RRR
Abbreviation with 4 meanings
| Stands for | Regular rate and rhythm |
|---|---|
| Meanings | 4 |
| Categories | Medical, Business & Finance, Writing & Everyday |
RRR has four meanings. The most common are Regular rate and rhythm (cardiology) and Relative risk reduction (medical research); it can also stand for Required rate of return and Return receipt requested.
Meanings of RRR at a glance
| # | RRR stands for | Context |
|---|---|---|
| 1 | Regular rate and rhythm | Medical › Cardiology |
| 2 | Relative risk reduction | Medical › Medical Research |
| 3 | Required rate of return | Business & Finance › Finance |
| 4 | Return receipt requested | Writing & Everyday › Mail and Postal |
1. Regular rate and rhythm
Medical · Cardiology Abbreviations
Cardiac exam phrase meaning the heart rate is within the normal range and the beats are evenly spaced, written as part of a normal cardiovascular examination. It appears in nearly every physical exam template in US hospitals and clinics.
Example: CV: RRR, normal S1 and S2, no murmurs, rubs or gallops.
Usually followed by "no MRG" or "no m/r/g." Atrial fibrillation with a controlled rate is documented as "irregularly irregular" instead. In statistics and epidemiology RRR means relative risk reduction, a common source of confusion when reading research summaries alongside clinical notes.
2. Relative risk reduction
Medical · Medical Research Abbreviations
Proportion by which a treatment lowers risk relative to the control group, calculated as the absolute risk reduction divided by the control event rate, or 1 minus the relative risk. A drop from 10 percent to 8 percent is a 20 percent RRR.
Example: Drug ads emphasize a 50% RRR, but the absolute drop was from 2% to 1%.
RRR tends to stay similar across populations while absolute benefit varies with baseline risk, which is why RRR alone can mislead. Studies show patients and clinicians judge treatments more favorably when results are framed in relative rather than absolute terms. In cardiac exam notes RRR means regular rate and rhythm.
3. Required rate of return
Business & Finance · Finance Abbreviations
Minimum annual return an investor or company demands to take on an investment, given its risk and the return available on alternatives. It serves as the discount rate in valuation and the hurdle rate in capital budgeting.
Example: Because the project carries emerging-market risk, the board set an RRR of 14 percent instead of the usual 10.
For equity investors, RRR is often estimated with CAPM; companies evaluating projects commonly start from WACC and adjust for project-specific risk. Also called the hurdle rate. Comparing a project's IRR with its RRR is a standard accept-or-reject test.
4. Return receipt requested
Writing & Everyday · Mail and Postal Abbreviations
Indicates that the sender has asked for proof of delivery bearing the recipient's signature, usually with certified or registered mail. It is printed or stamped on envelopes and noted in legal letters.
Example: Via Certified Mail, RRR, the attorney sent the demand letter to the contractor's business address.
US return receipts can be paper (the green PS Form 3811) or electronic, delivered as a PDF by email. Lawyers note the delivery method above the inside address, as in "VIA CERTIFIED MAIL, RRR." International mail offers a comparable advice-of-delivery service under Universal Postal Union rules.
Related abbreviations
More cardiology abbreviations
- RCM – Restrictive cardiomyopathy
- RFA – Radiofrequency ablation
- RHC – Right heart catheterization
- RHD – Rheumatic heart disease
- RV – Right ventricle
- RVH – Right ventricular hypertrophy
- RVR – Rapid ventricular response
- RVSP – Right ventricular systolic pressure
See all 229 cardiology abbreviations →
More medical research abbreviations
- QoL – Quality of life
- RCT – Randomized controlled trial
- ROC – Receiver operating characteristic
- RR – Relative risk
- RWD – Real-world data
- RWE – Real-world evidence
- SD – Standard deviation
- SDV – Source data verification
See all 94 medical research abbreviations →
This entry is for general education and is not medical advice. Abbreviation use varies between institutions; always confirm in context.