Regional differences and seasonal variation of the burden of skin diseases in southern Germany: a retrospective analysis of internet data

Background: Skin diseases are associated with a considerable burden for patients and their relatives. Not every affected individual, however, seeks medical health care and their families are often forgotten, which makes it challenging to identify all unmet needs. Objectives: This study aimed to identify regional differences and seasonal variations related to dermatology via an internet search and further investigate whether regional factors influence search behaviour. Materials & Methods: A retrospective longitudinal study using Google Ads Keyword Planner was carried out to identify skin disease-related terms throughout Bavaria, southern Germany, from June 2015 to May 2019. Terms were categorized and assessed for regional and seasonal differences. Results: From 976 human skin-related terms, with a total search volume of 9,928,630 queries, 7,988,220 referred to "human skin disease", with a higher search volume in rural compared to urban areas (p = 0.012). Search queries for "allergy" and "human skin diseases" displayed significant seasonality (p>0.001 and p = 0.002, respectively). Conclusion: Future monitoring and assessment of this type of Google data for predefined regional areas could identify specific medical needs and provide timed and targetgroup-oriented medical care and information. These could be beneficial for affected people, their family members, physicians, and public health officials.

Leveraging internet search data to assess prevalence, interest, and unmet needs of sarcoidosis in Germany.

Sarcoidosis is a multisystemic disease of connective tissue with granuloma formation of unknown etiology and unclear prevalence. Internet search data has been shown to correlate with disease incidences and the population's interest as well as seasonal variations. Accordingly, aim of this study was to leverage internet search data on sarcoidosis-related keywords to identify unmet needs, geographical and seasonal factors influencing sarcoidosis and estimating its prevalence. In this retrospective longitudinal study, Google Ads Keyword Planner was used to determine the internet search volume of terms related to sarcoidosis across Germany as a whole and in 17 major German cities between July 2015 and June 2019. Identified keywords were qualitatively categorized, converted into number of searches per 100,000 inhabitants and analyzed including regional and seasonal differences. With 3,068,200 queries and 425 different sarcoidosis-related search terms in the studied time period, the search volume was very high for a rare disease. Most searches (67.9%) related to general disease information with "sarcoidosis", "Löfgren's syndrome", "sarcoidosis lung", "Morbus Boeck" and "neurosarcoidosis" as the top five keywords. Searches per 100,000 inhabitants were comparable in all 17 cities but higher than in Germany as a whole. Overall, the search volume increased from 2015 to 2019 and peaked annually in European springtime with annual lows in European autumn and winter months. The overall high search volume suggests an unmet need for sarcoidosis-related information and a diagnostic gap. Seasonal fluctuations indicate environmental as well as climatic factors that may influence sarcoidosis.

Interest in Sexually Transmitted Infections: Analysis of Web Search Data Terms in Eleven Large German Cities from 2015 to 2019.

Incidence of sexually transmitted infections (STIs) such as chlamydia, gonorrhea, and syphilis has increased in recent years in the US and in European countries. In order to implement effective educational programs, the interests of target populations have to be identified. Since the internet is an important source of information-gathering on health issues, this study investigates web search data in large German cities related to STIs. Google Ads Keyword Planner was used to identify STI-related terms and their search volume in eleven German cities from June 2015 to May 2019. The data obtained were analyzed descriptively with regard to total search volumes, search volumes of specific thematic areas, and search volumes per 100,000 inhabitants. Overall, 741 terms with a total search volume of 5,142,560 queries were identified, with more than 70% of all search queries including a specific disease and "chlamydia" being the overall most often searched term (n = 1,196,160). Time courses of search behavior displayed a continuous interest in STIs with synchronal and national rather than regional peaks. Volumes of search queries lacked periodic patterns. Based on the findings of this study, a more open public discussion about STIs with linkage to increased media coverage and clarification of responsibilities among all STI-treating disciplines concerning management of STIs seem advisable.

Googling for Ticks and Borreliosis in Germany: Nationwide Google Search Analysis From 2015 to 2018.

BACKGROUND: Borreliosis is the most frequently transmitted tick-borne disease in Europe. It is difficult to estimate the incidence of tick bites and associated diseases in the German population due to the lack of an obligation to register across all 16 federal states of Germany. OBJECTIVE: The aim of this study is to show that Google data can be used to generate general trends of infectious diseases on the basis of borreliosis and tick bites. In addition, the possibility of using Google AdWord data to estimate incidences of infectious diseases, where there is inconsistency in the obligation to notify authorities, is investigated with the perspective to facilitate public health studies. METHODS: Google AdWords Keyword Planner was used to identify search terms related to ticks and borreliosis in Germany from January 2015 to December 2018. The search volume data from the identified search terms was assessed using Excel version 15.23. In addition, SPSS version 24.0 was used to calculate the correlation between search volumes, registered cases, and temperature. RESULTS: A total of 1999 tick-related and 542 borreliosis-related search terms were identified, with a total of 209,679,640 Google searches in all 16 German federal states in the period under review. The analysis showed a high correlation between temperature and borreliosis (r=0.88), and temperature and tick bite (r=0.83), and a very high correlation between borreliosis and tick bite (r=0.94). Furthermore, a high to very high correlation between Google searches and registered cases in each federal state was observed (Brandenburg r=0.80, Mecklenburg-West Pomerania r= 0.77, Saxony r= 0.74, and Saxony-Anhalt r=0.90; all P<.001). CONCLUSIONS: Our study provides insight into annual trends concerning interest in ticks and borreliosis that are relevant to the German population exemplary in the data of a large internet search engine. Public health studies collecting incidence data may benefit from the results indicating a significant correlation between internet search data and incidences of infectious diseases.

Influence of Climate on Google Internet Searches for Pruritus Across 16 German Cities: Retrospective Analysis.

BACKGROUND: The burden of pruritus is high, especially among patients with dermatologic diseases. Identifying trends in pruritus burden and people's medical needs is challenging, since not all affected people consult a physician. OBJECTIVE: The purpose of this study was to investigate pruritus search behavior trends in Germany and identify associations with weather factors. METHODS: Google AdWords Keyword Planner was used to quantify pruritus-related search queries in 16 German cities from August 2014 to July 2018. All identified keywords were qualitatively categorized and pruritus-related terms were descriptively analyzed. The number of search queries per 100,000 inhabitants of each city was compared to environmental factors such as temperature, humidity, particulate matter 10 micrometers or less in diameter (PM10), and sunshine duration to investigate potential correlations. RESULTS: We included 1150 pruritus-related keywords, which resulted in 2,851,290 queries. "Pruritus" (n=115,680) and "anal pruritus" (n=102,390) were the most-searched-for keywords. Nearly half of all queries were related to the category localization, with Berlin and Munich having a comparatively high proportion of people that searched for pruritus in the genital and anal areas. People searched more frequently for information on chronic compared to acute pruritus. The most populated cities had the lowest number of queries per 100,000 inhabitants (Berlin, n=13,641; Hamburg, n=18,303; and Munich, n=21,363), while smaller cities (Kiel, n=35,027; and Freiburg, n=39,501) had the highest. Temperature had a greater effect on search query number (beta -7.94, 95% CI -10.74 to -5.15) than did PM10 (beta -5.13, 95% CI -7.04 to -3.22), humidity (beta 4.73, 95% CI 2.70 to 6.75), or sunshine duration (beta 0.66, 95% CI 0.36 to 0.97). The highest relative number of search queries occurred during the winter (ie, December to February). CONCLUSIONS: By taking into account the study results, Google data analysis helps to examine people's search frequency, behavior, and interest across cities and regions. The results indicated a general increase in search queries during the winter as well as differences across cities located in the same region; for example, there was a decline in search volume in Saarbrucken, while there were increases in Cologne, Frankfurt, and Dortmund. In addition, the detected correlation between search volume and weather data seems to be valuable in predicting an increase in pruritus burden, since a significant association with rising humidity and sunshine duration, as well as declining temperature and PM10, was found. Accordingly, this is an unconventional and inexpensive method to identify search behavior trends and respective inhabitants' needs.

Interest in Skin Cancer in Urban Populations: A Retrospective Analysis of Google Search Terms in Nine Large German Cities.

Skin cancer is a major public health issue, which could be reduced through prevention programmes. How-ever, prevention utilization is not very prevalent. It is therefore important to understand individuals' interest in skin cancer. Google AdWords Keyword Planner was used to identify the search volume of terms relating to skin cancer in 9 German cities between July 2014 and June 2018. From a total of 1,203 identified keywords, 1,047 search terms were related to skin cancer, which had a search volume of 3,460,980 queries for the study period. Most terms referred to "identifying skin cancer". For melanoma, the number of Google searches per 100,000 inhabitants correlated with the cancer registry data for melanoma incidence rates (men: r = 0.810, women: r = 0.569). Assessment of this data for the different cities further enabled identification of regional variations, which could help to identify areas with a high need for targeted prevention campaigns.

What Do Germans Want to Know About Skin Cancer? A Nationwide Google Search Analysis From 2013 to 2017.

BACKGROUND: Experts worldwide agree that skin cancer is a global health issue, but only a few studies have reported on world populations' interest in skin cancer. Internet search data can reflect the interest of a population in different topics and thereby identify what the population wants to know. OBJECTIVE: Our aim was to assess the interest of the German population in nonmelanoma skin cancer and melanoma. METHODS: Google AdWords Keyword Planner was used to identify search terms related to nonmelanoma skin cancer and melanoma in Germany from November 2013 to October 2017. The identified search terms were assessed descriptively using SPSS version 24.0. In addition, the search terms were qualitatively categorized. RESULTS: A total of 646 skin cancer-related search terms were identified with 19,849,230 Google searches in the period under review. The search terms with the highest search volume were "skin cancer" (n=2,388,500, 12.03%), "white skin cancer" (n=2,056,900, 10.36%), "basalioma" (n=907,000, 4.57%), and "melanoma" (n=717,800, 3.62%). The most searched localizations of nonmelanoma skin cancer were "nose" (n=93,370, 38.99%) and "face" (n=53,270, 22.24%), and the most searched of melanoma were "nails" (n=46,270, 70.61%) and "eye" (n=10,480, 15.99%). The skin cancer‒related category with the highest search volume was "forms of skin cancer" (n=10,162,540, 23.28%) followed by "skin alterations" (n=4,962,020, 11.36%). CONCLUSIONS: Our study provides insight into terms and fields of interest related to skin cancer relevant to the German population. Furthermore, temporal trends and courses are shown. This information could aid in the development and implementation of effective and sustainable awareness campaigns by developing information sources targeted to the population's broad interest or by implementing new Internet campaigns.