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.

Mental Health.- 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).- Medical Record Processing.- 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.- Medical Information System.- 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.- Medical Diagnosis with Machine Learning.- 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.- Health Behavior and Medication.- 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.