1	placebo
2	clinical trials
3	SU clinical trials
4	SU randomized controlled trial
5	random allocation
6	single blind
7	random*
8	double blind
9	controlled clinical trial
10	S1 OR S2 OR S3 OR S4 OR S5 OR S6 OR S7 OR S8 OR S9
11	DE "BACKACHE" or DE "SCIATICA" or DE "LUMBAR vertebrae" or DE "LUMBOSACRAL region"
12	back pain
13	backache or sciatica or dorsalgia or lumbago
14	lumb* pain
15	S11 OR S12 OR S13 OR S14
16	S10 AND S15
17	DE "EXERCISE" or DE "BACK exercises" or DE "EXERCISE therapy" or DE "PHYSICAL education & training" or DE "PHYSICAL fitness"
18	exercise
19	pilates or yoga
20	DE "PILATES method"
21	DE "YOGA"
22	McKenzie or Alexander or William or Feldenkrais
23	DE "TAI chi"
24	Tai Chi or Tai Ji or Taiji or Taijiquan
25	S17 OR S18 OR S19 OR S20 OR S21 OR S22 OR S23 OR S24
26	S16 AND S25
27	SU Alexander Disease
28	SU Williams syndrome
29	SU "alexander disease" or "williams syndrome"
30	"alexander disease" or "williams syndrome"
31	S27 OR S28 OR S29 OR S30
32	S26 NOT S31