Why is the winner the best?

TL;DR

This study analyzes 80 biomedical image analysis competitions to identify common strategies and characteristics of winning solutions, providing insights to improve future algorithm development and scientific progress.

Contribution

It offers a comprehensive analysis of successful participation strategies and characteristics in biomedical image analysis competitions, highlighting key factors behind winning solutions.

Findings

Winning solutions often use multi-task learning and multi-stage pipelines.

Focus on augmentation, preprocessing, data curation, and postprocessing is common among winners.

Many top algorithms exceed the state of the art, but few fully solve the domain problems.

Abstract

International benchmarking competitions have become fundamental for the comparative performance assessment of image analysis methods. However, little attention has been given to investigating what can be learnt from these competitions. Do they really generate scientific progress? What are common and successful participation strategies? What makes a solution superior to a competing method? To address this gap in the literature, we performed a multi-center study with all 80 competitions that were conducted in the scope of IEEE ISBI 2021 and MICCAI 2021. Statistical analyses performed based on comprehensive descriptions of the submitted algorithms linked to their rank as well as the underlying participation strategies revealed common characteristics of winning solutions. These typically include the use of multi-task learning (63%) and/or multi-stage pipelines (61%), and a focus on augmentation (100%), image preprocessing (97%), data curation (79%), and postprocessing (66%). The "typical" lead of a winning team is a computer scientist with a doctoral degree, five years of experience in biomedical image analysis, and four years of experience in deep learning. Two core general development strategies stood out for highly-ranked teams: the reflection of the metrics in the method design and the focus on analyzing and handling failure cases. According to the organizers, 43% of the winning algorithms exceeded the state of the art but only 11% completely solved the respective domain problem. The insights of our study could help researchers (1) improve algorithm development strategies when approaching new problems, and (2) focus on open research questions revealed by this work.