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K Linde

Publications and source records attributed to K Linde.

At least 37 records · Page 2Linked to original sources

Systematic reviews of herbal medicines--an annotated bibliography.

OBJECTIVE: To provide a comprehensive collection and a summary of systematic reviews of clinical trials on herbal medicines. METHODS: Potentially relevant reviews were searched through the register of the Cochrane Complementary Medicine Field, the Cochrane Library, Medline, and bibliographies of articles and books. To be included articles had to review prospective clinical trials of herbal medicines; had to describe review methods explicitly; had to be published; and had to focus on treatment effects. Information on conditions, interventions, methods, results and conclusions was extracted using a pretested form and summarized descriptively. RESULTS: From a total of 79 potentially relevant reviews preselected in the screening process 58 met the inclusion criteria. 30 of the reports reviewed ginkgo (for dementia, intermittent claudication, tinnitus, and macular degeneration), hypericum (for depression) or garlic preparations (for cardiovascular risk factors and lower limb atherosclerosis). The quality of primary studies was criticized in the majority of the reviews. Most reviews judged the available evidence as promising but definitive conclusions were rarely possible. CONCLUSIONS: Systematic reviews are available on a broad range of herbal preparations prescribed for defined conditions. There is very little evidence on the effectiveness of herbalism as practiced by specialist herbalists who combine herbs and use unconventional diagnosis.

Clinical Trials as Topic↗

Acupuncture Randomized Trials (ART) in patients with migraine or tension-type headache--design and protocols.

BACKGROUND AND OBJECTIVE: We report the design and essentials of the protocols of two Acupuncture Randomized Trials (ART) investigating whether acupuncture is more efficacious than no treatment and minimal acupuncture in the interval treatment of migraine and tension-type headache. DESIGN: Randomized controlled multicenter trials with three treatment arms and a total observation period of 28 weeks. SETTING: 30 practitioners and outpatient units in Germany specialized in acupuncture treatment. PATIENTS: Per study 300 patients with migraine and episodic or chronic tension-type headache, respectively (diagnosis according to the criteria of the International Headache Society). INTERVENTIONS: Patients are randomly assigned to receive either (1) semi-standardized acupuncture (150 patients), (2) standardized minimal acupuncture (75 patients), or (3) no interval treatment for 12 weeks followed by semi-standardized acupuncture (75 patients, waiting list control). Acupuncture treatment consists of 12 sessions per patient over a period of 8 weeks. MAIN OUTCOME MEASURE: Main outcome measure in the migraine trial is the difference between the number of days with headache of moderate or severe intensity during the 4 weeks before randomization and weeks 9 to 12 after randomization. In the study on tension-type headache the main outcome measure is similar to that described above, but for the number of headache days regardless of intensity. OUTLOOK: The results of these two studies (available in 2004) will provide health care providers and policy makers with the information needed to make scientifically sound assessments of acupuncture therapy.

Acupuncture Therapy↗

Acupuncture Randomized Trials (ART) in patients with chronic low back pain and osteoarthritis of the knee - design and protocols.

BACKGROUND: We report on the study design and protocols of two randomized controlled trials (Acupuncture Randomized Trials = ART) that investigate the efficacy of acupuncture in the treatment of chronic low back pain and osteoarthritis of the knee, respectively. OBJECTIVE: To investigate whether acupuncture is more efficacious than (a) no treatment or (b) minimal acupuncture in the treatment of low back pain and osteoarthritis. DESIGN: Two randomized, controlled, multicenter trials with three treatment arms and a total follow-up time of 52 weeks. SETTING: 30 practitioners and outpatient units in Germany specialized in acupuncture treatment. PATIENTS: 300 patients will be included in each study. In the low back pain trial, patients will be included according to clinical diagnosis. In the osteoarthritis pain trial, patients will be included according to the American College of Rheumatology criteria. INTERVENTIONS: Patients are randomly assigned to receive either (1) semi-standardized acupuncture (150 patients), (2) minimal acupuncture at non-acupuncture points (75 patients), or (3) no treatment for two months followed by semi-standardized acupuncture (75 patients, waiting list control). Acupuncture treatment consists of 12 sessions per patient over a period of 8 weeks. MAIN OUTCOME MEASURE: The main outcome measure is the difference between baseline and the end of the 8-week treatment period in the following parameters: pain intensity as measured by a visual analogue scale (VAS; 0-100 mm) in the low back pain trial and by the Western Ontario and McMaster Universities Osteoarthritis Score (WOMAC) in the osteoarthritis trial. OUTLOOK: The results of these two studies (available in 2004) will provide health care providers and policy makers with the information needed to make scientifically sound assessments of acupuncture therapy.

Acupuncture Therapy↗

Systematic reviews of complementary therapies - an annotated bibliography. Part 3: homeopathy.

BACKGROUND: Complementary therapies are widespread but controversial. We aim to provide a comprehensive collection and a summary of systematic reviews of clinical trials in three major complementary therapies (acupuncture, herbal medicine, homeopathy). This article is dealing with homeopathy. Potentially relevant reviews were searched through the register of the Cochrane Complementary Medicine Field, the Cochrane Library, Medline, and bibliographies of articles and books. To be included articles had to review prospective clinical trials of homeopathy; had to describe review methods explicitly; had to be published; and had to focus on treatment effects. Information on conditions, interventions, methods, results and conclusions was extracted using a pretested form and summarized descriptively. RESULTS: Eighteen out of 22 potentially relevant reviews preselected in the screening process met the inclusion criteria. Six reviews addressed the question whether homeopathy is effective across conditions and interventions. The majority of available trials seem to report positive results but the evidence is not convincing. For isopathic nosodes for allergic conditions, oscillococcinum for influenza-like syndromes and galphimia for pollinosis the evidence is promising while in other areas reviewed the results are equivocal. INTERPRETATION: Reviews on homeopathy often address general questions. While the evidence is promising for some topics the findings of the available reviews are unlikely to end the controversy on this therapy.

Asthma↗

Systematic reviews of complementary therapies - an annotated bibliography. Part 2: herbal medicine.

BACKGROUND: Complementary therapies are widespread but controversial. We aim to provide a comprehensive collection and a summary of systematic reviews of clinical trials in three major complementary therapies (acupuncture, herbal medicine, homeopathy). This article is dealing with herbal medicine. Potentially relevant reviews were searched through the register of the Cochrane Complementary Medicine Field, the Cochrane Library, Medline, and bibliographies of articles and books. To be included articles had to review prospective clinical trials of herbal medicines; had to describe review methods explicitly; had to be published; and had to focus on treatment effects. Information on conditions, interventions, methods, results and conclusions was extracted using a pre-tested form and summarized descriptively. RESULTS: From a total of 79 potentially relevant reviews pre-selected in the screening process 58 met the inclusion criteria. Thirty of the reports reviewed ginkgo (for dementia, intermittent claudication, tinnitus, and macular degeneration), hypericum (for depression) or garlic preparations (for cardiovascular risk factors and lower limb atherosclerosis). The quality of primary studies was criticized in the majority of the reviews. Most reviews judged the available evidence as promising but definitive conclusions were rarely possible. CONCLUSIONS: Systematic reviews are available on a broad range of herbal preparations prescribed for defined conditions. There is very little evidence on the effectiveness of herbalism as practised by specialist herbalists who combine herbs and use unconventional diagnosis.

Herbal Medicine↗

Systematic reviews of complementary therapies - an annotated bibliography. Part 1: acupuncture.

BACKGROUND: Complementary therapies are widespread but controversial. We aim to provide a comprehensive collection and a summary of systematic reviews of clinical trials in three major complementary therapies (acupuncture, herbal medicine, homeopathy). This article is dealing with acupuncture. Potentially relevant reviews were searched through the register of the Cochrane Complementary Medicine Field, the Cochrane Library, Medline, and bibliographies of articles and books. To be included articles had to review prospective clinical trials of acupuncture; had to describe review methods explicitly; had to be published; and had to focus on treatment effects. Information on conditions, interventions, methods, results and conclusions was extracted using a pretested form and summarized descriptively. RESULTS: From a total of 48 potentially relevant reviews preselected in a screening process 39 met the inclusion criteria. 22 were on various pain syndromes or rheumatic diseases. Other topics addressed by more than one review were addiction, nausea, asthma and tinnitus. Almost unanimously the reviews state that acupuncture trials include too few patients. Often included trials are heterogeneous regarding patients, interventions and outcome measures, are considered to have insufficient quality and contradictory results. Convincing evidence is available only for postoperative nausea, for which acupuncture appears to be of benefit, and smoking cessation, where acupuncture is no more effective than sham acupuncture. CONCLUSIONS: A large number of systematic reviews on acupuncture exists. What is most obvious from these reviews is the need for (the funding of) well-designed, larger clinical trials.

Acupuncture↗

Acupuncture for idiopathic headache.

BACKGROUND: Acupuncture is widely used for the treatment of headache, but its effectiveness is controversial. OBJECTIVES: To determine whether acupuncture is: - more effective than no treatment - more effective than 'sham' (placebo) acupuncture - as effective as other interventions used to treat idiopathic (primary) headaches. SEARCH STRATEGY: Electronic searches were performed in MEDLINE, EMBASE, the Cochrane Controlled Trials Register, and the database of the Cochrane Field for Complementary Medicine. We also contacted researchers in the field and checked the bibliographies of all articles obtained. SELECTION CRITERIA: Randomized or quasi-randomized clinical trials comparing acupuncture with any type of control intervention for the treatment of idiopathic (primary) headaches were included. DATA COLLECTION AND ANALYSIS: Information on patients, interventions, methods, and results was extracted by at least two independent reviewers using a pre-tested standard form. Results on headache frequency and intensity were summarized descriptively. Responder rate ratios (responder rate in treatment group/responder rate in control group) were calculated as a crude indicator of results for sham-acupuncture-controlled trials. Quantitative meta-analysis was not possible due to trial heterogeneity and insufficient reporting. MAIN RESULTS: Twenty-six trials including a total of 1151 patients (median, 37; range, 10-150) met the inclusion criteria. Sixteen trials were conducted among patients with migraine, six among patients with tension-type headache, and four among patients with various types of headaches. The majority of trials had methodological and/or reporting shortcomings. In eight of the 16 trials comparing true and sham (placebo) acupuncture in migraine and tension-type headache patients, true acupuncture was reported to be significantly superior; in four trials there was a trend in favor of true acupuncture; and in two trials there was no difference between the two interventions. (Two trials were uninterpretable.) The 10 trials comparing acupuncture with other forms of treatment yielded contradictory results. REVIEWER'S CONCLUSIONS: Overall, the existing evidence supports the value of acupuncture for the treatment of idiopathic headaches. However, the quality and amount of evidence are not fully convincing. There is an urgent need for well-planned, large-scale studies to assess the effectiveness and cost-effectiveness of acupuncture under real-life conditions.

Acupuncture Therapy↗

The methodological quality of randomized controlled trials of homeopathy, herbal medicines and acupuncture.

BACKGROUND: To investigate the methodological quality of randomized controlled trials in three areas of complementary medicine. METHODS: The methodological quality of 207 randomized trials collected for five previously published systematic reviews on homeopathy, herbal medicine (Hypericum for depression, Echinacea for common cold), and acupuncture (for asthma and chronic headache) was assessed using a validated scale (the Jadad scale) and single quality items. RESULTS: While the methodological quality of the trials was highly variable, the majority had important shortcomings in reporting and/or methodology. Major problems in most trials were the description of allocation concealment and the reporting of drop-outs and withdrawals. There were relevant differences in single quality components between the different complementary therapies: For example, acupuncture trials reported adequate allocation concealment less often (6% versus 32% of homeopathy and 26% of herb trials), and trials on herbal extracts had better summary scores (mean score 3.12 versus 2.33 for homeopathy and 2.19 for acupuncture trials). Larger trials published more recently in journals listed in Medline and in English language scored significantly higher than trials not meeting these criteria. CONCLUSION: Trials of complementary therapies often have relevant methodological weaknesses. The type of weaknesses varies considerably across interventions.

Acupuncture Therapy↗

Acupuncture for chronic asthma.

BACKGROUND: Acupuncture has traditionally been used to treat asthma in China and is used increasingly for this purpose internationally. OBJECTIVES: The objective of this review was to assess the effects of acupuncture for the treatment of asthma or asthma-like symptoms. SEARCH STRATEGY: We searched the Cochrane Airways Group trials register, the Cochrane Complementary Medicine Field trials register and reference lists of articles. SELECTION CRITERIA: Randomised and possibly randomised trials using acupuncture to treat asthma and asthma-like symptoms. Acupuncture could involve the insertion of needles or other forms of stimulation of acupuncture points. DATA COLLECTION AND ANALYSIS: Trial quality was assessed by at least two reviewers independently. A reviewer experienced in acupuncture assessed the adequacy of the sham acupuncture. Study authors were contacted for missing information. MAIN RESULTS: Seven trials involving 174 people were included. Trial quality varied and results were inconsistent. No statistically significant or clinically relevant effects were found for acupuncture compared to sham acupuncture. However the points used in the sham arm of some studies are used for the treatment of asthma according to traditional Chinese medicine. Only one study used individualised treatment strategies. Lung function could be compared statistically in only 3 trials. Peak expiratory flow rate showed a statistically insignificant increase of 8.4 litres/minute weighted mean difference (95% confidence interval -29.4 to 46.2) when acupuncture was compared to sham acupuncture. REVIEWER'S CONCLUSIONS: There is not enough evidence to make recommendations about the value of acupuncture in asthma treatment. Further research needs to consider the complexities and different types of acupuncture.

Acupuncture Therapy↗

Homeopathy for chronic asthma.

BACKGROUND: Homeopathy involves the use, in dilution, of substances which cause symptoms in their undiluted form. It is one of the most widespread forms of complementary medicines and is also used to treat asthma. OBJECTIVES: The objective of this review was to assess the effects of homeopathy in people with chronic stable asthma. SEARCH STRATEGY: We searched the Cochrane Airways Group trials register, the Cochrane Complementary Medicine Field trials register, the Glasgow Homeopathic Hospital database, the Muenchener Modell database and reference lists of articles. SELECTION CRITERIA: Randomised and possibly randomised trials of homeopathy for the treatment of stable chronic asthma, with observation periods of at least one week. DATA COLLECTION AND ANALYSIS: Data extraction was done by one reviewer and checked by the second reviewer. Trial quality was assessed by the reviewers. MAIN RESULTS: Three trials with a total of 154 people were included. These trials were all placebo-controlled and double-blind, but of variable quality. They used three different homeopathic treatments which precluded quantitative pooling of results. The standardised treatments in these trials are unlikely to represent common homeopathic practice, where treatment tends to be individualised. In one trial, severity of symptoms was lessened in the homeopathy group compared to the placebo group. In another trial, lung function measures and medication use showed improvement in the homeopathy group compared to the placebo group. The third trial found improvement in both the homeopathy and placebo groups, but no difference between the groups. REVIEWER'S CONCLUSIONS: There is not enough evidence to reliably assess the possible role of homeopathy in asthma. As well as randomised trials, there is a need for observational data to document the different methods of homeopathic prescribing and how patients respond.

Asthma↗

St John's wort for depression.

BACKGROUND: Extracts of the plant Hypericum perforatum L. (popularly called St. John's wort) have been used in folk medicine for a long time for a range of indications including depressive disorders. OBJECTIVES: To investigate whether extracts of Hypericum are more effective than placebo and as effective as standard antidepressants in the treatment of depressive disorders in adults; and whether they have have less side effects than standard antidepressant drugs. SEARCH STRATEGY: Trials were searched in computerized general (Medline, Embase, Psychlit, Psychindex) and specialized databases (Cochrane Complementary Medicine Field, Cochrane Depression & Neurosis CRG, Phytodok); by checking bibliographies of pertinent articles; and by contacting manufacturers and researchers. SELECTION CRITERIA: Trials were included if they: (1) were randomized; (2) included patients with depressive disorders; (3) compared preparations of St. John's wort (alone or in combination with other plant extracts) with placebo or other antidepressants; and (4) included clinical outcomes such as scales assessing depressive symptoms. DATA COLLECTION AND ANALYSIS: Information on patients, interventions, outcomes and results was extracted by at least two independent reviewers using a standard form. The main outcome measure for comparing the effectiveness of Hypericum with placebo and standard antidepressants was the responder rate ratio (responder rate in treatment group/responder rate in control group). The main outcome measure for side effects was the number of patients reporting side effects. MAIN RESULTS: 27 trials including a total of 2291 patients met inclusion criteria. 17 trials with 1168 patients were placebo-controlled (16 addressed single preparations, one a combination with four other plant extracts). Ten trials (eight single preparations, two combinations of hypericum and valeriana) with 1123 patients compared hypericum with other antidepressant or sedative drugs. Most trials were four to six weeks long. Participants usually had "neurotic depression" or "mild to moderate severe depressive disorders." Hypericum preparations were significantly superior to placebo (rate ratio 2.47; 95% confidence interval 1.69 to 3.61) and similarly effective as standard antidepressants (single preparations 1.01; 0.87 to 1.16, combinations 1.52; 0.78 to 2.94). The proportions of patients reporting side effects were 26.3% for hypericum single preparations vs. 44.7% for standard antidepressants (0.57; 0.47 to 0.69), and 14. 6% for combinations vs. 26.5% with amitriptyline or desipramine (0. 49; 0.23 to 1.04). REVIEWER'S CONCLUSIONS: There is evidence that extracts of hypericum are more effective than placebo for the short-term treatment of mild to moderately severe depressive disorders. The current evidence is inadequate to establish whether hypericum is as effective as other antidepressants. Further studies comparing hypericum with standard antidepressants in well defined groups of patients over longer observations periods, investigating long term side effects, and comparing different extracts and doses are needed.

Adult↗

Echinacea for preventing and treating the common cold.

BACKGROUND: Extracts of the plant Echinacea (family Compositae) are widely used in some European countries and the USA for upper respiratory tract infections. OBJECTIVES: The objective of this review was to assess the effects of preparations containing extracts of Echinacea in the prevention and treatment of the common cold. SEARCH STRATEGY: We searched the Cochrane Acute Respiratory Infections Group and Complementary Medicine Field's trials registers, MEDLINE, EMBASE, Phytodok and reference lists of articles. We also contacted researchers and manufacturers. Date of last search: Spring 1998. SELECTION CRITERIA: Randomised and quasi-randomised trials comparing preparations containing an extract of Echinacea compared with a placebo, no treatment, or another treatment for common colds. DATA COLLECTION AND ANALYSIS: At least two independent reviewers assessed trial quality and extracted data. MAIN RESULTS: Sixteen trials (eight prevention trials, and eight trials on treatment of upper respiratory tract infections) with a total of 3396 participants were included. Variation in preparations investigated and methodological quality of trials precluded quantitative meta-analysis. Overall, the results suggested that some Echinacea preparations may be better than placebo. REVIEWER'S CONCLUSIONS: The majority of the available studies report positive results. However there is not enough evidence to recommend a specific Echinacea product, or Echinacea preparations for the treatment or prevention of common colds.

Common Cold↗

Manual therapy for asthma.

BACKGROUND: A variety of manual therapies with similar postulated biologic mechanisms of action are commonly used to treat patients with asthma. Manual therapy practitioners are also varied, including physiotherapists, respiratory therapists, chiropractic and osteopathic physicians. A systematic review across disciplines is warranted. OBJECTIVES: To evaluate the evidence for the effects of manual therapies for treatment of patients with bronchial asthma. SEARCH STRATEGY: Trials were searched in computerized general (EMBASE, CINAHL and MEDLINE) and specialized databases (Cochrane Complementary Medicine Field, Cochrane Rehabilitation Field, ICL, and MANTIS). In addition, bibliographies from included studies were assessed, and authors of known studies were contacted for additional information about published and unpublished trials. Date of most recent search: December 1998. SELECTION CRITERIA: Trials were included if they: (1) were randomised; (2) included asthmatic children or adults; (3) examined one or more types of manual therapy; and (4) included clinical outcomes. DATA COLLECTION AND ANALYSIS: All three reviewers independently extracted data and assessed trial quality using a standard form. MAIN RESULTS: From an initial 316 unique citations, 48 full text articles were retrieved and evaluated, which resulted in nine citations to five RCTs (290 patients) suitable for inclusion. Trials could not be pooled statistically because studies that addressed similar interventions used disparate patient groups or outcomes. The methodological quality of one of two trials examining chiropractic manipulation was good and neither trial found significant differences between chiropractic spinal manipulation and a sham manoeuvre on any of the outcomes measured. Quality of the remaining three trials was poor. One small trial compared massage therapy with a relaxation control group and found significant differences in many of the lung function measures obtained. However, this trial had poor reporting characteristics and the data have yet to be confirmed. One small trial compared chest physiotherapy to placebo and one small trial compared footzone therapy to a no treatment control. Neither trial found differences in lung function between groups. REVIEWER'S CONCLUSIONS: There is insufficient evidence to support the use of manual therapies for patients with asthma. There is a need to conduct adequately-sized RCTs that examine the effects of manual therapies on clinically relevant outcomes. Future trials should maintain observer blinding for outcome assessments, and report on the costs of care and adverse events. Currently, there is insufficient evidence to support or refute the use of manual therapy for patients with asthma.

Adult↗

Speleotherapy for asthma.

BACKGROUND: Speleotherapy, the use of subterranean environments, is a therapeutic measure in the treatment of chronic obstructive airways diseases. It is virtually unknown in the UK or the US, but has considerable widespread use in some Central and Eastern European countries. OBJECTIVES: To review evidence for the efficacy of speleotherapy in the treatment of asthma. SEARCH STRATEGY: We searched electronic databases (Medline, Embase, Cochrane Airways group database), contacted speleotherapy centres and experts in the field, hand searched proceedings, and checked bibliographies of articles obtained to identify possible relevant publications. SELECTION CRITERIA: We included controlled clinical trials (i.e., both randomized and those not reporting the method of allocation) that compared clinical effects of speleotherapy with another intervention or no intervention in patients with chronic asthma. DATA COLLECTION AND ANALYSIS: Information concerning patients, interventions, results, and methodology were extracted in standardized manner by two independent reviewers and summarized descriptively. MAIN RESULTS: Three trials including a total of 124 asthmatic children met the inclusion criteria, but only one trial had reasonable methodological quality. Two trials reported that speleotherapy had a beneficial short-term effect on lung function. Other outcomes could not be assessed in a reliable manner. REVIEWER'S CONCLUSIONS: The available evidence does not permit a reliable conclusion as to whether speleo-therapeutic interventions are effective for the treatment of chronic asthma. Randomized controlled trials with long-term follow-up are necessary.

Air Ionization↗

Interaction of phosphatidylserine synthase from E. coli with lipid bilayers: coupled plasmon-waveguide resonance spectroscopy studies.

The interaction of phosphatidylserine (PS) synthase from Escherichia coli with lipid membranes was studied with a recently developed variant of the surface plasmon resonance technique, referred to as coupled plasmon-waveguide resonance spectroscopy. The features of the new technique are increased sensitivity and spectral resolution, and a unique ability to directly measure the structural anisotropy of lipid and proteolipid films. Solid-supported lipid bilayers with the following compositions were used: 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC); POPC-1-palmitoyl-2-oleoyl-sn-glycero-3-phosphate (POPA) (80:20, mol/mol); POPC-POPA (60:40, mol/mol); and POPC-1-palmitoyl-2-oleoyl-sn-glycero-3-[phospho-rac-(1-glycerol)] (POPG) (75:25, mol/mol). Addition of either POPA or POPG to a POPC bilayer causes a considerable increase of both the bilayer thickness and its optical anisotropy. PS synthase exhibits a biphasic interaction with the bilayers. The first phase, occurring at low protein concentrations, involves both electrostatic and hydrophobic interactions, although it is dominated by the latter, and the enzyme causes a local decrease of the ordering of the lipid molecules. The second phase, occurring at high protein concentrations, is predominantly controlled by electrostatic interactions, and results in a cooperative binding of the enzyme to the membrane surface. Addition of the anionic lipids to a POPC bilayer causes a 5- to 15-fold decrease in the protein concentration at which the first binding phase occurs. The results reported herein lend experimental support to a previously suggested mechanism for the regulation of the polar head group composition in E. coli membranes.

Anisotropy↗

Homeopathy and rheumatic disease.

Despite a growing interest in uncovering the basic mechanisms of arthritis, medical treatment remains symptomatic. Current medical treatments do not consistently halt the long-term progression of these diseases, and surgery may still be needed to restore mechanical function in large joints. Patients with rheumatic syndromes often seek alternative therapies, with homeopathy being one of the most frequent. Homeopathy is one of the most frequently used complementary therapies worldwide.

Arthritis, Rheumatoid↗

How to evaluate the effectiveness of complementary therapies.

The most important question about any treatment is whether it is effective. This article summarizes basic theoretic and practical aspects that are relevant to the evaluation of the effectiveness of a treatment. The factors that can explain why patients improve over time and the ways to separate these factors are outlined. It is explained why, theoretically, randomized clinical trials are the best method to answer questions about effectiveness. Reasons that such trials sometimes fail in practice to provide valid answers are listed. It is argued why evidence from randomized trials must be "complemented" by a variety of different research methods and quality assurance projects.

Complementary Therapies↗