Did the Largest Study Ever of the Healing Power of Prayer Show Harm to Cardiac Patients?

The Freedom from Religion Foundation claimed results of the largest RCT of intercessory prayer ever showed that cardiac patients knowing that someone was praying for them had adverse effects.

The Freedom From Religion Foundation article with the claim is here:

Biggest Study: Prayer Harmful to Patients

The Freedom from Religion Foundation (FFRF)

Many of us first became aware of the Freedom from Religion Foundation (FFRF) by way of ads featuring spokesperson Ron Reagan that CNN aired during the CNN/New York Times Tuesday 15 October 2019 Democratic debate. The 30-second ad aired on other cable TV the next day as well. The FFRF said at the time that CBS News had refused to air the ad during the September 2019 Democratic debates and that the other major television networks had refused as well.

The ad had actually been around for five years or more but it had not received much attention until its airing on cable television in October 2019. “Ron Reagan” quickly became the top trending search on Google, beating some of the 20 candidates on stage and upstaging the whole debate.

The ad started with a statement: "Hi, I'm Ron Reagan, an unabashed atheist, and I'm alarmed by the intrusion …