mmequiv

The goal of mmequiv is to provide users the ability to calculate standardized Morphine Milligram Equivalent (MME) doses for prescription opioid medications for research purposes.

mmequiv uses information about prescription opioids used by study participants to calculate MME and daily MME based on several standardized definitions, including directly interfacing with the NIH HEAL MME Online Calculator¹ API from R. Because the NIH HEAL MME Online Calculator API has a rate limit of 50 (patient-level) requests per 15 minutes, mmequiv can also perform the same calculations locally without needing to call the API when working with larger data or when internet access is unavailable.

mmequiv is intended for the same purposes as the NIH HEAL MME Online Calculator - as a data resource for: research, analytical purposes using claims or dispensing data, and surveillance of population-level medication utilization.

Important: Users should be aware of the caveats and limitations of the NIH HEAL MME Online Calculator - these also apply to mmequiv:

The data collection tool is NOT intended for any clinical decision-making by clinicians while prescribing opioids. The MME conversion factors in this survey DO NOT constitute any clinical guidance for prescribing or recommendations for converting patients from one form of opioid analgesic to another.

Much of the information in the mmequiv documentation is pulled directly from either the NIH HEAL MME Online Calculator website or the paper from the calculator’s creators.² I recommend reviewing these resources for any details not covered by the package documentation.

Installation

You can install mmequiv from CRAN using the following code:

install.packages("mmequiv")

You can install the development version of mmequiv like so:

# install.packages("remotes")
remotes::install_github('KennethATaylor/mmequiv')

Citation

In addition to citing the original paper by Adams, et al.,³ consider citing this package. You can obtain information needed to cite the package by running:

citation("mmequiv")

Footnotes

1. Find the online version of the calculator at this link; accessible as of May 19, 2025. ↩

2. Adams MCB, Sward KA, Perkins ML, Hurley RW. Standardizing research methods for opioid dose comparison: the NIH HEAL morphine milligram equivalent calculator. PAIN. Published online February 3, 2025. doi: 10.1097/j.pain.0000000000003529 ↩

3. Adams MCB, Sward KA, Perkins ML, Hurley RW. Standardizing research methods for opioid dose comparison: the NIH HEAL morphine milligram equivalent calculator. PAIN. Published online February 3, 2025. doi: 10.1097/j.pain.0000000000003529 ↩