Inclusion criteria were randomised controlled trials of complementary therapy treatment; non-migraneous headaches in adults; reporting on clinical outcomes; English language only.
Reviewers conducted searches of the main databases (MEDLINE) and references of retrieved reports though limited themselves to the English language only. Methodological quality of trials was assessed using an 18 point scale (van Tulder et al, 1997). The quality score of each trial was converted to a percentage where a rating of 0-40% indicated poor quality, 40-60% moderate quality and over 60% high quality. Reviewers provided a descriptive summary of all included reports and vote count of clinical outcome by type of intervention. Due to heterogeneity of trials, statistical pooling was not attempted.
Of the 24 included RCTs, 22 were of patients with TTH and two of CH. The trials were of the following complementary therapies: acupuncture, spinal manipulation, homeopathy, physiotherapy, electrotherapy, 'Tiger Balm' and therapeutic touch. The quality of the trials varied, but were generally of moderate quality. It was not possible to determine which aspects of methodological quality were high or low as reviewers only reported the total score. The reviewers presented very little information on the individual trials e.g. sensitivity of the trials, baseline values, adequacy of statistical testing, blinding status, and how and when outcomes were assessed. Therefore, it was difficult to verify their conclusions.
Acupuncture
There were four studies with quality scores of 61 to 69% reporting on 99 patients. Treatment duration ranged from six to 12 weeks, three studies were sham controlled and one compared acupuncture with physiotherapy. Two trials reported a significant difference favouring acupuncture over placebo for headache frequency. However, these two trials were very small with a combined total of only 39 patients. One sham controlled study reported no significant difference between the two groups.
One trial reported 'significant improvement' in the acupuncture and physiotherapy groups with no difference between the two groups. There were four lower quality studies (44 to 50%) reporting on 173 patients. Average duration of treatment was three months. Three of the studies were positive reporting acupuncture was better than sham control for headache frequency, better than no treatment for headache severity and better than medication (type unspecified) for level of improvement. One study was negative and showed physiotherapy was better than acupuncture for improvement of symptoms.
Spinal manipulation
Reviewers reported on six RCTs, two of these had at least one group size less than 10 and are not discussed further here. Of the remaining four RCTs, two were of TTH and two of CH. The trials had quality scores of 64 to 80%. All four trials used active control groups only, no sham/placebo controls. These included: soft tissue mobilisation, brief rest, ice pack, amitriptyline and soft tissue therapy. Three of the four studies were positive showing spinal manipulation to be more effective than the active comparators. Since none of these therapies are of proven efficacy, this does not rule out a placebo effect and does not provide convincing evidence for the efficacy of spinal manipulation for TTH and CH. The results were of dubious validity due to small group sizes in two of the trials and unclear diagnostic criteria for CH in two trials.
Electrotherapy
Four RCTs investigated electrotherapy, three were of Transcutaneous Electrical Nerve Stimulation (TENS) and one of cranial electrotherapy. Three of the trials were sham/placebo controlled and one compared TENS with relaxation, biofeedback or both combined. Quality scores ranged from 39 to 61%. Overall three trials were positive and one negative, however, the methodological quality of the trials was low including mixed headache diagnoses, lack of blinding and small group sizes. Physiotherapy Three RCTs with quality scores of 33 to 58, reporting on 147 patients. Treatment duration ranged from two to three months.
Physiotherapy
treatment included relaxation, stretching, TENS, ice therapy and teaching control of muscle tension. One trial compared acupuncture with physiotherapy the result for this trial is presented in acupuncture section above. One study compared amitriptyline plus physiotherapy versus physiotherapy alone, and one compared physiotherapy plus biofeedback with attention control. Both studies claim positive benefit of physiotherapy treatment. It is difficult to make any sense of these studies as the treatment modalities were mixed in each trial thus is impossible to determine the effect of each individual treatment. The trials are methodologically flawed producing biased results.
Homeopathy
One high quality (86%) trial that was both randomised and double blind compared individualised homeopathic treatment with placebo in 98 chronic TTH patients. After 12 weeks of treatment there was no difference between homeopathy and placebo on any outcome measure.
Tiger Balm
One RCT (quality 72%) compared 'Tiger Balm' topical ointment (analgesic/counter-irritant) with placebo or paracetamol 1000 mg in 57 patients with TTH. Both Tiger Balm and paracetamol were significantly better than placebo for pain relief up to three hours after a single treatment.
Therapeutic Touch
One RCT (quality 47%) compared therapeutic touch with sham touch in 60 patients. Twice as much pain relief was reported by real therapeutic touch patients as by the sham group immediately and four hours after the treatment.
