Google Internet searches related to inflammatory arthritis: An observational study using Google Trends data.

OBJECTIVE: The Internet has transformed how patients access health information. We examined Google search engine data to understand which aspects of health are most often searched for in combination with inflammatory arthritis (IA). METHODS: Using Google Trends data (2011-2022) we determined the relative popularity of searches for 'patient symptoms' (pain, fatigue, stiffness, mood, work) and 'treat-to-target' (disease-modifying drugs, steroids, swelling, inflammation) health domains made with rheumatoid arthritis (RA), psoriatic arthritis (PsA), and axial spondyloarthritis (AxSpA) in the UK/USA. Google Trends normalises searches by popularity over time and region, generating 0-100 scale relative search volumes (RSV; 100 represents the time-point with most searches). Up to five search term combinations can be compared. RESULTS: In all IA forms, pain was the most popular patient symptom domain. UK/USA searches for pain gave mean RSVs of 58/79, 34/51, and 39/63 with RA, PsA, and AxSpA; mean UK/USA RSVs for other patient symptom domains ranged 2-7/2-8. Methotrexate was the most popular treat-to-target search term with RA/PsA in the UK (mean 28/21) and USA (mean 63/33). For AxSpA, inflammation was most popular (mean UK/USA 9/34). Searches for pain were substantially more popular than searches for methotrexate in RA and PsA, and inflammation in AxSpA. Searches increased over time. CONCLUSIONS: Pain is the most popular search term used with IA in Google searches in the UK/USA, supporting surveys/qualitative studies highlighting the importance of improving pain to patients with IA. Routine pain assessments should be embedded within treat-to-target strategies to ensure patient perspectives are considered.

Association Between Prosuicide Website Searches Through Google and Suicide Death in the United States From 2010 to 2021: Lagged Time-Series Analysis.

BACKGROUND:  The rate of suicide death has been increasing, making understanding risk factors of growing importance. While exposure to explicit suicide-related media, such as description of means in news reports or sensationalized fictional portrayal, is known to increase population suicide rates, it is not known whether prosuicide website forums, which often promote or facilitate information about fatal suicide means, are related to change in suicide deaths overall or by specific means. OBJECTIVE:  This study aimed to estimate the association of the frequency of Google searches of known prosuicide web forums and content with death by suicide over time in the United States, by age, sex, and means of death. METHODS:  National monthly Google search data for names of common prosuicide websites between January 2010 and December 2021 were extracted from Google Health Trends API (application programming interface). Suicide deaths were identified using the CDC (Centers for Disease Control and Prevention) National Vital Statistics System (NVSS), and 3 primary means of death were identified (poisoning, suffocation, and firearm). Distributed lag nonlinear models (DLNMs) were then used to estimate the lagged association between the number of Google searches on suicide mortality, stratified by age, sex, and means, and adjusted for month. Sensitivity analyses, including using autoregressive integrated moving average (ARIMA) modeling approaches, were also conducted. RESULTS:  Months in the United States in which search rates for prosuicide websites increased had more documented deaths by intentional poisoning and suffocation among both adolescents and adults. For example, the risk of poisoning suicide among youth and young adults (age 10-24 years) was 1.79 (95% CI 1.06-3.03) times higher in months with 22 searches per 10 million as compared to 0 searches. The risk of poisoning suicide among adults aged 25-64 was 1.10 (95% CI 1.03-1.16) times higher 1 month after searches reached 9 per 10 million compared with 0 searches. We also observed that increased search rates were associated with fewer youth suicide deaths by firearms with a 3-month time lag for adolescents. These models were robust to sensitivity tests. CONCLUSIONS:  Although more analysis is needed, the findings are suggestive of an association between increased prosuicide website access and increased suicide deaths, specifically deaths by poisoning and suffocation. These findings emphasize the need to further investigate sites containing potentially dangerous information and their associations with deaths by suicide, as they may affect vulnerable individuals.

Trending ticks: using Google Trends data to understand tickborne disease prevention.

Introduction: Ticks and pathogens they carry seriously impact human and animal health, with some diseases like Lyme and Alpha-gal syndrome posing risks. Searching for health information online can change people's health and preventive behaviors, allowing them to face the tick risks. This study aimed to predict the potential risks of tickborne diseases by examining individuals' online search behavior. Methods: By scrutinizing the search trends across various geographical areas and timeframes within the United States, we determined outdoor activities associated with potential risks of tick-related diseases. Google Trends was used as the data collection and analysis tool due to its accessibility to big data on people's online searching behaviors. We interact with vast amounts of population search data and provide inferences between population behavior and health-related phenomena. Data were collected in the United States from April 2022 to March 2023, with some terms about outdoor activities and tick risks. Results and Discussion: Results highlighted the public's risk susceptibility and severity when participating in activities. Our results found that searches for terms related to tick risk were associated with the five-year average Lyme Disease incidence rates by state, reflecting the predictability of online health searching for tickborne disease risks. Geographically, the results revealed that the states with the highest relative search volumes for tick-related terms were predominantly located in the Eastern region. Periodically, terms can be found to have higher search records during summer. In addition, the results showed that terms related to outdoor activities, such as "corn maze," "hunting," "u-pick," and "park," have moderate associations with tick-related terms. This study provided recommendations for effective communication strategies to encourage the public's adoption of health-promoting behaviors. Displaying warnings in the online search results of individuals who are at high risk for tick exposure or collaborating with outdoor activity locations to disseminate physical preventive messages may help mitigate the risks associated with tickborne diseases.

Ostomy Information on the Internet-Is It Good Enough?

PURPOSE: The aim of this study was to determine which internet search engines and keywords patients with ostomies utilize, to identify the common websites using these terms, to determine what aspects of information they wanted, and to perform a quality and readability assessment for these websites. DESIGN: A cross-sectional survey of persons with ostomies to identify search engines and terms, followed by a structured assessment of the quality and readability of the identified web pages. SUBJECT AND SETTINGS: The sample comprised 20 hospitalized patients with ostomies cared for on a colorectal surgical ward of a tertiary care hospital located in Melbourne, Australia. There were 15 (75%) adult males and 5 (25%) adult females; their mean age was 52.2 years. Participants were surveyed between August and December 2020. METHODS: Patients with newly formed ostomies were surveyed about which search engines and keywords they would use to look for information and for which questions regarding ostomies they wanted answers. In addition, 2 researchers then performed independent searches using the search terms identified by patient participants. These searches were conducted in August 2021, with the geographical location set to Australia. The quality of the websites was graded using the DISCERN, Ensuring Quality Information for Patients, and Quality Evaluation Scoring Tool scoring assessments, and their readability was graded using the Flesch Reading Ease Score tool. RESULTS: Participants used Google as their primary search engine. Four keywords/phrases were identified: stoma for bowel surgery, ileostomy, colostomy, and caring for stoma. Multiple web pages were identified, 8 (21%) originated from Australia, 7 (18%) were from the United Kingdom, and 23 (61%) were from the United States. Most web pages lacked recent updates; only 18% had been undated within the last 12 months. The overall quality of the online information on ostomies was moderate with an average level of readability, deemed suitable for patient educational purposes. CONCLUSIONS: Information for persons living with an ostomy can be obtained from multiple web pages, and many sites have reasonable quality and are written at a suitable level. Unfortunately, these websites are rarely up-to-date and may contain advice that may not be applicable to individual patients.

Emerging Trends in Information-Seeking Behavior for Alpha-Gal Syndrome: Infodemiology Study Using Time Series and Content Analysis.

BACKGROUND: Alpha-gal syndrome is an emerging allergy characterized by an immune reaction to the carbohydrate molecule alpha-gal found in red meat. This unique food allergy is likely triggered by a tick bite. Cases of the allergy are on the rise, but prevalence estimates do not currently exist. Furthermore, varying symptoms and limited awareness of the allergy among health care providers contribute to delayed diagnosis, leading individuals to seek out their own information and potentially self-diagnose. OBJECTIVE: The study aimed to (1) describe the volume and patterns of information-seeking related to alpha-gal, (2) explore correlations between alpha-gal and lone star ticks, and (3) identify specific areas of interest that individuals are searching for in relation to alpha-gal. METHODS: Google Trends Supercharged-Glimpse, a new extension of Google Trends, provides estimates of the absolute volume of searches and related search queries. This extension was used to assess trends in searches for alpha-gal and lone star ticks (lone star tick, alpha gal, and meat allergy, as well as food allergy for comparison) in the United States. Time series analyses were used to examine search volume trends over time, and Spearman correlation matrices and choropleth maps were used to explore geographic and temporal correlations between alpha-gal and lone star tick searches. Content analysis was performed on related search queries to identify themes and subcategories that are of interest to information seekers. RESULTS: Time series analysis revealed a rapidly increasing trend in search volumes for alpha-gal beginning in 2015. After adjusting for long-term trends, seasonal trends, and media coverage, from 2015 to 2022, the predicted adjusted average annual percent change in search volume for alpha-gal was 33.78%. The estimated overall change in average search volume was 627%. In comparison, the average annual percent change was 9.23% for lone star tick, 7.34% for meat allergy, and 2.45% for food allergy during this time. Geographic analysis showed strong significant correlations between alpha-gal and lone star tick searches especially in recent years (ρ=0.80; P<.001), with primary overlap and highest search rates found in the southeastern region of the United States. Content analysis identified 10 themes of primary interest: diet, diagnosis or testing, treatment, medications or contraindications of medications, symptoms, tick related, specific sources of information and locations, general education information, alternative words for alpha-gal, and unrelated or other. CONCLUSIONS: The study provides insights into the changing information-seeking patterns for alpha-gal, indicating growing awareness and interest. Alpha-gal search volume is increasing at a rapid rate. Understanding specific questions and concerns can help health care providers and public health educators to tailor communication strategies. The Google Trends Supercharged-Glimpse tool offers enhanced features for analyzing information-seeking behavior and can be valuable for infodemiology research. Further research is needed to explore the evolving prevalence and impact of alpha-gal syndrome.

Leveraging web search data in Germany to identify unmet needs of contraceptives on a population-based level: A longitudinal retrospective study.

BACKGROUND: There are a variety of possible contraceptives available. While medical advice is an important resource for selecting the individual contraceptive, previous research has shown that the Internet has become an increasingly important source of health care information. OBJECTIVES: This study aims to identify key trends in contraception-related web searches in Germany and thus allows conclusions about preferences and unmet needs with regard to pregnancy prevention. DESIGN: Longitudinal retrospective study. METHODS: Google Ads Keyword Planner was used to identify contraception-related keywords and their search volume in Germany and all federal states between 2018 and 2021. The keywords were categorized based on gender, hormonal/non-hormonal, and different contraceptive methods. Search volume and categories were analyzed for temporal trends, regional differences, and underlying socioeconomic variables. RESULTS: The 1481 contraception-related keywords corresponded to 15,081,760 searches. In total, a 56% increase in searches/100,000 inhabitants was observed. Highest mean search volume was observed in categories "woman," "woman/non-hormonal" and "woman/non-hormonal/barrier," respectively, and in the federal state Hamburg, while the lowest was seen in North Rhine-Westphalia. CONCLUSION: The increase in search volume reflects a high interest in contraception, particularly in non-hormonal female methods. This stands in contrast to the limited number of effective non-hormonal contraceptives available and points to an unmet need. In addition, the low search volume for male contraceptives demonstrates gender-specific responsibilities regarding family planning in German society.

Analyzing Google search volume to identify preferences and unmet needs in contraception in German societyContraception is a topic that occupies many people in their daily lives. There is a wide range of different contraceptives available. The decision for a particular contraceptive can be made with the help of a consultation with a gynecologist or through other sources, such as the Internet. Research has shown that the Internet has become an important source for obtaining health information. This study aims to identify key trends in contraception-related web searches in Germany and thus allows conclusions about preferences and unmet needs with regard to pregnancy prevention. Google Ads Keyword Planner was used to identify contraception-related keywords and their search volume in Germany and all federal states between 2018 and 2021. The keywords were assigned to different categories based on whether the woman or the man uses the contraceptive, whether the contraceptive methods contain hormones or no hormones, and which exact contraceptive methods are associated with the search term. The search volume was analyzed in terms of trends over time, regional differences in Germany and socioeconomic variables. A 56% increase in searches per 100,000 inhabitants was observed. The highest mean search volume was observed in the category woman, followed by female non-hormonal contraceptives and within that category, the contraceptive method "barrier." The study shows that there is a high interest in contraception, especially in non-hormonal female contraceptives. These results contrast with the limited number of non-hormonal and effective contraceptive methods available. In addition, the low search volume in the category man shows that women are the main responsible party in terms of contraception in German society.

Natural childbirth and cesarean section - descriptive analysis of queries in Google search engine.

OBJECTIVES: The use of internet-based search engines for health information is very popular and common. The Internet has become an important source of health information and has a considerable impact on patient's decision making process. Knowledge of pregnant women about childbirth comes from health professionals and personal experiences described by friends or family members. There is a growing interest in digital sources used by pregnant women. Analysis of queries related to regarding to natural childbirth and cesarean section in the Google search engine. MATERIAL AND METHODS: In this infodemiology, descriptive study tool "AlsoAsked" was used. This is a tool for analyzing data appearing in Google search results. "AlsoAsked" search was conducted on April 19, 2023. Search phrases "natural childbirth" and "cesarean section" in polish language were used. Questions that were typed into the Google search engine, ranked according to popularity (volume) and thematic connections have been discussed. RESULTS: The most frequently asked questions were related to the course and duration of labor as well as the preparation for labor and cesarean section (CS). Comparison between a natural labour and CS in the context of safety and pain received a great deal of attention. CONCLUSIONS: The most popular questions regarding CS were related to elective CS and indications for it. Some questions concerned the connection between labor and clinical state of a newborn.

Online searches to evaluate misinformation can increase its perceived veracity.

Considerable scholarly attention has been paid to understanding belief in online misinformation1,2, with a particular focus on social networks. However, the dominant role of search engines in the information environment remains underexplored, even though the use of online search to evaluate the veracity of information is a central component of media literacy interventions3-5. Although conventional wisdom suggests that searching online when evaluating misinformation would reduce belief in it, there is little empirical evidence to evaluate this claim. Here, across five experiments, we present consistent evidence that online search to evaluate the truthfulness of false news articles actually increases the probability of believing them. To shed light on this relationship, we combine survey data with digital trace data collected using a custom browser extension. We find that the search effect is concentrated among individuals for whom search engines return lower-quality information. Our results indicate that those who search online to evaluate misinformation risk falling into data voids, or informational spaces in which there is corroborating evidence from low-quality sources. We also find consistent evidence that searching online to evaluate news increases belief in true news from low-quality sources, but inconsistent evidence that it increases belief in true news from mainstream sources. Our findings highlight the need for media literacy programmes to ground their recommendations in empirically tested strategies and for search engines to invest in solutions to the challenges identified here.

Using Google Trends for Evaluation of Public Interest in Female Genital Aesthetic Procedures.

BACKGROUND: Genital aesthetics is a treatment that is increasing in popularity. OBJECTIVE: To clarify public interest in genital aesthetic procedures among women between 2004 and 2022. MATERIALS AND METHODS: In total, 12 terms including labiaplasty, vaginoplasty, perineoplasty, laser vaginal rejuvenation, labia cosmetic surgery, vaginal cosmetic surgery, vaginal tightening, genital bleaching, hymenoplasty, clitoroplasty, labiaplasty cost, and vaginal laser were reviewed. To evaluate public attention to female genital aesthetic procedures between January 1, 2004, and January 1, 2022, three 6-year periods were compared about the abovementioned 12 terms. RESULTS: Public attention to labiaplasty and hymenoplasty was significantly higher in 2010 to 2016 than in 2004 to 2010 and 2016 to 2022. Vaginoplasty, laser vaginal rejuvenation, and labia cosmetic surgery terms were researched significantly less in 2010 to 2016 and 2016 to 2022 than in 2004 to 2010 (p = .001). Public interest in vaginal tightening and labiaplasty cost significantly increased from 2004 to 2022. Finally, the term vaginal laser was researched most between 2016 and 2022 (p = .001). CONCLUSION: This study found that public attention to labiaplasty cost and vaginal tightening continuously increased between 2004 and 2022. In addition, public interest in the term vaginal laser significantly increased after 2016. By contrast, vaginoplasty, laser vaginal rejuvenation, and labia cosmetic surgery terms were researched significantly less after 2010.

Online public interest in smoking and lung cancer: A comparative study in Google Trends.

BACKGROUND: Lung cancer is the leading cause of cancer death globally. There is a causal relationship between smoking and lung cancer; nearly 90% of cases are caused by cigarette smoking. AIM: To investigate the public interest in the relationship between lung cancer and tobacco smoking through an analysis of searches in Google Trends over the past 16 years. MATERIAL AND METHODS: We conducted a systematic search through Google Trends using the search terms "lung cancer" and "smoking" to identify the numbers of lung cancer and tobacco smoking searches in populations from Turkey, the United States, and the whole world between January 1, 2004 and December 31, 2019. RESULTS: Online searches that reflect public awareness are nearly identical for both lung cancer and smoking; however, there is an inverse correlation between population interest and incidences of lung cancer and smoking. Furthermore, the numbers of searches on lung cancer and smoking decrease gradually in Turkey, in the world, and in the United States over the years, displaying a slight seasonal pattern. CONCLUSION: Informative and educational campaigns covering the whole year are required to raise awareness of the relationship between lung cancer and smoking and keep people argus-eyed.

Providing early indication of regional anomalies in COVID-19 case counts in England using search engine queries.

Prior work has shown the utility of using Internet searches to track the incidence of different respiratory illnesses. Similarly, people who suffer from COVID-19 may query for their symptoms prior to accessing the medical system (or in lieu of it). To assist in the UK government's response to the COVID-19 pandemic we analyzed searches for relevant symptoms on the Bing web search engine from users in England to identify areas of the country where unexpected rises in relevant symptom searches occurred. These were reported weekly to the UK Health Security Agency to assist in their monitoring of the pandemic. Our analysis shows that searches for "fever" and "cough" were the most correlated with future case counts during the initial stages of the pandemic, with searches preceding case counts by up to 21 days. Unexpected rises in search patterns were predictive of anomalous rises in future case counts within a week, reaching an Area Under Curve of 0.82 during the initial phase of the pandemic, and later reducing due to changes in symptom presentation. Thus, analysis of regional searches for symptoms can provide an early indicator (of more than one week) of increases in COVID-19 case counts.

Associations between COVID-19 mobility restrictions and economic, mental health, and suicide-related concerns in the US using cellular phone GPS and Google search volume data.

During the COVID-19 pandemic, US populations have experienced elevated rates of financial and psychological distress that could lead to increases in suicide rates. Rapid ongoing mental health monitoring is critical for early intervention, especially in regions most affected by the pandemic, yet traditional surveillance data are available only after long lags. Novel information on real-time population isolation and concerns stemming from the pandemic's social and economic impacts, via cellular mobility tracking and online search data, are potentially important interim surveillance resources. Using these measures, we employed transfer function model time-series analyses to estimate associations between daily mobility indicators (proportion of cellular devices completely at home and time spent at home) and Google Health Trends search volumes for terms pertaining to economic stress, mental health, and suicide during 2020 and 2021 both nationally and in New York City. During the first pandemic wave in early-spring 2020, over 50% of devices remained completely at home and searches for economic stressors exceeded 60,000 per 10 million. We found large concurrent associations across analyses between declining mobility and increasing searches for economic stressor terms (national proportion of devices at home: cross-correlation coefficient (CC) = 0.6 (p-value <0.001)). Nationally, we also found strong associations between declining mobility and increasing mental health and suicide-related searches (time at home: mood/anxiety CC = 0.53 (<0.001), social stressor CC = 0.51 (<0.001), suicide seeking CC = 0.37 (0.006)). Our findings suggest that pandemic-related isolation coincided with acute economic distress and may be a risk factor for poor mental health and suicidal behavior. These emergent relationships warrant ongoing attention and causal assessment given the potential for long-term psychological impact and suicide death. As US populations continue to face stress, Google search data can be used to identify possible warning signs from real-time changes in distributions of population thought patterns.

A Google Trends™ Analysis of Bladder Cancer: Determining Awareness Campaign Success, and Patients' Needs in Clinical Management.

OBJECTIVE: We aimed to determine the interest and changing trends over time in the diagnosis and treatment of bladder cancer and its awareness campaign by examining the Google Trends application as an indicator of people's interest globally. METHODS: Using the Google Trends application, we determined the yearly and country-based relative search volumes of the term "bladder tumor" and of the methods used in the diagnosis and treatment of bladder cancer in the period from January 2004 to December 2019. We compared the median relative search volumes found in the period 2004-2011 (Period 1) with those found in the period 2012-2019 (Period 2). RESULTS: We found that the median relative search volume for bladder cancer decreased in period 2 and this was parallel to the decrease in the incidence rates in North America and Australia (p<0.001). We found that the bladder cancer awareness month did not cause an increase in the online interest (p>0.05). We found that the median relative search volumes of diagnostic cystoscopy and cytology were higher than those of molecular markers and imaging methods in line with guidelines (p<0.001). Also, TURBT was the most sought-term among treatment methods with increasing popularity in the second period (p<0.001). CONCLUSION: People use the internet intensively to search for information about bladder cancer. We think that several types of web-based applications such as "Google Trends" can help determine the behavioural patterns and tendencies of bladder cancer patients and affect the clinical decision-making processes, as well as readily determining the impact of cancer awareness campaigns to bring about an increased awareness in the society for the recognition of the importance of an early diagnosis.

The relationship between Google search interest for pulmonary symptoms and COVID-19 cases using dynamic conditional correlation analysis.

This study aims to evaluate the monitoring and predictive value of web-based symptoms (fever, cough, dyspnea) searches for COVID-19 spread. Daily search interests from Turkey, Italy, Spain, France, and the United Kingdom were obtained from Google Trends (GT) between January 1, 2020, and August 31, 2020. In addition to conventional correlational models, we studied the time-varying correlation between GT search and new case reports; we used dynamic conditional correlation (DCC) and sliding windows correlation models. We found time-varying correlations between pulmonary symptoms on GT and new cases to be significant. The DCC model proved more powerful than the sliding windows correlation model. This model also provided better at time-varying correlations (r ≥ 0.90) during the first wave of the pandemic. We used a root means square error (RMSE) approach to attain symptom-specific shift days and showed that pulmonary symptom searches on GT should be shifted separately. Web-based search interest for pulmonary symptoms of COVID-19 is a reliable predictor of later reported cases for the first wave of the COVID-19 pandemic. Illness-specific symptom search interest on GT can be used to alert the healthcare system to prepare and allocate resources needed ahead of time.

Decreased Global Interest in Oral Cancer During the COVID-19 Pandemic.

OBJECTIVE: Oral cancer is one of the most common malignancies in developing countries, but studies using global data are scarce. The aim of this study is to analyze the search interests for oral cancer using mouth cancer, tongue cancer, gum cancer, and lip cancer as common keywords. METHODS: Internet searches relating to oral cancer from 2010 to 2020, from 250 countries and dependent areas, were retrieved from Google Trends. Color densities in a heat map were used to show geographic differences. Kruskal-Wallis test with post hoc Dunn's analysis was used to perform yearly comparisons of searches for mouth cancer, tongue cancer, gum cancer, and lip cancer. Search results within 2020 were also compared to determine differences. Forecasting searches from 2021 to 2022 were done by fitting time series models. RESULTS: From 29 of 250 (11.6%) countries, the highest search values were observed for mouth cancer in Sri Lanka, Qatar, Bangladesh, Finland, Netherlands, Spain, and France. Compared to 2020, greater searches were seen in 2018 (Mdn = 91%, P = 0.023) and 2019 (Mdn = 94%, P = 0.012) for mouth cancer, and 2019 (Mdn = 17%, P = 0.035) for lip cancer. The relative search volumes for gum cancer and lip cancer were substantially lower than mouth cancer during the COVID-19 pandemic. CONCLUSION: Higher-income countries tend to be more interested in seeking information about oral cancer. Noteworthy decline in the interest in seeking information online for oral cancer may have crucial implications during the COVID-19 pandemic. Google Trends offer an invaluable and inexpensive means for oral cancer surveillance and health-seeking behavior. 
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Measuring Public Concern About COVID-19 in Japanese Internet Users Through Search Queries: Infodemiological Study.

BACKGROUND: COVID-19 has disrupted lives and livelihoods and caused widespread panic worldwide. Emerging reports suggest that people living in rural areas in some countries are more susceptible to COVID-19. However, there is a lack of quantitative evidence that can shed light on whether residents of rural areas are more concerned about COVID-19 than residents of urban areas. OBJECTIVE: This infodemiology study investigated attitudes toward COVID-19 in different Japanese prefectures by aggregating and analyzing Yahoo! JAPAN search queries. METHODS: We measured COVID-19 concerns in each Japanese prefecture by aggregating search counts of COVID-19-related queries of Yahoo! JAPAN users and data related to COVID-19 cases. We then defined two indices-the localized concern index (LCI) and localized concern index by patient percentage (LCIPP)-to quantitatively represent the degree of concern. To investigate the impact of emergency declarations on people's concerns, we divided our study period into three phases according to the timing of the state of emergency in Japan: before, during, and after. In addition, we evaluated the relationship between the LCI and LCIPP in different prefectures by correlating them with prefecture-level indicators of urbanization. RESULTS: Our results demonstrated that the concerns about COVID-19 in the prefectures changed in accordance with the declaration of the state of emergency. The correlation analyses also indicated that the differentiated types of public concern measured by the LCI and LCIPP reflect the prefectures' level of urbanization to a certain extent (ie, the LCI appears to be more suitable for quantifying COVID-19 concern in urban areas, while the LCIPP seems to be more appropriate for rural areas). CONCLUSIONS: We quantitatively defined Japanese Yahoo users' concerns about COVID-19 by using the search counts of COVID-19-related search queries. Our results also showed that the LCI and LCIPP have external validity.