Acta Dermato-Venereologica 99-9CompleteContent | Page 13
CLINICAL REPORT
Interest in Skin Cancer in Urban Populations: A Retrospective
Analysis of Google Search Terms in Nine Large German Cities
Linda TIZEK 1,2 , Maximilian C. SCHIELEIN 1,2 , Melvin RÜTH 1 , Rolf-Markus SZEIMIES 3 , Wolfgang G. PHILIPP-DORMSTON 4,5 ,
Stephan A. BRAUN 6 , Christine HECKER 7 , Bernadette EBERLEIN 1 , Tilo BIEDERMANN 1 and Alexander ZINK 1
1
Department of Dermatology and Allergy, School of Medicine, Technical University of Munich, 2 The Institute for Medical Information Processing,
Biometry, and Epidemiology, LMU Munich, Munich, 3 Department of Dermatology and Allergology, Vest Clinic, Recklinghausen, 4 Hautzentrum
Koeln, Klinik Links vom Rhein, Cologne, 5 Faculty of Health, University Witten-Herdecke, Witten, 6 Department of Dermatology – General
Dermatology and Venereology, Münster University Medical Center, Muenster, and 7 Department of Dermatology, Nuremberg Hospital North,
Nuremberg, Germany
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 can-
cer”. 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.
Key words: skin cancer; melanoma; non-melanoma skin can-
cer; Google; search analysis; retrospective study; keratinocyte;
risk assessment.
Accepted May 9, 2019; E-published May 10, 2019
Acta Derm Venereol 2019; 99: 797–804.
797
Corr: Alexander Zink, Department of Dermatology and Allergy, School of
Medicine, Technical University of Munich, Biedersteiner Str. 29, DE-80802
Munich, Germany. E-mail: [email protected]
S
kin cancer, including non-melanoma skin cancer
(NMSC) and melanoma, is the most common carci
noma among Caucasians worldwide (1–4), with increa
sing incidence during recent decades (5–9). While the
incidence of NMSC is 18–20 times higher than that of
melanoma (1, 3), melanoma is more often fatal (10, 11).
Thus, skin cancer presents an enormous socioeconomic
burden (12–14), which could be reduced by early detec
tion, diagnosis and treatment (15, 16). Specifically, the in
cidence of NMSC can be reduced through sun-protection
measures (17–19). Despite substantial efforts to compre
hensively implement primary prevention strategies (e.g.
seeking shade, wearing sun protective clothing, using
sun-screen) and secondary prevention strategies (e.g.
regular self-examination, regular dermatological check-
ups, skin cancer screening campaigns) (20), studies have
SIGNIFICANCE
This study examined the Google search volume for skin-
cancer-related terms in 9 German cities. Overall, 3.5 mil-
lion searches related to skin cancer were observed between
July 2014 and June 2018. Most of these searches focused
on the identification of skin cancer (e.g. ABCD and pictures
of skin cancer). In general, the number of search queries
per 100,000 inhabitants was lower in larger cities, such as
Berlin or Hamburg, in comparison with Stuttgart or Muens-
ter. Analysis of the differences in search behavior between
cities could help to identify areas with a high need for tar-
geted prevention campaigns.
shown that utilization of such strategies is not highly
prevalent (21–23), particularly among individuals who
spend a lot of time outdoors (24–27).
One way to investigate reasons for not using skin cancer
prevention measures is to focus on the interest in skin
cancer among the general population (28). As the Internet
is a commonly used source of health information, search
engine analysis represents a novel tool for investigating
the general interest in various topics (16, 28–33). In Ger
many, approximately 90% of inhabitants use the Internet
(34). More specifically, 95% use Google as their primary
search engine (35), and 57% have used the Internet to
search for health-related information (36). For example,
a German study among patients with melanoma reported
that 63% indicated the Internet as the most important
source of media information (37). One US study revealed
a positive correlation between Internet search volume and
the incidence and mortality rates of melanoma and other
common cancers (38). Additional studies have revealed
an increasing number of Google searches related to health
information in recent years (30, 39).
The aim of the present study was to investigate German
inhabitants’ interest in skin cancer, and whether geogra
phical differences in interest have emerged, by analyzing
Google search volumes in 9 German cities. Furthermore,
the number of search queries within each city was com
pared with data from respective cancer registers in order
to determine whether there was a correlation between
interest and cancer incidence rates.
This is an open access article under the CC BY-NC license. www.medicaljournals.se/acta
Journal Compilation © 2019 Acta Dermato-Venereologica.
doi: 10.2340/00015555-3214
Acta Derm Venereol 2019; 99: 797–804