Although there are the obviously benefits for older people using medical devices in their home, there are considerable challenges for older people’s interaction with them.
1. Unfriendly interfaces and complex functions
Older people tend to more sedentary and prone to illness, thus, they are often the targets of home-based technologies. They often find that HUMDs are hard to use, with unfriendly interfaces, which can lead to errors when interacting with them in the home environment. As an example, a patient had been using an infusion pump that delivered medication in mL/day. He was given a new pump that administered medication in mL/hour. Having not been trained in the use of the new pump, he programmed it assuming it was the same. And as a result, the patient’s medication was delivered too quickly. Luckily, this patient did recover after the error was noted, but experiences like this can alienate the very users who will benefit the most from the technology.
The myth that older people wish to avoid new functions is largely a fallacy. However, with difficult to use devices can lead to older users becoming disillusioned with functional devices. Older people report frustrations in their interactions with device functions, and they prefer simple products and they frequently use only the relevant functions rather than trying to learn all the functions. As it stands, these technologies are presumably designed with the expectation that anyone should be able to successfully interact with the medical interfaces and functions.
2. Safety and alarm using challenges
Every year many devices fail to warn and alert older people of a fault or error, leading to many safety problems occurring in the home. According to the report of Joint Commission on Accreditation of Health Care Organizations, 65% incidents involving HUMDs were related to alarms. Some observed problems with alarm systems include disabled or incorrectly set alarms; delayed or no response to alarm events; and alarms not being audible in all areas of the patient’s vicinity. Indeed, failure to notice an alarm can in some case lead to serious injury, and in some rate cases death. User errors or incidents will make it more difficult to build confidence and a positive user experience. For example, when an older patient using an infusion pump attached a new cassette for infusion, the patient forgot to remove a cap from the infusion line, which blocked the flow of medication. The pump did not alarm for high pressure, and the patient did not receive medication. This patient was hospitalised as a result. Ideally, users expect HUMDs to easily alert them and at the same time be easy to comprehend.
3. Complicated Instructions and labelling
The FDA have said that even when a device comes with a user manual, instructions are not typically written for a lay user, and as a result, they may not be able to use the device safely and effectively. Some older people have trouble understanding the medical device instructions, particularly with medical jargon such as ‘fulcrum’, ‘systolic’ or ‘diastolic blood pressure’, and they often complain about the complexity of the information. Furthermore, users frequently behave in a way that is inconsistent with what the manufacturers intended; and they may not like to use instruction manuals and try to work out how to use the device themselves using their own intuition. For example, a patient who received a cardiac monitor and electrodes in the mail was instructed by phone how to apply them. She applied the electrodes to her chest, and on activating the device felt a burning sensation on her skin. She informed the instructor over the phone, and he directed her to remove the electrodes and try again with another set of electrodes that had come in the shipment, but they experience the same results. After a few failed attempts at using the device, the patient removed the electrodes from their chest and, in the process, lost some skin and consequently had to go to the emergency room for treatment.
On 17th April 2015, the FDA announced the availability of an Electronic Submission for HUMDs labelling pilot program, running through to December 2015, to provide an opportunity to evaluate the submissions process and system, and usability of the database for the industry. On 14th October 2016, the FDA issued a proposed rule for manufacturers that label Class II and Class III HUMDs to submit device labelling information electronically to the FDA so that patients and health care providers can access this information online.
4. Lack of consideration of older people’s capabilities and prior experience
Ageing brings with it many issues, such as loss of strength and dexterity, which can have a major effect on the way in which people interact with HUMDs. Some HUMDs lack consideration of these enormous changes in older people’s capabilities. For example, a patient doing home nocturnal dialysis was found by her husband, unresponsive. She was disconnected from the dialysis machine, and her tubing was in a closed circuit filled with saline. There was a syringe attached to one of her lines, but the other line was open, and the patient had lost a significant amount of blood. It appeared that she had been unable to clamp her catheter by herself. She died due to blood loss. When older people use medical devices in their homes, reports show that almost 75% of them reported experiencing usage difficulties, such as difficulty seeing or comprehending text and symbols on a device; problems remembering instructions or warnings; or movement control difficulties related to holding or opening a device, which may affect older people’s user experience and their interaction with devices.
Prior experience is one of the main factors influencing the performance of older adults with technology, which is determined by a user’s ability to acquire, store and retrieve relevant information in their long-term memory. Also during the interaction process between older people and HUMDs, prior experience positively affects users’ interaction because they can carry out tasks on a product interface in a more intuitive, faster and less error-prone manner. However, some new home-based medical technologies do not necessarily meet older people’s technology experiences even if they are the target users.
5. Lack of consideration of older people’s limited knowledge and training
Older people tend to have limited knowledge using medical devices in their home. Ideally, they would have training and clear information on how to perform the task with medical devices. However, when this is not the case, they tend to try to solve the problems with their own often limited understanding.
In addition, older users may have difficulty learning to use medical devices at home, especially if the instructions overload the user’s working memory and thus make it difficult to integrate information effectively. On the other hand, some usage related problems are avoidable mistakes owing to the poor design of a product. Although full instructions may come with a device itself, users may make mistakes due to not referring to, or ignoring, the information provided by the manufacturer or the feedback given by a device. Therefore, HUMDs must be compatible with the older people’s typical technological understanding to minimise the number of errors made. This is recognised by the FDA in their design process recommendations, where they say that HUMDs should follow the best practices in devices design to target people with no formal medical training.
All the examples were from the FDA Medical Device Home Use Initiative 2010.