The search strategy gathers together the references from the five potential areas of MEDLINE where they could be found, restricts them to english language publications on human adults and then looks for the study designs meta-analysis, randomised controlled trials, cohort studies and case control studies. In each case the study design is included as a MeSH heading and a text word.
1. exp asthma/
2. exp peak expiratory flow rate/
3. exp lung diseases, obstructive/
4. exp forced expiratory volume/
5.exp dyspnea, paroxysmal/
6.1 or 2 or 3
7.4 not 6
8.5 or 7
9.6 not 8
10.limit 9 to english language
11.limit 10 to human
12.limit 11 to (adult <19 to 44 years> or middle age <45 to 64 years> or aged <65 to 79 years> or "aged, 80 and over")
13.limit 12 to meta analysis
14.exp meta-analysis/
15.12 and 14
16.meta analys:.tw.
17.12 and 16
18.13 or 15 or 17
19.limit 12 to randomized controlled trial
20.random:.tw.
21.12 and 20
22.19 or 21
23.limit 12 to (review or review literature or review of reported cases or review, academic or review, multicase or review, tutorial or scientific integrity review)
24.review.tw.
25.12 and 24
26.23 or 25
27.exp cohort studies/
28.12 and 27
29.cohort.tw.
30.12 and 29
31.28 and 30
32.exp case-control studies/
33.12 and 32
34.case control.tw.
35.12 and 34
36.33 or 35
37.18 or 22 or 26 or 31 or 36