Burr 1976.

Study characteristics
Methods	Cross‐over trial Randomisation method: not described Not blind Physical
Participants	N = 32 (32 in analyses) Mean age: 33 years Positive skin tests to D pter
Interventions	Test: initial vacuum‐cleaning of the bed and laundering; enclosure of the mattress with a plastic cover for 6 weeks Control: no such interventions
Outcomes	Medication used during the past 24 hours, morning PEFR
Notes	No assessment of mite reduction. Data from Table II
Risk of bias
Bias	Authors' judgement	Support for judgement
Allocation concealment (selection bias)	Unclear risk	Information not available