Profile: Karl Holub, Chief Technical Officer

Profile: Karl Holub, Chief Technical Officer
Parvathy Hariharan

The year 2020 has ushered in a new paradigm of medical communication, one that requires more accurate information faster to address the emergence of the novel coronavirus. As a medical data analytics company, Nested Knowledge’s mission has become increasingly relevant throughout the pandemic. We spoke to Karl Holub, Chief Technical Officer at Nested Knowledge, about his vision for the company as a transparent, updatable source for scientific information. A former data scientist at Trip Advisor, Holub became a co-founder of Nested Knowledge, when his friend Kevin Kallmes, now Chief Executive Officer, came to him with the concept of nested data visualizations and a manually-built Excel-spreadsheet-based prototype. “I realized that rigorous data structuring and management are the future of literature reviews,” Holub says. “But it needed a software engineer to build scalability into the product.” After examining existing medical research software, Holub noted that each software provided a solution to only one part of the complex process of meta-analysis. More importantly, none offered a method for growing a structured database across disease states. Holub recognized Nested Knowledge as a feasible method to fill this gap and joined as CTO in March 2019.

In the age of COVID-19, having a source for trusted evidence-based information is critical, Holub says.  He cites the biostatistician John P. A. Ioannidis, who describes the enormous amount of misinformation published during the earliest stages of the coronavirus, with many findings later found to be false, exaggerated or simply not evidence-based. “Nested Knowledge can help with adding structure. Also, tying in reputability of a piece of research is extremely valuable, particularly in times where it’s tempting for researchers to not follow evidence-based practice because everything seems so dire,” Holub says. “If we can then take some of this madness and noise and a bunch of datapoints spread across thousands of studies and consolidate them into recommendations, then it becomes easier for a practitioner to focus and not just follow where the wind blows.”

A “nest” of all data pertaining to COVID-19 is actively being refined by the Nested Knowledge team. Interestingly, the company did not have to build a one-off system for this data and simply modelled it like the other nests built by the company.  “When COVID-19 hit, we did not have to build a brand-new page from scratch,” Holub says. The pandemic drove the team to refine the software further; they came up with the idea for tagging topics in a disease-state-specific hierarchical structure. As an example, Holub cites the hierarchical topics of “intervention”, beneath which is “pharmaceutical intervention”, under which is “antiviral drugs”. The team incorporated this information into a sunburst diagram which made the page more concise, organized and accessible. “Clicking on a single part of the diagram takes you directly to a subset of the literature that you are looking for,” Holub says. “I’d say that COVID-19 brought to the forefront some ways for us to improve the page.”

Holub’s favorite part of his work at Nested Knowledge is the opportunity to explore more features and tools in open-source software and contribute actively to the community.  Another aspect is data-visualization. “It’s been a challenge, since data visualization doesn’t come naturally to me, but it’s also a challenge that I’ve enjoyed immensely working on,” he says. In the future, Holub sees the company integrating with many more platforms, while building generality and scalability regardless of topic, whether a patient is looking for information on knee replacements, heart surgery or infectious diseases. “When you build a webpage that targets non-technical users, you have to refine it quite a bit and then add a lot more guidance than you might think. It’s interesting that in order to make something simpler, you have to do a lot more work.”