21.   There are few controlled studies of treatment and because of the complex nature of the disorder such studies are difficult to undertake.

22.   Although no adverse effects have been detected in long-term users in Germany, only a long-term controlled clinical study can give the herb a clean bill of health.

23.   As a consequence, we get the best controlled studies.

24.   Because the Konza buffalo are part of a controlled study, they are not fed or cared for during most of the year.

25.   But few significant controlled studies have been done to verify the healing effect of applying magnets to the body.

26.   But he said policy makers were hampered by the lack of data from rigorously controlled scientific studies.

27.   But he said this would be only in the context of a carefully controlled study in which patients are told of the potential harmful effects.

28.   But no one could ever prove such a benefit in a controlled study.

29.   But Terman said the approach must be tested in large controlled studies.

30.   Chiropractic manipulation is commonly used, but rigorously controlled scientific studies are needed to determine its effectiveness, the report said.