| Methods |
Design: three group parallel trial
Purpose: study the effect of house dust mite impermeable mattress covers on the development of respiratory symptoms, atopic eczema, and mite‐sensitization in children born to mothers with allergy |
| Participants |
Patients: pregnant women in third trimester with allergy
Baseline comparability: yes (several factors), no for gender of children |
| Interventions |
Placebo: house dust mite permeable mattress (cotton) covers
Untreated: no mattress covers
Experimental: house dust mite impermeable mattress (polyester‐cotton) covers
(Co‐intervention: NS) |
| Outcomes |
Wheezing at least once
Recurrent wheezing
Night cough without a cold
Runny nose without a cold
Atopic dermatitis
House dust mite allergen level on bed
Total IgE
House dust mite specific IgE |
| Notes |
|
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Adequate sequence generation? |
Unclear risk |
NS |
| Allocation concealment? |
Unclear risk |
NS |
| Blinding?
Treatment provider |
Low risk |
'...participants were randomly allocated... in a double blind fashion' |
| Blinding?
Outcome assessor |
Unclear risk |
Not relevant as patient reported outcome |
| Incomplete outcome data addressed?
All outcomes |
Low risk |
Drop‐out < 15% |
| Free of selective reporting? |
Unclear risk |
No protocol available |
| Free of other bias? |
Low risk |
|
| No signs of variance inequality or skewness? |
Unclear risk |
Not relevant (binary outcome) |
| Trial size > 49? |
Low risk |
N = 695 |
| Clearly concealed allocation + trial size > 49 + drop‐out max 15% |
High risk |
Allocation not clearly concealed |
