Just a few months ago, the ACC & AHA released a set of four clinical guidelines focused on cardiovascular risk assessment, cholesterol, lifestyle modification, and obesity.

Whatever your opinion of this current set of guidelines, they do represent at least a well-intentioned effort to help promote evidence based practice.

Writing the guideline is only the beginning.

The next, and perhaps more important stage, is driving adoption and implementation. With these guidelines, an important change was the creation of a new 10-year ASCVD risk estimator.

We perused the iOS App Store and Google Play store for apps that incorporated this risk calculator, searching for insights that could help us understand better the role that apps are playing in the implementation of clinical guidelines.

To start, we searched for apps that included the ASCVD calculator in the iOS App Store using the terms cholesterol, ASCVD, and lipid. From these results, we identified a total of six apps focused on the the new 10-year ASCVD risk estimation.

We then looked at the Google Play store for similar apps using the search term ASCVD and pulled information for apps available in both stores.

So what does this tell us?

Apps can be released quickly by a responsive developer community

The ACC/AHA guidelines were released on November 12th. The first app related to these guidelines, specifically the risk estimation component, was released 9 days later. Within about two and a half weeks, there were five choices available.

As an aside, it’s worth noting that two of the most popular calculator apps – QxMD Calculate and MedCalc – do not yet include this risk estimator. One of the developers of MedCalc offers up an interesting reason as to why:


What is interesting is that these apps were from smaller developers i.e. not heavyweights like Epocrates whose CardioTool app does not include this risk estimator. One way to interpret that is as reflective of the low barrier to entry to this market where smaller developers can readily beat bigger, more established developers to the end consumer.

Clinicians want apps from known and trusted sources

However, just being first on the block is not good enough. While it was last on the block by quite a margin, the ACC’s ASCVD risk app appears to be the far and away leader in popularity. In just over a week, it has accumulated what appears to be more downloads than the other apps combined.

There are two explanations worth considering. First, clinicians may have searched for risk estimator apps and not been happy with what they saw–until the ACC app was released. Alternatively, its possible that clinicians were not searching for these apps on their own but were rather directed to the ACC’s app directly from, say, CardioSource.

Based on these findings, there does appear to be significant demand for apps from professional societies and other known, trusted sources. One has to wonder whether users directed from other sources (i.e. links from JACC or Circulation) comparison shopped and genuinely felt the ACC app was the best or whether they just picked the ACC app due to trust and comfort.

What about testing?

Its worth noting that none of the available apps has readily available information on testing prior to release. For better or worse, the results of this estimator could lead reflexively to initiation (or discontinuation) of lipid therapy and so knowing an app or website you’re using is accurate is important.

For calculators based on just a formula or checklist, accuracy checking can be fairly straightforward. However, with estimators like this – where assessment is based on a rather complicated set of tables – the process is more involved. Looking at the version history for the Cardiac Risk Assist app, three of the eight updates list Revise Recommendations, a fairly nebulous term which could imply errors that were corrected (or just spelling mistakes).


Apps offer certain advantages when it comes to disseminating and implementing evidence-based guidelines, of which we can expect to see more. One strength is that they offer a method to get tools to market very quickly. However, it does appear that many clinicians did wait several months for the ACC app – whether that is because they passed on less familiar developers or simply hadn’t looked in the app stores remains to be seen.