Wang T. et al., 2020: Use of Baidu Index to Track Chinese Online Behavior and Interest in Kidney Stones
Wang T, Xia Q, Chen X, Jin X.
Department of Urology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong, People's Republic of China.
Background and aim: Baidu, currently the top online search tool in China, has developed an internet search trends gathering and analysis tool called the Baidu Index. The aim of this study was to explore the value of the Baidu Index for monitoring online kidney stones-related information-seeking behavior and understanding of population features and priorities in China.
Materials and methods: The Baidu Index was queried using the term "kidney stones" for the period 2014-2018. The search volume was recorded as well as a demand graph, with a geographic and demographic distribution. For surgical treatment modalities, the medical term "extracorporeal shock wave lithotripsy (ESWL)" was analyzed and then compared to the term "kidney stone surgery" to assess changes.
Results: The search trend for the term "kidney stones" remained sustained growth over time. Searches were mostly presented by the age 20-49, in males in the south of China. The demand graph indicated that the diagnosis, followed by the treatment, and dietary control of kidney stones had received the most attention. The search volume related to ESWL showed a similar increasing trend, but was searched with a greater volume than the term "kidney stone surgery" for most of the last 5 years.
Conclusion: The Baidu Index is a useful tool to track online health information-seeking behavior of internet users in China. The geographic and demographic characteristics in kidney stones seem to be reflected in online search trend data to some extent.
Keywords: Baidu Index; extracorporeal shock wave lithotripsy; kidney stone surgery; kidney stones; search engine.
Risk Manag Healthc Policy. 2020 Jul 3;13:705-712. doi: 10.2147/RMHP.S245822. eCollection 2020. PMID: 3269492. FREE ARTICLE
The “Baidu Index” used by the authors is comparable to “Google trends”. Google is not available in China as they moved out of China in 2010. Here you can read why: https://www.theatlantic.com/technology/archive/2016/01/why-google-quit-china-and-why-its-heading-back/424482/
Both, the Baidu Index and Google trends do not give the absolute search volume numbers, but a search volume index. In Google trends the peak search activity is graded as100% and all other activities at all other time periods are presented relative to that peak. “The Baidu Index represents a normalized search volume for selected keywords, instead of the absolute search volume.” In the present article the normalisation is not specified.
Getting many data is relatively easy nowadays. The problem for the authors and the readers is how interpret them.
If you enter >CircumcisionUrolithiasisrends
https://trends.google.com/trends/explore?date=today%205-y&geo=US&q=circumcision,urolithiasis you get this:
Entering the terms in a different sequence
https://trends.google.com/trends/explore?date=today%205-y&geo=US&q=urolithiasis,cicumcision produces the following graph
Difficult to judge what is of more public interest. There will be a correct interpretation of the two seemingly different graphs, but it is not visible at first glance. The authors of the present paper may have seen something similar.
They were aware of the strong downward and the concurrent upward trend of SWL and RIRS resp. However, “the search terms percutaneous nephrolithotomy and ureteroscopy lithotripsy were not included in the Baidu Index keywords database due to the low search volume.”
“We found that the specific treatment modality “ESWL” was searched more frequently than the terminology “kidney stone surgery” over most of the past 5 years.” and “ESWL search volume maintained a stable growth despite a considerable decline in actual clinical practice …” So the index does not reflect a urological reality.
It seems to me that the conclusions are weak because interpretation of the data is speculative.