Willems 2008.

Methods	Study design: 12‐month parallel RCT Setting: single outpatient centre in the Netherlands
Participants	Population: 109 outpatients (56 children and 53 adults) were randomised to home telemonitoring (55) or to control (54) Baseline characteristics Mean age (SD): monitoring 27.2 (19.3); control 28.4 (21.0) % male: monitoring 58.2; control 44.4 Inclusion criteria: asthmatic outpatients from the Medical Respiratory Department and the Department of Paediatrics. Patients aged 7 and older with an asthma severity of stage I to III as described in the Global Initiative for Asthma (GINA) guidelines were potentially eligible. Patients had to be competent to use an asthma monitor, and had to possess a household phone connection Exclusion criteria: severe co‐morbidity (such as chronic obstructive pulmonary disease or heart failure), structural defects in the upper airways or lungs
Interventions	Intervention: The intervention group used a hand‐held electronic asthma monitor connected to the home modem, which registered lung function and symptoms. Participants were asked to perform daily PEF measurements and to transfer monitor data monthly or more frequently if symptoms worsened. The asthma nurse classified the asthma following a stepwise intervention protocol based on GINA and the Dutch College of General Practitioners, and guided medication changes, usually over the phone. Caregivers assisted the children in monitor use and in contacts with the asthma nurse Control: regular outpatient care
Outcomes	Primary outcome was asthma‐specific quality of life on the AQLQ or the PAQLQ. Children aged 12 to 18 years were asked to complete the adolescent version of the questionnaire by themselves, and parents or caregivers filled in a proxy version for children aged 7 to 12 years. Secondary outcomes were lung function (PEF and FEV1 at baseline and endpoint), self reported symptoms on a 0 to 3 scale and asthma‐related medical consumption from diaries (medication use, visits or telephone contacts with health professionals and ED visits)
Notes	Funding: Dutch Health Care Insurance Board The paper reported adult and child baseline data separately and together, but reported efficacy data only for both age groups combined. Study authors were not able to provide separate efficacy data for adults and children
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomisation took place on participant level after stratification by age (ages 7 to 18 vs 18 years and older), as regular care differs between these age groups. The asthma nurse used a list of random numbers to allocate participants to 1 of the 2 treatment arms
Allocation concealment (selection bias)	Unclear risk	No details about whether or how allocation was concealed
Blinding of participants and personnel (performance bias) Objective outcomes	Low risk	Participants could not be blinded, and nurse practitioners were not blinded to allocation of participants, as they received monthly transfers of monitor data. It is unlikely that this would have introduced bias for objective outcomes (e.g. number of people having exacerbations)
Blinding of participants and personnel (performance bias) Subjective outcomes	High risk	Subjective outcomes such as quality of life and symptom scales filled in by participants or personnel may have been subject to performance bias
Blinding of outcome assessment (detection bias) All outcomes	High risk	We noted no evidence of outcome assessor blinding
Incomplete outcome data (attrition bias) All outcomes	High risk	109 participants were randomised, 5 were lost to follow‐up. Technical problems occurred, and when data transfer was missed, the nurse practitioner attempted to contact participants by telephone; however this was not possible in 21% of missed data transfers. At baseline, compliance with filling in the questionnaires was 100%, for subsequent measurements response rate was 85% to 92% for questionnaires and 81% to 90% for diaries. 28% of PEF data transfers from adults and 18% from children were missed
Selective reporting (reporting bias)	Low risk	Outcomes stated in the Methods were well reported in the Results, but no trial protocol was available to verify
Other bias	Low risk	None noted