Ann: Ten US university hospitals now deploying IDTF platform, page-53

I believe the charge (and the reimbursement thereafter) is on each patient for each monitoring period (based on what modality as also indicated in this Anns - "GMV receives ~US$175 to ~US$750 in reimbursements per patient monitored depending on specific modality").
Below is an excerpt from and old DIGIRAD CORPORATION (they sold Telerhythmics to GMV) annual report to US stock exchange SEC regarding Telerhythmics' business operating modality:
(https://www.sec.gov/Archives/edgar/data/707388/000070738817000007/digirad10k2016.htm)

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"

Cardiac Event Monitoring Services

We also offer within Diagnostic Services remote cardiac event monitoring services through our Telerhythmics business. These services include provision of a monitor, remote monitoring by registered nurses, and 24 hours a day, 7 days a week monitoring support for our patients and physician customers. We offer modalities of mobile cardiac telemetry ("MCT"), mobile cardiac event monitoring (both in wireless and analog versions), holter monitoring, and pacemaker analysis. Providing these services offers flexibility and convenience to our customers who do not have to incur the costs of staffing, equipment, and logistics to monitor patients as part of their standard of care.

Our monitoring service operates out of a centralized monitoring center located near Memphis, Tennessee. From this location, the majority of monitoring equipment is shipped directly to patient homes once they are enrolled in our service. Patients hook up the equipment with easy to follow instructions, as well as assistance from our monitoring center. Once they are hooked up to the monitoring device, patients are monitored for a period of time ranging from 7 to 30 days. At the conclusion of the monitoring period, the equipment is packaged up and sent back to our monitoring center, after which the equipment is redeployed to the next patient.

Our cardiac event monitoring services are provided primarily through an independent diagnostic testing facility model that allows us to bill Medicare, Medicaid, or one of the third-party healthcare insurers directly for services provided, and is the only business at Digirad that bills Medicare, Medicaid, and private insurance directly. As such, our cardiac event monitoring services are directly subject to reimbursements from these entities which are subject to change on a periodic basis. Typically, our contracts can be canceled at any time, and are generally present to create understanding on billing responsibilities.

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So from my understanding, if they say monthly revenue, it mostly probably means how much are charged based on total monitored periods (maximum 30 days/a month depending on individual modality, can also be cancelled at anytime hence adding complexity of trying to calculate revenue based on per person). And if one patient is monitored for 1 month then that's easy and it will be counted as one patient only against that month's total patients; but if one patient is monitored 4 recurrent weeks that month (say due to physician's recommendation) then the total number of monitored patients that month is probably not as important as the number of total monitored periods that same month unless that same patient will be counted in as 4 in monthly patient number data (for indicative purpose). In the end IMO what matters (from revenue perspective) is the total number of monitored periods/modalities that the IDTFs conducted at the end of the year (to calculate total revenue). The total number of patients IMO is a (good) indicative figure but not necessarily accurate for estimating total revenue as there are revisited patients (and each patient may have different monitoring modality). IMO only and apology for my loose wording if any.