A 26-Year Evidence Map of Metabolic and Bariatric Surgery in Türkiye: A Systematic Scoping Review with Publication-Family Reconciliation
This systematic scoping review of 191 Turkish publications from 2000 to 2026 reveals a shift toward sleeve gastrectomy dominance and identifies a conservative lower bound of 27,377 unique patients, while highlighting that publication-family overlaps and heterogeneous reporting prevent reliable national pooled safety estimates.
Original paper licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). This is an AI-generated explanation of the paper below. It is not written or endorsed by the authors. For technical accuracy, refer to the original paper. Read full disclaimer
Obesity is more than a matter of weight; it is a complex health challenge that often brings with it a host of other serious conditions, such as type 2 diabetes, high blood pressure, and heart disease. For many people, changing their diet and exercise habits is not enough to reverse these conditions, leading doctors to consider surgical options. These operations, known as metabolic or bariatric surgery, work by changing the size or shape of the stomach and sometimes the intestines to help the body lose weight and regulate blood sugar. Over the last few decades, the tools surgeons use have changed dramatically. Some older techniques have fallen out of favor, while newer, less invasive methods have become the standard. However, because so many hospitals and research groups publish their results, it can be difficult to see the full picture of what is actually happening across a whole country. When different research teams publish reports about the same group of patients, or when the same data is split into multiple articles, it becomes easy to accidentally count the same people twice, creating a distorted view of how many patients have been treated and how well the surgeries are working.
A researcher set out to untangle this web of information by creating a comprehensive map of every study on metabolic and bariatric surgery published in Türkiye between the year 2000 and mid-2026. Their goal was not just to count the number of articles, but to understand the actual number of unique patients represented in that literature and to track how the preferred surgical methods have shifted over time. They faced a significant challenge: the medical literature is full of "publication families," where a single group of patients might be the subject of several different papers published over years, each focusing on a different outcome like weight loss, pregnancy, or long-term complications. If a reader simply added up the patient numbers from every paper, they would be counting the same individuals multiple times. To solve this, the researcher developed a careful method to link these related reports together, treating them as a single family of data rather than separate, independent studies.
After gathering hundreds of reports and filtering out those that did not fit their criteria, the researcher identified 191 unique publications. Of these, 177 were eligible for analysis, containing data on thousands of patients. By carefully reconciling these reports and removing the double-counting, they determined that the literature represented a conservative minimum of at least 27,377 unique patients. This number is significant because it shows that while there are many published reports, the actual number of distinct individuals studied is smaller than the raw count of papers might suggest. The researcher also found that the landscape of surgery in Türkiye has changed drastically. In the early years of their review, up to 2015, the procedures used were quite varied, with a significant number of patients receiving a procedure involving an adjustable band placed around the stomach. However, as time went on, the field shifted dramatically. By the period between 2016 and 2020, a different technique, known as sleeve gastrectomy, had become the dominant method, appearing in more than 90 percent of the reports. This trend continued into the most recent years, with the sleeve procedure remaining the primary choice, while the use of the gastric banding technique effectively disappeared from the published literature.
The study also looked at the results of these surgeries, confirming that weight loss and improvements in metabolic health, such as the remission of diabetes, were commonly reported. However, the researcher could not calculate a single, reliable national rate for surgical complications like bleeding or infection. This was not because the surgeries were unsafe, but because the way different hospitals reported their safety data was inconsistent. Some studies provided exact numbers of events and the total number of patients, while others only gave rounded percentages or combined data in ways that made it impossible to compare them directly. This lack of standardization means that while we know these surgeries are effective for weight loss, we do not yet have a unified, clear picture of the safety risks across the entire country based on the published evidence alone.
The researcher also examined the quality of the evidence, noting that while there were nearly thirty randomized clinical trials included in their review, many of these studies had limitations in how they reported their methods or followed up with patients. This suggests that while there is a growing body of high-quality research, there is still room for improvement in how data is collected and shared. The study concludes that the number of published reports does not equal the number of independent patient groups, and that simply counting papers can lead to a misunderstanding of the scale of medical practice. By mapping the evidence carefully, the researcher has provided a clearer, more accurate foundation for understanding the history and current state of metabolic surgery in Türkiye, highlighting the need for better standardized reporting in the future to ensure that safety data can be reliably compared across different centers.
Drowning in papers in your field?
Get daily digests of the most novel papers matching your research keywords — with technical summaries, in your language.