Table 1.

A comprehensive overview of the identified potential barriers for use of the home monitoring system (wireless and real-time), experiences from the pilot study, and possible solutions as suggested by patients and staff

Potential barriers for the use of real-time home spirometry	Findings in our pilot experiment	Possible solutions
No internet access	Patient who never used internet before had no problems using the tablet and perform spirometry because of the simple design.	- Provide patients with a smartphone or tablet with 4G SIM card during study to guarantee internet access - Use a simple application without too much information
Quality of measurements is difficult to control	All patients performed mostly good quality flow volume loops, which could be checked real-time.	- New wireless spirometers have automated quality control and provide advice to patients - Use a device that shows a flow volume loop accessible to patient and researchers to review quality
A handheld spirometer may be difficult to use	A few patients had to get used to handheld spirometry the first days. Only one patient had variable results, due to technical difficulties with the standard mouthpiece. After providing an additional mouthpiece the readings were comparable to hospital readings.	- Provide a clear instruction manual and good training at start of the study. Patients should be able to perform 3 good quality measurements with ≤150 ml difference in the 2 highest FVC’s. - Assess individual patients’ needs - Consider using an extra/other mouthpiece - Use a video consultation or clinic visit for refreshment training
Motivation	A 6 s countdown and FVC target value is always shown during a forced expiration. This motivated patients to blow as good and long as possible.	- Do not use an FVC of 100% predicted as target value as this might demotivate patients - Provide an individual target value for each patient and adjust target value during study if necessary
Home spirometry might induce coughing	Some patients mentioned more urge to cough compared to hospital spirometry, but one measurement a day was not a problem at all.	- Advise patients to perform spirometry after a period of rest - Advise patients to try again later that day when a measurement failed because of coughing
Patients might get worried seeing their own results	Anxiety and depression scores were not higher after this short pilot. Almost all patients considered it pleasant to see their daily results.	- Incorporate automated email alerts to the researchers and explain to patients that they will be contacted if FVC declines significantly - Provide an extra option that blinds patients from their results
Daily home spirometry can be bothersome to patients	None of the patients in the pilot considered once daily spirometry bothersome, because it was not time consuming and became part of their routine.	- Advise patients to perform spirometry at almost the same time every day to create a routine - Explain that the whole process takes less than two minutes
Compliance	Patients got motivated by keeping track of their own results and almost all patients continued home spirometry after the pilot.	- Send patients email reminders when they do not perform spirometry or report their symptoms