The significance of "nonsignificance" in randomized controlled studies: A discussion inspired by a double-blinded study on St. John's Wort (Hypericum perforatum L.) for premenstrual symptoms

Journal of Alternative and Complementary Medicine

Volumn 10, Issue 6, 2004, Pages 925-932

  Hicks, Stephen M ^a   Walker, Ann F ^a   Gallagher, James ^a   Middleton, Richard W ^b   Wright, John ^a  

^a UNIVERSITY OF READING   (United Kingdom)

^b Lichtwer Pharma UK Ltd   (United Kingdom)

Author keywords

[No Author keywords available]

Indexed keywords

HYPERICIN; HYPERICUM PERFORATUM EXTRACT;

ACNE; ANXIETY DISORDER; ARTICLE; BACKACHE; BLOATING; BREAST TENDERNESS; CLINICAL TRIAL; CONFUSION; CONSTIPATION; CONTROLLED CLINICAL TRIAL; CONTROLLED STUDY; CRYING; DEPRESSION; DIARRHEA; DISEASE EXACERBATION; DIZZINESS; DOUBLE BLIND PROCEDURE; DRIVE; DRUG EFFICACY; EDEMA; EYE DISEASE; EYE PAIN; FATIGUE; FEMALE; FLATULENCE; HEADACHE; HEART DISEASE; HUMAN; HYDRATION; INCREASED APPETITE; INSOMNIA; IRRITABILITY; MAJOR CLINICAL STUDY; MEMORY DISORDER; MOOD DISORDER; MYALGIA; NAUSEA; NERVOUSNESS; OUTCOMES RESEARCH; PREMENSTRUAL SYNDROME; PRIORITY JOURNAL; RANDOMIZED CONTROLLED TRIAL; RASH; RECURRENT DISEASE; SYNCOPE; URINARY FREQUENCY; WEIGHT GAIN; WITHDRAWAL SYNDROME; XEROSTOMIA;

ADULT; ANTI-ANXIETY AGENTS; ANTIDEPRESSIVE AGENTS; ANXIETY; DEPRESSION; DOSE-RESPONSE RELATIONSHIP, DRUG; DOUBLE-BLIND METHOD; DRUG ADMINISTRATION SCHEDULE; ENGLAND; FEMALE; HUMANS; HYPERICUM; PHYTOTHERAPY; PLANT EXTRACTS; PREMENSTRUAL SYNDROME; REGRESSION ANALYSIS; TREATMENT OUTCOME;

EID: 13144249127     PISSN: 10755535     EISSN: None     Source Type: Journal    
DOI: 10.1089/acm.2004.10.925     Document Type: Article

References (15)

1. Abraham GE. Nutritional factors in the etiology of the premenstrual tension syndromes. J Reprod Med 1983;28:446-464.
2. Christie S, Walker AF. Vitex agnus-castus L.:(1) A review of its traditional and modern therapeutic use; (2) Current use from a survey of practitioners. Eur J Herbal Med 1997;3:29-45.
3. De Souza MC, Walker AF, Robinson PA, Bolland K. A synergistic effect of a daily supplement for 1 month of 200 mg magnesium plus 50 mg vitamin B6 for the relief of anxiety-related premenstrual symptoms: A randomized, double-blind, crossover study. J Womens Health Gend Based Med 2000;9:131-139.
4. Doll H, Brown S, Thurston A, Vessey M. Pyridoxine (vitamin B6) and the premenstrual syndrome: A randomised crossover trial. J R Coll Gen Pract 1989;39:364-368.
5. Hamilton JA, Parry BA, Alagna S, Blumenthal S, Herz E. Premenstrual mood changes: A guide to evaluation and treatment. Psychiatr Ann 1984;14:406-420.
6. Hansgen KD, Vesper J, Ploch M. Multicenter double-blind study examining the antidepressant effectiveness of the Hypericum Extract LI 160. J Geriatr Psychiatry Neurol 1994;7:S15-S18.
7. Hirschfeld RM. History and evolution of the monoamine hypothesis of depression. J Clin Psychiatry 2000;61(Suppl 6):4-6.
8. Kouri EM, Halbreich U. State and trait serotonergic abnormalities in women with dysphoric premenstrual syndromes. Psychopharmacol Bull 1997;33:767-770.
9. Linde K, Mulrow CD. St John's wort for depression. Cochrane Database Syst Rev 2000;2:CD000448.
10. Lipsey MW. Design Sensitivity: Statistical Power for Experimental Research. Thousand Oaks, CA: Sage Publications, 1990.
11. Moher D, Dulberg CS, Wells GA. Statistical power, sample size, and their reporting in randomised controlled trials. JAMA 1994;272:122-124.
12. Moos RH. Typology of menstrual cycle symptoms. Am J Obstet Gynecol 1969;103:390-402.
13. Rapkin AJ. The role of serotonin in premenstrual syndrome. Clin Obstet Gynecol 1992;35:629-636.
14. Stevinson C, Ernst E. A pilot study of Hypericum perforatum for the treatment of premenstrual syndrome. Br J Obstet Gynecol 2000;107:870-876.
15. Walker AF, De Souza MC, Marakis G, Robinson PA, Morris AP, Bolland KM. Unexpected benefit of sorbitol placebo in Mg intervention study of premenstrual symptoms: implications for choice of placebo in RCTs. Med Hypothesis 2002;58:213-220.