baker

## Abstract

**Background** Patients have been shown to use YouTube as a source of information regarding medical procedures. There is currently limited information regarding the quality and educational content of information regarding cervical disc replacement (CDR). The purpose of this study was to determine the quality and educational content of YouTube videos on CDR using a procedure-specific scoring system.

**Methods** A search was performed on YouTube using the phrase “cervical disc replacement.” The first 50 videos were included in this study. Video data were collected, including the title, duration, provider type, number of views, days since upload, number of comments, and the number of likes and dislikes. The videos were also assessed using the *JAMA* and Global Quality Score criteria for video quality and educational content, as well as a cervical disc replacement-specific score (CDRSS) was devised for this study.

**Results** The average number of views was 73785.2. The average video duration was 5.9 minutes. Overall, video quality and educational content were low. The largest proportion of videos was classified as “surgeon professional” at 32%. The average CDRSS was 4.7. None of the quality measure scores recorded correlated with video variables.

**Conclusion** Videos concerning CDR were available for review on YouTube. The educational quality and reliability of these videos were low.

**Clinical Relevance** We suggest that other sources of information be utilized by patients and surgeons as an adjunct for education and informed consent regarding CDR.

**Level of Evidence** 6.

*   cervical disc replacement
*   cervical spine
*   patient education as topic

## INTRODUCTION

As the breadth of content on the internet continues to expand and change the world we live in, so does its ability to act as a source of credible health information. As of January 2021, 59.5% of the global population used the internet on a regular basis.1 YouTube ([https://www.youtube.com/](https://www.youtube.com/)) is the second most popular social media platform2 with over 2 billion user visits per month. It is accessed in more than 100 countries around the world and viewed in 80 different languages. More than 500 hours of video are uploaded every minute3 with more than a billion hours of video viewed every day. The average viewer aged 18 years or older spends 41.9 minutes on YouTube daily.4 

There is a burgeoning library of health-related content on YouTube.5–17 The site is easily accessible to all potential patients and therefore may often be the first website visited if they are looking for information. It is thought that in the coming years, video-based information will be a primary source of data delivery, highlighting the growing importance for video quality accuracy.7,17 More patients now turn to the internet as their first source of health information.18 This has had the direct benefit of empowering the patient so they feel more involved in their health care and the decision-making associated with it. However, it must be remembered that in almost all cases, health information online will not go through the same stringent protocol as is required for academic papers. Of note, YouTube videos require no peer review (or any actual regulation) prior to upload.5,18 As patients aim to educate themselves about potential procedures, prior to visiting a health practitioner, it is important to analyze which videos are currently available to understand what information patients are receiving.

Degenerative diseases of the cervical spine may be addressed by a variety of procedures. This depends on a number of variables, including patient, surgeon, and disease-specific features. These well-known procedures, among others, include anterior cervical discectomy and fusion (ACDF) and cervical disc replacement (CDR).19 CDR is newer than ACDF, originating in the 1960s as a means of minimizing adjacent segmental disease, which is a well-recognized problem following fusion.20 Its clinical benefits over the “gold standard” ACDF continue to be explored. While early devices had higher complication rates and poorer results, technological advancements have led to a selection of implants with excellent midterm results.19 

CDR is extensively marketed on the internet, and anecdotally many patients will research their condition and present seeking CDR in preference to a fusion.21 Previous reports on the quality of YouTube-based health-related information have shown varying results. Therefore, our aim was to determine the quality and educational content of YouTube videos on CDR using a specific scoring system we devised for this study. Our hypothesis was that the quality and educational content of the videos would be low.

## METHODS

On 19 March 2021, YouTube’s search engine was queried with the keywords “cervical disc replacement.” The search was conducted at an independent internet cafe, so no biases associated with previous searches of the primary author could be associated with the study. The search was performed in Hamilton, New Zealand. Only videos in English were considered for this study. The first 50 videos based on this particular search were recorded. The decision to review only the first 50 videos was made because previous peer-reviewed articles that have analyzed orthopedic YouTube videos followed the same format.5,6,8,10,22 

Immediately after the initial search had been made, the following data were recorded: title, video duration, number of views, days since upload, view ratio (views divided by days since upload), number of comments, number of likes, number of dislikes, like ratio (likes × 100/like + dislike), and the Video Power Index (VPI). The VPI is a calculation determined from the formula like ratio × view ratio/100. This formula takes into account the number of times a video has been viewed and the total “likes” it has received, thus allowing a standardized method of determining its popularity.10 

The videos’ contents were analyzed using the CDR-specific score (CDRSS) we devised for this study (Table 1). It was based on the seminal paper by Mathur et al and their Scoliosis-Specific Score.23 Further orthopedic articles have followed in a similar style with their own modified versions to reflect their topic analysis.6,8,10,13,16,17,22 By following these examples, we modified and devised a score to highlight information we felt was important and beneficial for patients to comprehend about CDR prior to consenting for surgery. The key components of the informed consent process as outlined by Todd et al24 were considered when developing the CDRSS. It was split into 7 categories: (1) causes and presentation; (2) indications; (3) contraindications; (4) benefits; (5) complications; (6) treatment options; and (7) surgical techniques. Each category had a number of variables associated with it, and each variable was assigned 1 point. The maximum total score a video could receive was 40.

View this table:
[Table 1](http://ijssurgery.com//content/16/2/272/T1)

Table 1 
Cervical disc replacement-specific score (CDRSS).

The *JAMA* benchmark criteria were used to assess the accuracy and reliability of the videos in this study. *JAMA*’s benchmark criteria are a nonspecific and objective tool consisting of 4 individual criteria: authorship, attribution, currency, and disclosure. Online videos and resources can be analyzed via this benchmark to assess their accuracy and reliability. The reviewer assigns 1 point for each fulfilled criterion present. A score of 0 indicates a poor source accuracy and reliability; a score of 4 indicates high source accuracy and reliability (Table 2).25 While these criteria are not validated, they have been used in nearly all studies of this nature.5–8,10,12,13,16,17,22 

View this table:
[Table 2](http://ijssurgery.com//content/16/2/272/T2)

Table 2 
*JAMA* benchmark criteria.

General educational content (not specific to CDRSS) was assessed via the Global Quality Score (GQS). This is another nonvalidated tool that is commonly used to assess the content of online resources. It is summarized in Table 3.8,10 There are 5 potential grades to assign to a video. Score 1 is a video of poor quality; it is considered that a video with this score is unlikely to be of any use for patient education. Score 5 is a video of excellent quality and thought to be highly useful to patients.6,8,10,22 

View this table:
[Table 3](http://ijssurgery.com//content/16/2/272/T3)

Table 3 
The Global Quality Score criteria.

The type of video was stratified into 5 different categories: surgeon professional, academic, commercial, nonsurgeon professional, and unspecified. These determinants were made by the first author with any uncertain classifications clarified by the senior author. Surgeon-professional videos had a surgeon either showing how a CDR is inserted or talking about the process. Academic videos were panel-type or group-type discussions involving surgeons analyzing the available research regarding the CDR. Commercial videos were advertisements from a company regarding their specific CDR. Nonsurgeon-professional videos included any health professional, who was not a spinal surgeon, discussing the CDR. Unspecified videos included all videos that did not fit into the prior categories, including features such as patient testimonials regarding the CDR.

### Statistical Methods

All data were recorded and stored in an Excel spreadsheet. Results are reported as mean (±SD) and range as needed. Pearson correlation analyses were performed to determine significant association. One-way analysis of variance was used to compare subgroups. Statistical significance was accepted as *P* < 0.05.

## Results

The 50 videos included in this study are shown in Table 4. The mean number of views per video was 73785.2 ± 391662.7 (range 323–2,781,849). The mean video duration was 5.9 ± 5.9 minutes (range 1.1–29). Additional video characteristics are summarized in Table 5.

View this table:
[Table 4](http://ijssurgery.com//content/16/2/272/T4)

Table 4 
All 50 YouTube URLs (web addresses) included in this study.

View this table:
[Table 5](http://ijssurgery.com//content/16/2/272/T5)

Table 5 
Video characteristics of the YouTube videos included in this study.

Surgeon-professional videos made up the largest proportion for type of video at 32%. This was followed by commercial (28%), unspecified (20%), and academic (16%). Nonsurgeon-professional videos made the lowest proportion at 4%. The mean CDRSS score was 4.7 ± 3.6 (range of 0–20). The mean *JAMA* score was 1.1 ± 0.3 (range 1–2). The mean GQS score was 1.9 ± 0.7 (range 1–3). None of the quality measure scores recorded correlated with video variables. In particular, video views, run time, like ratio, VPI, or type of video had no statistical significance in regard to its quality measure score.

## DISCUSSION

The aim of this study was to determine the quality and educational content of YouTube videos on CDR. Our study showed that the first 50 videos available to a user who searches on YouTube with the keywords “cervical disc replacement” were of poor quality and educational content when assessed with the scoring tools CDRSS, *JAMA*, and GQS. Of particular importance, these videos could not be reliably used to supplement or be considered a useful adjunct to the process of informed consent.24 

Previous spine-related articles with a comparable method have arrived at similar conclusions. Brooks et al14 studied lumbar discectomy videos, Staunton et al22 studied scoliosis videos, and Ovenden et al5 studied ACDF videos, all on YouTube. All articles showed that their respective videos were of poor quality and educational content. This is a worrying trend. Patients reportedly see the internet, and video content specifically, as a primary source of information for their health education.7,17,18 The distinct lack of quality videos means that a large majority of patients will continue to be inadequately educated about their health concerns. This can have deleterious influence on the informed consent process. The greatest concern is that if assumptions are made that patients have been adequately educated by watching YouTube videos we sampled, the likelihood is that a large majority are not receiving the appropriate counseling prior to a CDR procedure. Additional patient education, face to face, is mandatory to correct any misconceptions gained from accessing information on YouTube.

The CDRSS was designed with patient education and informed consent as its primary aim. Todd et al24 detailed a specific checklist in their paper that spinal surgeons should aim to fulfill in order to adequately prepare a patient for routine elective surgery. In particular, informed consent should address the proposed procedure; the natural history of the condition if left untreated; the risks, benefits, and alternatives to surgery; and if there were any nonoperative treatments to surgery.24 Todd et al also documented spinal surgery cases where the operation was carried out to an appropriate standard, but the patient was successful in a claim against the surgeon/institution that the surgery occurred despite inadequate counseling/preparation. In one particular case, the patient was referred to a website that did not contain information that one of the risks of that particular spinal surgery was potential damage to the spinal cord. With this in mind, we aimed to make the CDRSS as comprehensive and patient- centric as possible when addressing all potential items that should be addressed for informed consent in CDR surgery. Our results are clear that information regarding CDR on YouTube can only poorly complement the informed consent process, if at all.

This poses issues for the spinal surgeon looking to use YouTube as an educational supplement or information adjunct for their patient prior to CDR surgery. Good quality, patient-centric videos that are produced with informed consent in mind were not apparent in our YouTube search. Only 1 video, entitled “Risks of surgery on the neck—ACDF and cervical disc replacement”26 specifically touched on complications. If surgeons wish to use YouTube for the aforementioned reasons, we recommend they search for and collect a set of CDR videos currently available that addresses as many of the 40 variables on the CDRSS. They could also create and upload their own video, which has the added benefit of reflecting their local culture and treatment trends.

The main limitation with our study was that only the first 50 videos were assessed. While it has been shown that most internet users do not go past the first 2 pages of a search result,27 our findings must still take into account that a specific well-made video might not have been viewed by us. Our search query was also only performed in the English language, and therefore videos about CDR in another language were not assessed. The findings of this study may have limited applicability beyond the English-speaking world.

Video quality was also only analyzed using CDRSS, *JAMA*, and GQS. These criteria often meant that patient-testimonial videos received low grades as they had no real clinical information. We acknowledge that the benefit a patient might receiving from hearing a testimonial from another patient is significant. There could be a place for videos like these in conjunction with videos of better information quality.

## CONCLUSION

Videos concerning CDR on YouTube were of poor educational quality and reliability. They cannot reliably complement the informed consent process. We recommend that other sources of information be utilized by patients and surgeons as an adjunct for education and informed consent regarding this procedure.

## Footnotes

*   **Funding** The author(s) received no financial support for the research, authorship, and/or publication of this article.

*   **Declaration of Conflicting Interests** The authors report no conflicts of interest related to this work.

*   **Disclosure** The authors report no financial disclosures related to this article.

*   This manuscript is generously published free of charge by ISASS, the International Society for the Advancement of Spine Surgery. Copyright © 2022 ISASS. To see more or order reprints or permissions, see [http://ijssurgery.com](http://ijssurgery.com).

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