Aj. Apter et al., Testing the reliability of old and new features of a new electronic monitor for metered dose inhalers, ANN ALLER A, 86(4), 2001, pp. 421-424
Background: Poor adherence to treatment regimens is hypothesized to be, in
part, responsible for the extensive morbidity and mortality associated with
asthma. Electronic monitors are the most accurate means available for meas
uring adherence, but their use has been limited by reports questioning the
reliability and validity of their data.
Objective: To test the reliability and accuracy of the MDILog (Medtrac Tech
nologies, Lakewood, CO), a new electronic monitor of metered dose inhalers
(MDIs), and to test its unique features.
Methods: Brief experiments were performed comparing a written diary to the
electronic record using three MDILogs. The following features were studied:
reporting of time and date of an actuation, recording of the occurrence of
an actuation of the MDI, sensing and timing of inhalations, sensing of sha
king of the MDI canister, and recording of multiple actuations.
Results: Clocking was accurate 100% of the time. Actuation agreed with the
paper record 97% to 100%, inhalation 82% to 100%, shaking 86% to 95%. Agree
ment of late inhalations and multiple actuations with paper records was at
least 98%.
Conclusions: The MDILog yields accurate information and is more reliable th
an previously described monitors. Its new features allow more detailed stud
y of how patients use inhalers by allowing evaluation of how patients inhal
e and whether they shake the inhaler canister before use.