Identifying Relevant Disease Characteristics Regarding Psoriasis in Germany: A Retrospective Web Search Data Analysis (Preprint)

BACKGROUND Little is known about what people with psoriasis are interested in when they search the web. As the Internet is becoming increasingly relevant as a source of information for health-related questions, the monitoring of online search behavior allows the assessment of interest in a disease on a more representative level by including people outside of medical settings. OBJECTIVE This study aims to reveal relevant aspects regarding psoriasis for people consulting the web. METHODS Google Ads Keyword Planner was used to select and evaluate relevant keywords for ‘psoriasis’ in the study period from September 2016 to August 2020. All keywords were qualitatively reviewed and descriptively analyzed in eleven categories. The study considered the search volume for all of Germany with German as the language preference. One-way analysis of variance and Pearson’s correlation coefficient were used to assess differences in the German states. RESULTS Among 11,170,740 German language Google searches on the topic of psoriasis, the keyword with the overall highest search volume was the German lay term for psoriasis “Schuppenflechte” (n=3,634,000; 32.5%), followed by “psoriasis” (n=2,675,600; 24.0%) and “psoriasis scalp” (n=369,200; 3.3%). In the general category, the most commonly searched for disease aspect related to the possible contagiousness of psoriasis (n=122,040). “Head” (51.1%), followed by “nails” (15.9%), “hands” (8.8%), “feet” (7.8%), and “genital/anal area” (6.1%), was the most frequently searched for localization. Pustular forms of psoriasis were overrepresented in the search volume relative to their frequency in the literature. Almost half of the search terms for therapy were represented by keywords related to alternative care and phytotherapy. Less than one percent of queries on therapy dealt with biologics. Significant differences between the federal states could be established for search volumes on treatment options (P<.001). CONCLUSIONS Queries on pustular forms and difficult-to-treat areas gained high online interest, which suggests a subjectively higher burden of disease or underdiagnosis. Concerning therapy, people most notably consulted the web for alternative therapy options instead of guideline-conform therapies. This suggests possible therapy dissatisfaction, lack of patient information, or lack of access to guideline-conform therapy options. The possible infectiousness of psoriasis seems to remain an issue in the general population and should be continously addressed to reduce stigmatization.