A study of medication-taking and unobtrusive, intelligent reminding.

Poor medication adherence is one of the major causes of illness and of treatment failure in the United States. The objective of this study was to conduct an initial evaluation of a context-aware reminder system, which generated reminders at an opportune time to take the medication. Ten participants aged 65 or older, living alone and managing their own medications, participated in the study. Participants took a low-dose vitamin C tablet twice daily at times that they specified. Participants were considered adherent if they took the vitamin within 90 minutes (before or after) of the prescribed time. Adherence and activity in the home was measured using a system of sensors, including an instrumented pillbox. There were three phases of the study: baseline, in which there was no prompting; time-based, in which there was prompting at the prescribed times for pill-taking; and context-aware, in which participants were only prompted if they forgot to take their pills and were likely able to take their pills. The context-based prompting resulted in significantly better adherence (92.3%) as compared to time-based (73.5%) or no prompting (68.1%) conditions (p < 0.0002, chi(2) = 17.0). In addition, subjects had better adherence in the morning than in the evening. We have shown in this study that a system that generates reminders at an opportune time to take the medication significantly improves adherence. This study indicates that context-aware prompting may provide improved adherence over standard time-based reminders.

Enabling affordable and efficiently deployed location based smart home systems.

With the obvious eldercare capabilities of smart environments it is a question of "when", rather than "if", these technologies will be routinely integrated into the design of future houses. In the meantime, health monitoring applications must be integrated into already complete home environments. However, there is significant effort involved in installing the hardware necessary to monitor the movements of an elder throughout an environment. Our work seeks to address the high infrastructure requirements of traditional location-based smart home systems by developing an extremely low infrastructure localisation technique. A study of the most efficient method of obtaining calibration data for an environment is conducted and different mobile devices are compared for localisation accuracy and cost trade-off. It is believed that these developments will contribute towards more efficiently deployed location-based smart home systems.

Single access point localisation for wearable wireless sensors.

Knowledge of a subject's location and motion throughout an environment is of significant use to in-home health monitoring and activity recognition systems. This work develops a method of tracking a subject's location using the radio frequency (RF) signals emanating from wearable wireless sensors. It differs from other RF location tracking work in that it utilises the hardware which would already be deployed in a biomedical monitoring application. This is achieved by combining the RSSI (Received Signal Strength Indicator) and LQI (Link Quality Indicator) readings from a single basestation. It is shown that accuracy approaching that of a multiple basestation localisation deployment is achievable by using a suitable level of filtering. As a result of this work, location information can be more readily and cheaply incorporated into future biomedical monitoring applications.

The deployment of a non-intrusive alternative to sleep/wake wrist actigraphy in a home-based study of the elderly.

This paper reports on experimental trials with an Under Mattress Bed Sensor (UMBS), an easily deployable, non-contact, low cost alternative to the actigraphy watch for sleep monitoring. Results from a home-based study of elderly subjects confirm accurate temporal resolution of activity monitoring in bed. UMBS activity classification thresholds were determined by maximizing Matthew's Correlation Coefficient between the activity data captured using an actigraphy watch and the proposed sensor. Preliminary results on a healthy young subject showed very high agreement rates justifying its use as a replacement for wrist actigraphy.

Evaluation of Bluetooth communications for the deployment of assisted living technologies in home environments.

Using five different commercially available class one and class two Bluetooth dongles a total of seven homes which represented a cross section of typical Irish homes were surveyed to determine the effect of construction methods, house size, sensor placement, host placement, antenna design and RF interference had on the link quality of Bluetooth enabled sensors. The results obtained indicates there is high variability in the link quality which is determined by the quality of the BT radio, placement of the antenna on both the master and slave, the number of walls which must be penetrated and the construction materials used in the wall. The placement of the sensor was the single biggest factor in determining the link quality. The type of construction used in the interior walls has significant influence also. The final factor of significant influence was the type of antenna used on the Bluetooth dongle. The use of an external antenna gave significantly better range performance than an internal antenna.