These are the MOST ACCURATE method of measuring adherence because they record the date and time the medication bottle was OPENED THROUGH MICROPROCESSOR technology embedded in the cap. (GIVE THE disadvantages of this)

Medication Event Monitoring Systems (MEMS) Disadvantages: 1 erroneous/not faith/falls., because pt may remove more than one dose 2 Very expensive & different devices are needed for each medication 3 Therefore it is an impractical way to determine adherence in clinical practice.