As the third quarter of 2014 comes to an end, both Rock Health and StartUp Health have posted reports -- as they always do -- that tracked the amount of funding raked in by digital health companies over the course of the past few months and for the year so far. Rock Health has tracked $3 billion in funding for 2014, while Startup Health has tracked a whopping $5 billion. While both numbers are huge, there's a puzzling $2 billion spread between them.

Rock Health describes its process as a bit more conservative than most as it only includes funding rounds that are more than $2 million, avoids conflating investment dollars with transactional costs associated with M&A, and has a stricter definition of a digital health company than Startup Health does.

Among the top ten investment deals from the quarter that Startup Health highlighted was $230 million that wearable medical device maker Preventice quietly raised last month. According to an SEC filing this transaction was mostly an equity exchange related to the company's merger with eCardio. As part of the deal, the newly merged Preventice apparently raised about $108 million in cash from an accredited investor. 

Similarly, Startup Health counted the $400 million infusion physician practice management company Privia Health secured after merging with an entity set up by a group of investors led by Goldman Sachs. This was, in fact, the biggest digital health investment deal of the year so far, according to Startup Health. Rock Health doesn't usually consider such mergers or rollups to be venture funding, so it doesn't count them in its total.

Startup Health's total figure also includes big rounds from healthcare companies like Oscar ($80 million), which Rock Health categorizes as an insurance company -- not a digital health company -- since it has a license to bear risk as a health insurance carrier. Rock wrote about its process for tracking funding in digital health last year -- it's a helpful read for those trying to make sense of the different figures floating around.

"StartUp Health Insights is the most comprehensive funding database in digital health," a spokesperson told MobiHealthNews in an email. "Their view of what is included in digital health is more broad -- they look at anything that is healthcare and technology enabled. This includes some sectors that others may not automatically constitute as digital health such as genomics."

Both Rock Health's and Startup Health's funding numbers enjoy widespread publication in various media outlets. The data collected by both organizations indicate significant and continuing growth in funding for digital health companies, and for some that trend may be more important than the specifics.

So, if you're interested in the largest figure -- one that likely pushes the bounds of what a digital health company is for most -- it's $5 billion in funding so far in 2014. If you're in need of a more conservative number, that likely leaves out a fair amount of smaller deals, Rock Health's $3 billion is the safer bet.