Eick 2011.

Methods	Controlled before‐after study
Participants	Children (n = 46), mean age 6.6 years. The homes where at least 1 asthmatic child under 12 years lived permanently and which received income‐related, state‐funded benefits were included and the control homes were randomly chosen from these
Interventions	Retrofitted, whole‐house mechanical ventilation with heat recovery system, laminate flooring, anti‐allergy bed clothes, a central vacuum cleaner and central heating were installed
Outcomes	Buildings, temperature, relative humidity, fine particles, coarse particles, wall/wall surface moisture, dust mite allergen, microbial colonies, carbon dioxide, carbon monoxide Participants: asthma‐related and other respiratory symptoms
Notes	Mould or mould damage was observed in 55% of the homes before intervention. Only the pilot study was included in the review
Risk of bias
Bias	Authors' judgement	Support for judgement
Blinding of participants and personnel (performance bias) All outcomes	High risk	Not blinded
Blinding of outcome assessment (detection bias) All outcomes	High risk	Not blinded
Unplanned subgroup analyses (16)	Low risk	No data dredging
Follow‐up (17)	Low risk	Follow‐up time up to 3 years?
Compliance (19)	Unclear risk	Compliance not reported
Valid outcome measures (20)	Unclear risk	Questionnaire of subjective symptoms
Selection bias (population) (21)	Low risk	Participants and controls were recruited from the same population
Selection bias (time) (22)	Unclear risk	Interviews of the study group and control group were probably performed at the same time
Random sequence generation (selection bias)	High risk	Not done
Allocation concealment (selection bias)	High risk	Not done
Adjustment for confounding (25)	High risk	Not done
Incomplete outcome data (26) (attrition bias)	High risk	Medians of symptom scores were reported in each intervention group