Self-reported nonmusculoskeletal responses to chiropractic intervention: a multination survey.

OBJECTIVE: To replicate a previous study of nonmusculoskeletal responses to chiropractic intervention and to establish whether such responses are influenced by the country of study, chiropractors' attitudes, and information to patients, patients' demographic profiles, and treatment regimens. METHODS: Information obtained through questionnaires by chiropractors and patients on return visit within 2 weeks of previous treatment from chiropractic practices in Canada, United States, Mexico, Hong-Kong, Japan, Australia, and South Africa. In all, 385 chiropractors collected valid data on 5607 patients. Spinal manipulation with or without additional therapy was the intervention provided by chiropractors. Outcome measures included self-reported improved nonmusculoskeletal reactions (allergy, asthma, breathing, circulation, digestion, hearing, heart function, ringing in the ears, sinus problems, urination, and others). RESULTS: The results from the previous study were largely reproduced. Positive reactions were reported by 2% to 10% of all patients and by 3% to 27% of those who reported to have such problems. Most common were improved breathing (27%), digestion (26%), and circulation (21%). Some variables were identified that somewhat influenced the outcome: patients informed that such reactions may occur (odds ratio [OR] 1.5), treatment to the upper cervical spine (OR 1.4), treatment to lower thoracic spine (OR 1.3), and female sex (OR 1.3). However, these had a very small "explanatory" value (pseudo R2 3%). CONCLUSION: A minority of patients with self-reported nonmusculoskeletal symptoms report definite improvement after chiropractic care, and very few report definite worsening. Future studies should use stringent criteria to investigate a possible treatment effect and concentrate on specific diagnostic subgroups such as digestive problems and tinnitus.

Extent measurement in localised low-back pain: a comparison of four methods.

Seventeen drawings of localised low-back pain were analysed by two assessors using 4 systems. Three were grid-based systems and one was by computer. The mean area or 'extent' was calculated to be 7.7%, 4.7%, 3.6% and 2.3% of the body outline using 45, 200, 560 and 61,102 section analyses, respectively. The computer-assisted method provided a significantly lower estimate of pain extent than the grid-based assessments as expected. Analysis of variance showed that the method of analysis provided greater source of variation than raters (P < 0.0001). Inter-rater reliability was high using all 4 systems calculated using intraclass correlation and the kappa statistic. Correlation coefficients of extent between the systems varied from 0.46 to 0.94. Correlation was highest between systems of adjacent magnitude of sections. It is concluded that grid-based assessment of small areas overestimates the actual area of pain and this may account for the lack of sensitivity to change in clinical status.