The Rainbow Study - the Effect of Feedback on Asthmatic Symptom Perception

Asthma is a common childhood disease that is characterized by chronic airway inflammation and episodic expiratory airflow obstruction. Asthma symptoms can impair participation in play and sports and have a negative impact on quality of life. It can be challenging for children to adequately feel and report their symptoms. Some children experience more symptoms than expected based on lung function during these symptoms, whereas others experience less symptoms than expected. This is also called 'symptom perception'.

A tool was developed to visualize symptoms, lung function and accessory symptom perception: The Rainbow tool. The Rainbow tool is a two-dimensional color-coded plot, visualizing the relationship between lung function, denoted as a percentage of personal best (FEV1) on the vertical axis, and VAS score on the horizontal axis. The FEV1 as a percentage of personal best on the vertical axis ranges from 30% to 100% since a maximal VAS score would be expected with a change in FEV1 to ≤ 30% of personal best. The horizontal axis ranges from 0 to 10, with 0 indicating no dyspnea and 10 maximal dyspnea. There are four color-coded zones: the green zone, yellow zone, orange zone, and red zone. The green zone indicates good alignment between symptoms and lung function, and thus a good symptom perception. It forms a diagonal band from the upper left (around 100% FEV1 and VAS score of 0) stretching to the lower right (around 30% FEV1 and VAS score of 10). The green zone is followed by the yellow, orange, and red zones on either side, indicating an increasing deviation in symptom perception from the ideal and respectively mild, moderate, and severe disconcordance between FEV1 and VAS score. The aim of this study was to identify asthmatic children with a poor perception and investigate if their symptom perception could be improved by regular lung function measurements and personal feedback based on the Rainbow Tool.

Hypothesis: Measuring lung function en symptoms and provide personal feedback on perception based on the Rainbow tool has a positive effect on perception of asthma-related symptoms in asthmatic children.

Inclusion criteria

Selection phase:

• Pediatrician diagnosed asthma
• Health care professional thinks perception might be poor
• Age 7 until 15 years old
• Adequate understanding of Dutch language

Intervention phase:

• Adequate number of lung function measurements + VAS scores during selection phase, defined as:
• At least 4 measurements after exercise or when experiencing symptoms and
• At least 2 standard measurements
• Poor perception during selection phase, defined as:
• At least 1 measurement in red zone on Perception Rainbow and/or
• At least 2 measurements in orange zone on Perception Rainbow and/or
• Average of all measurements after exercise or when experiencing symptoms in yellow zone (or orange/red)and/or
• Average of all measurements in yellow zone (or orange/red)

Exclusion criteria

• Severe comorbidity (for example psychomotor retardation or severe cardiopulmonary conditions)
• Not able to fill in VAS score (for example due to blindness)
• Not able to perform technically correct spirometry manoeuvres
• Medication change in past 2 weeks
• Exacerbation which required oral prednisone in the past 6 weeks
• Exacerbation at the moment of inclusion
• No device (computer, tablet or smartphone) with internet connection available at home