Use of metered-dose inhaler electronic monitoring in a real-world asthma randomized controlled trial

J Allergy Clin Immunol Pract. 2013 Jan;1(1):83-91. doi: 10.1016/j.jaip.2012.08.004. Epub 2012 Nov 2.


Background: Electronic monitoring of inhaled asthma medications is one method to measure medication adherence and patterns of use. Information on the performance of monitors in a randomized controlled trial allows researchers and clinicians to understand their utility and limitations. The Smartinhaler Tracker is an electronic monitor for metered-dose inhalers (MDIs) that records the date, time, and number of actuations.

Objective: To determine the performance of the Smartinhaler monitors used in a 24-week randomized controlled trial of 303 patients with asthma in a real-world setting.

Methods: Prestudy use checks involved 2 actuations of the MDI, with a further 2 performed 2 hours later. Within-study monitor checks, performed before dispensing at clinic visits 2 to 4, included a computerized check of monitor clock function, actuation accuracy, and battery life. Within-study data checks involved computerized checks of monitor clock function before data upload.

Results: Two thousand six hundred seventy-eight of 2728 monitors (98.2%) passed prestudy use checks. Seventy-six of 2642 monitors (2.9%) dispensed to participants failed within-study monitor checks. Fifty-one of 2642 monitors (1.9%) malfunctioned before data upload, mostly as a result of fluid immersion. Ninety-three of 2642 monitors (3.5%) were lost or thrown away by participants. Complete data was available from 2498 of 2642 dispensed monitors (94.5%) and 2498 of 2549 returned monitors (98.0%).

Conclusions: The Smartinhaler Tracker is a reliable monitor for measuring MDI use in a real-world setting. Use of extensive monitor and data-checking protocols reduces data loss. In a research or clinical setting, the use of a validated and reliable electronic monitor represents the reference standard for assessing patterns of medication use.

Keywords: Adherence; Asthma; Electronic; Fixed-dose combination inhaler as maintenance therapy with short-acting beta agonist as reliever; MDI; Metered-dose inhaler; Monitoring; Patterns of use; RCT; Randomized controlled trial; SMART; STANDARD; Single combination inhaler as Maintenance And Reliever Therapy; Smartinhaler; Validation.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Inhalation
  • Adolescent
  • Adult
  • Aged
  • Anti-Asthmatic Agents
  • Asthma / drug therapy*
  • Australia
  • Bronchodilator Agents
  • Female
  • Humans
  • Male
  • Medication Adherence / statistics & numerical data
  • Metered Dose Inhalers / standards*
  • Middle Aged
  • Monitoring, Physiologic / instrumentation*
  • Monitoring, Physiologic / methods
  • Monitoring, Physiologic / statistics & numerical data
  • New Zealand
  • Prospective Studies
  • Young Adult


  • Anti-Asthmatic Agents
  • Bronchodilator Agents