This book constitutes the proceedings of the 9th International Conference on Health Information Science, HIS 2020, which took place in Amsterdam, The Netherlands, during October 20-23, 2020.

The 11 full papers and 6 short papers presented in this volume were carefully reviewed and selected from 62 submissions. They were organized in topical sections named: mental health; medical record processing; medical information systems; medical diagnosis with machine learning; and health behavior and medication.

<b>Mental Health</b><b>.-</b> Making sense of violence risk predictions using clinical notes

An Auto Question Answering System for Tree Hole Rescue
Research on the Behavior Pattern of Microblog "Tree Hole" Users with Their Temporal Characteristics
Exploring New Opportunities for Mental Healthcare Through the Internet of Things (IoT<b>)</b><b>
</b><b>Medical Record Processing</b><b>
</b>Ontology-based Semantic Similarity Approach for Biomedical Dataset Retrieval
Research on Named Entity Recognition of Traditional Chinese Medicine Electronic Medical Records
AHIAP: An Agile Medical Named Entity Recognition and Relation Extraction Framework Based on Active Learning
<b>Medical Information System</b><b>
</b>An Integrated Knowledge Graph for Microbes-Diseases Associations
A Novel Blockchain based Smart Contract System for eReferral in Healthcare: HealthChain
Telemedicine System with Elements of Artificial Intelligence for Health Monitoring during COVID-19 Pandemic
Genetic Interpretation System for Screening Monogenic Disorders Carriers
<b>Medical Diagnosis with Machine Learning</b><b>
</b>A Prediction Model of Gestational Diabetes Mellitus Based on First Pregnancy Test Index
Antisocial Behaviour Analyses using Deep Learning
A DNN for Arrhythmia Prediction Based on ECG
<b>Health Behavior and Medication</b><b>
</b>An agent based framework for persuasive health behavior change intervention
Design Tailored Nutrition and Weight Control Recommendations Using Nutrigenetics and FFQ
Individualized Medication Guidance based on Pharmacogenomics.