Comparison Omron M6 Comfort vs A&D UA-604

— Mechanical. A classic design of a blood pressure monitor that many are familiar with includes a shoulder-worn cuff (see "Place of measurement"), a pear for cuff inflation, and a mechanical pressure indicator. This method of measurement requires a phonendoscope, which may be included with the blood pressure monitor or purchased separately. While the procedure is relatively simple, it demands a certain level of skill, and the accuracy of such measurements is considered the lowest among all types of blood pressure monitors. On the positive side, mechanical devices are straightforward in design, cost-effective, do not require a power supply, and can be used in any conditions.

— Automatic. These blood pressure monitors are the most user-friendly: users simply need to place the cuff on the upper arm or wrist (see "Place of measurement") and press a button. The device autonomously handles cuff compression for measurements and displays the results on the screen. Automatic blood pressure monitors can come with various additional functions (see "Features") and are regarded as the most accurate. However, they necessitate mains or battery power and are more expensive compared to other types.

— Semi-automatic. These blood pressure monitors serve as a "transitional option" between mechanical and automatic devices. They employ electronic sensors for measurements similar...to automatic ones, but the cuff is manually inflated using a pear. This design enables the inclusion of additional functions typically found in automatic blood pressure monitors at a considerably lower cost. However, they do require a power supply (although they are more energy-efficient than automatic ones due to the absence of a compressor), and their measurement accuracy is lower compared to automatic models.

Type of power source of the blood pressure monitor. Power is required only for automatic and semi-automatic models (see "Type") — mechanical ones work solely due to the muscular strength of the user.

— Batteries. The blood pressure monitor is powered by replaceable batteries that have a standard size — for example, AA. Such devices are autonomous, because they do not require a mains connection, and batteries are purchased without problems and are easy to change, unlike built-in batteries (see below). On the other hand, batteries are usually not included in the package, and you have to buy them regularly, which is associated with corresponding expenses. An alternative is to buy the elements in the form of rechargeable batteries; they are quite expensive, however, having paid once for batteries and a charger, you no longer have to spend money on energy sources. Anyway, all blood pressure monitors with measurement on the wrist (see "Measuring place"), as well as some models of "shoulder" models, are powered by batteries.

— Batteries/mains. These blood pressure monitors offer dual power options, allowing them to operate on both replaceable batteries and a 230 V network. This versatility enables battery usage in remote locations and the convenience of plugging into the network in more conventional settings to conserve battery life. However, the use of the net...work requires a power source and adds bulk to the complete set. As a result, this type of power supply is exclusive to blood pressure monitors with measurements on the upper arm.

— Battery. These blood pressure monitors are powered by a proprietary, non-standard battery that is often non-removable. Similar to standard batteries, these power sources provide autonomy, allowing the device to function without nearby outlets. However, recharging the exhausted battery requires an electric source, typically an outlet, and the process is time-consuming. As a result, this power supply type is not widely adopted in blood pressure monitors and is primarily found in compact models where the use of standard batteries is technically impractical.

The type of batteries used in blood pressure monitors.

— AA. One of the most common types of batteries today. Voltage — 1.5 V. One of the main advantages of this type of power supply is availability: AA batteries are sold almost everywhere where any batteries are sold at all.

— AAA. A kind of reduced analogue of AA batteries (see above) with the same operating voltage of 1.5 V. AAA batteries are also very common, and the dimensions allow them to be used in more compact devices.

The effective measurement range of a blood pressure monitor covers both "upper" and "lower" pressure values. Most modern devices have a lower limit within 0-20 mm Hg, which is adequate for the majority of cases. As for the upper limit, a device with a maximum value of 180 mm Hg is generally sufficient for individuals without a history of significant blood pressure spikes until old age or without serious illnesses. However, for those prone to substantial increases, it's advisable to consider devices with higher upper limit values, which can reach up to 280 mm Hg in modern blood pressure monitors.

The blood pressure monitor's pulse rate measurement capability typically falls within a range of 30-40 to 180 beats per minute. While extending the lower limit is unnecessary for household blood pressure monitors, a higher upper limit may be essential for measurements during intense physical activity or for individuals with conditions causing significant heart rate acceleration, such as tachycardia.

The cuff's applicable range includes both the minimum and maximum circumferences of the upper arm or wrist (see "Place of measurement"). Modern blood pressure monitors typically feature cuffs suitable for individuals with average physique, covering the majority of adult patients. However, for specialized cases, such as monitoring a child or someone with a larger bicep circumference, it is advisable to measure the arm circumference and compare it with the specified cuff sizes.

— Small. The small cuffs are designed for a shoulder girth of 17-22 cm.

— Standard. Standard cuffs cover a shoulder girth of 22-32 cm.

— Oversized. Oversized cuffs have a girth of 22-36 cm.

— Universal. Cuffs for both thin and large people. Universal cuffs provide a shoulder girth of 22-42 cm.

— Large. Large cuffs with a girth of 33-46 cm are suitable for a full arm or a muscular shoulder of a conditional bodybuilder.

The number of users that can be stored in the device's memory.

Blood pressure moitors with such capabilities are capable of at least storing data for several measurements for each user, which makes it possible not to get confused in the readings if several people use the device. At the same time, a guest mode is also provided so that the measurement made is not wedged into your list.

The number of results that can be simultaneously stored in the blood pressure monitor's memory. The ability to store several results in memory can be useful, for example, to compare pressure readings in the morning, afternoon and evening — these results do not have to be manually recorded or memorized.

— Pulse measurement. The ability to use a blood pressure monitor to measure heart rate (pulse). This frequency, along with blood pressure, is one of the most important indicators of the state of the cardiovascular system.

— Determination of arrhythmia. Blood pressure monitors with this feature are able to track irregularities in the heartbeat (arrhythmia) — one of the important signals of health problems — and warn the user about it.

— Medium pressure calculation. This function allows you to automatically calculate the average pressure based on several consecutive measurements.

— Signal about measurement errors. Blood pressure monitors with this function are able to display error signals that can affect the accuracy of measurements — such as incorrect cuff application, air leakage from it, movement during measurement, device electronics failure, etc.

— Auto switch-off. Most semi-automatic and automatic models of blood pressure monitors are able to automatically turn off after a few minutes of inactivity. This saves battery power.

— Synchronization with PC. In this case, a wired connection is implied, not Bluetooth. Synchronization of the blood pressure monitor with a PC allows you to track...all the measurement results in one table (in some models — even with the date and time), save the results to the PC, freeing up the device's memory, select measurements for calculating the average pressure, etc.

— Bluetooth. The presence of wireless data transfer technology allows you to use the features described in the paragraph "Synchronization with a PC" by connecting to a smartphone and using a special application. This method is more mobile, easier and faster.

— Voicing the measurements. Such blood pressure monitors are able not only to display the measurement results on the screen, but also to voice them, which can be very useful for elderly people with poor eyesight.

— Date and time indication. Having the ability to display the current date and time is useful for recording blood pressure measurements and tracking them over time. Blood pressure monitors equipped with a clock and calendar feature can automatically store measured pressure results in memory, associating them with specific date and time stamps when there is a recording mode.

— WHO colour scale. The World Health Organization has established standards defining normal, low, or elevated blood pressure values. These standards incorporate a color scale that, after each measurement, aids in assessing the pressure status and determining appropriate actions. It's important to note that individual variations exist, and what constitutes normal pressure differs for each person. Therefore, these standards are generally advisory, providing guidance rather than prescribing specific actions.