Carpenter 2015.

Study characteristics
Methods	Design: open‐label parallel‐group randomised controlled trial Duration: 1 month Setting: 2 paediatric practices in a medium‐sized metropolitan county in North Carolina, USA Trial registration: NCT01641211
Participants	Population: 91 children and adolescents with asthma randomised to inhaler technique video (n = 46) or an attention control video (n = 45) Age: mean age (SD) in the intervention group was 10.9 (2.6) years, and in the control group 10.8 (2.9) years Baseline asthma severity: intervention group: mild persistent asthma = 52% moderate/severe asthma = 44%; control group: mild persistent asthma = 49% moderate/severe asthma = 51% Inclusion criteria: 7 to 17 years old, could speak English or Spanish, could read the assent form, were present at the visit with an adult (> 18 years old) caregiver (parent or legal guardian) who could speak English or Spanish, used an MDI, missed or incorrectly performed at least 1 step on an inhaler technique assessment, had mild, moderate or severe persistent asthma Exclusion criteria: not reported Percentage withdrawn: 7% of children withdrew from the intervention arm, and 13% from the control arm Other allowed medication: not reported
Interventions	Intervention summary: 3‐minute video in English or Spanish. Separate videos were available for an MDI with or without a spacer; children who indicated that they had used an MDI with a spacer and without a spacer watched both MDI videos. Each inhaler video provided an overview of the device and specific instructions for how to use the device correctly. Children watched the videos on a laptop computer and were given a wallet card with a web address and login information, so they could watch the video again after leaving the clinic Control summary: control group: children allocated to an attention control group in which they watched a 3‐minute video about nutrition in English or Spanish. The nutrition video discussed the importance of balancing protein, carbohydrates and lipids in one’s diet
Outcomes	Outcomes measured: inhaler technique, child inhaler self‐efficacy, asthma control (ACT) Technique assessment method used: MDI technique was measured as the number of steps (out of 8 possible steps) that the child performed correctly. The RA used an inhaler technique checklist to document whether each step was performed correctly
Notes	Type of publication: single peer‐reviewed journal article Funding: This pilot project was supported by Award Number ULTR000083 from the National Center for Advancing Translational Sciences. Dr Carpenter’s salary was supported in part by the National Center for Research Resources and the National Center for Advancing Translational Sciences, National Institutes of Health, through Grant KL2TR000084
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	The randomisation sequence was prepared ahead of time by a statistician who used computer‐generated random numbers. Randomisation was stratified by clinic
Allocation concealment (selection bias)	Low risk	Immediately after the child’s medical visit, the RA opened a sequentially numbered, sealed envelope to determine whether the child had been allocated to the experimental or control group
Blinding of participants and personnel (performance bias) All outcomes	High risk	The study RA was not blinded to children’s experimental group assignment. All children and caregivers were informed that the study was about how children use their asthma devices
Blinding of outcome assessment (detection bias) All outcomes	High risk	The study RA was not blinded to children’s experimental group assignment. All children and caregivers were informed that the study was about how children use their asthma devices
Incomplete outcome data (attrition bias) All outcomes	Low risk	Less than 15% of participants were lost to follow‐up. All randomised participants were included in the adjusted intention‐to‐treat primary analysis
Selective reporting (reporting bias)	Low risk	The study was prospectively registered as NCT01641211; outcomes were reported as planned at all time points
Other bias	Low risk	None noted