Opium, phencyclidine, and crack cocaine smoking associations with lung and upper aerodigestive tract cancers: exploratory findings from a case-control study in Los Angeles County.

Background: Illicit drug use has become a global epidemic, yet it is unclear if drug smoking increases the risk of tobacco-related cancers.Objectives: We aimed to evaluate hypothesized associations between smoking three drugs - opium, phencyclidine (PCP) and crack cocaine and lung and upper aerodigestive tract (UADT) cancers.Methods: A population-based case-control study with 611 lung cancer cases (50% male), 601 UADT cancers cases (76% male), and 1,040 controls (60% male) was conducted in Los Angeles County (1999-2004). Epidemiologic data including drug smoking histories were collected in face-to-face interviews. Associations were estimated with logistic regressions.Results: Adjusting for potential confounders, ever vs. never crack smoking was positively associated with UADT cancers (aOR = 1.56, 95% CI: 1.05, 2.33), and a dose-response relationship was observed for lifetime smoking frequency (p for trend = .024). Heavy (> median) vs. never crack smoking was associated with UADT cancers (aOR = 1.81, 95% CI: 1.07, 3.08) and lung cancer (aOR = 1.58, 95% CI: 0.88, 2.83). A positive association was also observed between heavy PCP smoking and UADT cancers (aOR = 2.29, 95% CI: 0.91, 5.79). Little or no associations were found between opium smoking and lung cancer or UADT cancers.Conclusion: The positive associations between illicit drug use and lung and/or UADT cancers suggest that smoking these drugs may increase the risk of tobacco-related cancers. Despite the low frequency of drug smoking and possible residual confounding, our findings may provide additional insights on the development of lung and UADT cancers.

Replicating Randomized Trial Results with Observational Data Using the Parametric g-Formula: An Application to Intravenous Iron Treatment in Hemodialysis Patients.

BACKGROUND: Reproducibility of clinical and epidemiologic research is important to generalize findings and has increasingly been scrutinized. A recently published randomized trial, PIVOTAL, evaluated high vs low intravenous iron dosing strategies to manage anemia in hemodialysis patients in the UK. Our objective was to assess the reproducibility of the PIVOTAL trial findings using data from a well-established cohort study, the Dialysis Outcomes and Practice Patterns Study (DOPPS). METHODS: To overcome the absence of randomization in the DOPPS, we applied the parametric g-formula, an extension of standardization to longitudinal data. We estimated the effect of a proactive high-dose vs reactive low-dose iron supplementation strategy on all-cause mortality (primary outcome), hemoglobin, two measures of iron concentration (ferritin and TSAT), and erythropoiesis-stimulating agent dose over 12 months of follow-up in 6325 DOPPS patients. RESULTS: Comparing high- vs low-iron dose strategies, the 1-year mortality risk difference was 0.020 (95% CI: 0.008, 0.031) and risk ratio was 1.20 (95% CI: 1.07, 1.33), compared with null 1-year findings in the PIVOTAL trial. Differences in secondary outcomes were directionally consistent but of lesser magnitude than in the PIVOTAL trial. CONCLUSION: Our findings are somewhat consistent with the recent PIVOTAL trial, with discrepancies potentially attributable to model misspecification and differences between the two study populations. In addition to the importance of our results to nephrologists and hence hemodialysis patients, our analysis illustrates the utility of the parametric g-formula for generalizing results and comparing complex and dynamic treatment strategies using observational data.

Folate intake and the risk of oral cavity and pharyngeal cancer: a pooled analysis within the International Head and Neck Cancer Epidemiology Consortium.

There are suggestions of an inverse association between folate intake and serum folate levels and the risk of oral cavity and pharyngeal cancers (OPCs), but most studies are limited in sample size, with only few reporting information on the source of dietary folate. Our study aims to investigate the association between folate intake and the risk of OPC within the International Head and Neck Cancer Epidemiology (INHANCE) Consortium. We analyzed pooled individual-level data from ten case-control studies participating in the INHANCE consortium, including 5,127 cases and 13,249 controls. Odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) were estimated for the associations between total folate intake (natural, fortification and supplementation) and natural folate only, and OPC risk. We found an inverse association between total folate intake and overall OPC risk (the adjusted OR for the highest vs. the lowest quintile was 0.65, 95% CI: 0.43-0.99), with a stronger association for oral cavity (OR = 0.57, 95% CI: 0.43-0.75). A similar inverse association, though somewhat weaker, was observed for folate intake from natural sources only in oral cavity cancer (OR = 0.64, 95% CI: 0.45-0.91). The highest OPC risk was observed in heavy alcohol drinkers with low folate intake as compared to never/light drinkers with high folate (OR = 4.05, 95% CI: 3.43-4.79); the attributable proportion (AP) owing to interaction was 11.1% (95% CI: 1.4-20.8%). Lastly, we reported an OR of 2.73 (95% CI:2.34-3.19) for those ever tobacco users with low folate intake, compared with nevere tobacco users and high folate intake (AP of interaction =10.6%, 95% CI: 0.41-20.8%). Our project of a large pool of case-control studies supports a protective effect of total folate intake on OPC risk.

Vitamin or mineral supplement intake and the risk of head and neck cancer: pooled analysis in the INHANCE consortium.

To investigate the potential role of vitamin or mineral supplementation on the risk of head and neck cancer (HNC), we analyzed individual-level pooled data from 12 case-control studies (7,002 HNC cases and 8,383 controls) participating in the International Head and Neck Cancer Epidemiology consortium. There were a total of 2,028 oral cavity cancer, 2,465 pharyngeal cancer, 874 unspecified oral/pharynx cancer, 1,329 laryngeal cancer and 306 overlapping HNC cases. Odds ratios (OR) and 95% confidence intervals (CIs) for self reported ever use of any vitamins, multivitamins, vitamin A, vitamin C, vitamin E, and calcium, beta-carotene, iron, selenium and zinc supplements were assessed. We further examined frequency, duration and cumulative exposure of each vitamin or mineral when possible and stratified by smoking and drinking status. All ORs were adjusted for age, sex, race/ethnicity, study center, education level, pack-years of smoking, frequency of alcohol drinking and fruit/vegetable intake. A decreased risk of HNC was observed with ever use of vitamin C (OR = 0.76, 95% CI = 0.59-0.96) and with ever use of calcium supplement (OR = 0.64, 95% CI = 0.42-0.97). The inverse association with HNC risk was also observed for 10 or more years of vitamin C use (OR = 0.72, 95% CI = 0.54-0.97) and more than 365 tablets of cumulative calcium intake (OR = 0.36, 95% CI = 0.16-0.83), but linear trends were not observed for the frequency or duration of any supplement intake. We did not observe any strong associations between vitamin or mineral supplement intake and the risk of HNC.

Coffee and tea intake and risk of head and neck cancer: pooled analysis in the international head and neck cancer epidemiology consortium.

BACKGROUND: Only a few studies have explored the relation between coffee and tea intake and head and neck cancers, with inconsistent results. METHODS: We pooled individual-level data from nine case-control studies of head and neck cancers, including 5,139 cases and 9,028 controls. Logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (95% CI), adjusting for potential confounders. RESULTS: Caffeinated coffee intake was inversely related with the risk of cancer of the oral cavity and pharynx: the ORs were 0.96 (95% CI, 0.94-0.98) for an increment of 1 cup per day and 0.61 (95% CI, 0.47-0.80) in drinkers of >4 cups per day versus nondrinkers. This latter estimate was consistent for different anatomic sites (OR, 0.46; 95% CI, 0.30-0.71 for oral cavity; OR, 0.58; 95% CI, 0.41-0.82 for oropharynx/hypopharynx; and OR, 0.61; 95% CI, 0.37-1.01 for oral cavity/pharynx not otherwise specified) and across strata of selected covariates. No association of caffeinated coffee drinking was found with laryngeal cancer (OR, 0.96; 95% CI, 0.64-1.45 in drinkers of >4 cups per day versus nondrinkers). Data on decaffeinated coffee were too sparse for detailed analysis, but indicated no increased risk. Tea intake was not associated with head and neck cancer risk (OR, 0.99; 95% CI, 0.89-1.11 for drinkers versus nondrinkers). CONCLUSIONS: This pooled analysis of case-control studies supports the hypothesis of an inverse association between caffeinated coffee drinking and risk of cancer of the oral cavity and pharynx. IMPACT: Given widespread use of coffee and the relatively high incidence and low survival of head and neck cancers, the observed inverse association may have appreciable public health relevance.

The impact of psychosocial factors on neck pain and disability outcomes among primary care patients: results from the UCLA Neck Pain Study.

PURPOSE: The purpose of this study is to estimate the associations of psychosocial factors with pain and disability outcomes among neck-pain patients enrolled in a randomized clinical trial of chiropractic treatments. METHODS: Neck-pain patients were randomized to one of 8 modes of chiropractic treatment. Health status and psychosocial variables were measured at baseline. Changes in neck pain severity and disability from baseline to 6 months were the primary outcome variables. Multivariable regression models were used to estimate effects of psychosocial variables adjusted for potential confounders. RESULTS: Of 960 eligible patients, 336 were enrolled and 80% were followed up through 6 months. Coping strategies involving self-assurance resulted in better disability outcomes, whereas getting angry or frustrated resulted in worse pain and disability outcomes. Participants with high levels of social support from individuals were more likely to experience clinically meaningful reductions in pain and disability. No consistent relations of internal health locus of control, and physical and psychological job demands with improvements in pain and disability were detected. CONCLUSIONS: We found some evidence that certain coping strategies and types of social support are associated with pain and disability outcomes in this population of largely subacute and chronic neck-pain patients.

A randomized trial of chiropractic and medical care for patients with low back pain: eighteen-month follow-up outcomes from the UCLA low back pain study.

STUDY DESIGN: Randomized clinical trial. OBJECTIVES: To compare the long-term effectiveness of medical and chiropractic care for low back pain in managed care and to assess the effectiveness of physical therapy and modalities among patients receiving medical or chiropractic care. SUMMARY OF BACKGROUND DATA: Evidence comparing the long-term relative effectiveness of common treatment strategies offered to low back pain patients in managed care is lacking. METHODS: A total of 681 low back pain patients presenting to a managed-care facility were randomized to chiropractic with or without physical modalities, or medical care with or without physical therapy, and followed for 18 months. The primary outcome variables are low back pain intensity, disability, and complete remission. The secondary outcome is participants' perception of improvement in low back symptoms. RESULTS: Of the 681 patients, 610 (89.6%) were followed through 18 months. Among participants not assigned to receive physical therapy or modalities, the estimated improvements in pain and disability and 18-month risk of complete remission were a little greater in the chiropractic group than in the medical group (adjusted RR of remission = 1.29; 95% CI = 0.80-2.07). Among participants assigned to medical care, mean changes in pain and disability and risk of remission were larger in patients assigned to receive physical therapy (adjusted RR = 1.69; 95% CI = 1.08-2.66). Among those assigned to chiropractic care, however, assignment to methods was not associated with improvement or remission (adjusted RR = 0.98; 95% CI = 0.62-1.55). Compared with medical care only patients, chiropractic and physical therapy patients were much more likely to perceive improvement in their low back symptoms. However, less than 20% of all patients were pain-free at 18 months. CONCLUSIONS: Differences in outcomes between medical and chiropractic care without physical therapy or modalities are not clinically meaningful, although chiropractic may result in a greater likelihood of perceived improvement, perhaps reflecting satisfaction or lack of blinding. Physical therapy may be more effective than medical care alone for some patients, while physical modalities appear to have no benefit in chiropractic care.

The use of complementary and alternative medicine among california adults with and without cancer.

This article examines the extent and correlates of complementary and alternative medicine (CAM) use among a population-based sample of California adults that is highly diverse in terms of sociodemographic characteristics and health status. As a follow-up to a state-wide health survey of 55,428 people, 9187 respondents were interviewed by phone regarding their use of 11 different types of CAM providers, special diets, dietary supplements, mind-body interventions, self-prayer and support groups. The sample included all participants in the initial survey who reported a diagnosis of cancer, all the non-white respondents, as well as a random sample of all the white respondents. The relation of CAM use to the respondents' demographic characteristics and health status is assessed. CAM use among Californians is generally high, and the demographic factors associated with high rates of CAM use are the same in California as have been found in other studies. Those reporting a diagnosis of cancer and those who report other chronic health problems indicate a similar level of visits to CAM providers. However, those with cancer are less likely to report using special diets, and more likely to report using support groups and prayer. Health status, gender, ethnicity and education have an independent impact upon CAM use among those who are healthy as well as those who report suffering from chronic health problems, although the precise relation varies by the type of CAM used.

Satisfaction as a predictor of clinical outcomes among chiropractic and medical patients enrolled in the UCLA low back pain study.

STUDY DESIGN: Observational study conducted within a randomized clinical trial. OBJECTIVES: The objective of this study is to estimate the effects of patient satisfaction on subsequent changes in pain and disability among low back pain patients randomized to chiropractic or medical care in a managed-care practice setting. SUMMARY OF BACKGROUND DATA: Recent studies of low back pain treatments have shown chiropractic patients to be more satisfied with their care than medical patients. However, little is known about the relation between patient satisfaction and clinical outcomes. METHODS: A total of 681 low back pain patients presenting to three southern California healthcare clinics and screened for serious spinal pathology and contraindications were randomized to medical care with and without physical therapy, and chiropractic care with and without physical modalities, and followed for 18 months. Satisfaction with back care was measured on a 40-point scale and observed at 4 weeks following randomization. The primary outcome variables, observed between 6 weeks and 18 months of follow-up, are average and most severe low back pain intensity in the past week, assessed with 0 to 10 numerical rating scales, low back-related disability, assessed with the 24-item Roland-Morris Disability Questionnaire, and remission from clinically meaningful pain and disability. Perceived change in low back symptoms was a secondary outcome. RESULTS: Greater satisfaction increased the odds of remission from clinically meaningful pain and disability at 6 weeks (adjusted odds ratio [OR] for 10-point increase in satisfaction = 1.61, 95% confidence interval [CI] = 0.99, 2.68), but not at 6, 12, or 18 months (6 months: adjusted OR = 1.05, 95% CI = 0.73, 1.52; 12 months: adjusted OR = 0.94, 95% CI = 0.67, 1.32; 18 months: adjusted OR = 1.07; 95% CI = 0.76, 1.50). Perception of improvement was greater among highly satisfied than less satisfied patients throughout the 18-month follow-up period. The estimated effects of satisfaction on clinical outcomes were similar for medical and chiropractic patients. CONCLUSIONS: Patient satisfaction may confer small short-term clinical benefits for low back pain patients. Long-term perceived improvement may reflect, in part, perceived past improvement as measured by satisfaction.

Effects of recreational physical activity and back exercises on low back pain and psychological distress: findings from the UCLA Low Back Pain Study.

OBJECTIVES: We sought to estimate the effects of recreational physical activity and back exercises on low back pain, related disability, and psychological distress among patients randomized to chiropractic or medical care in a managed care setting. METHODS: Low back pain patients (n=681) were randomized and followed for 18 months. Participation in recreational physical activities, use of back exercises, and low back pain, related disability, and psychological distress were measured at baseline, at 6 weeks, and at 6, 12, and 18 months. Multivariate logistic regression modeling was used to estimate adjusted associations of physical activity and back exercises with concurrent and subsequent pain, disability, and psychological distress. RESULTS: Participation in recreational physical activities was inversely associated--both cross-sectionally and longitudinally--with low back pain, related disability, and psychological distress. By contrast, back exercise was positively associated--both cross-sectionally and longitudinally--with low back pain and related disability. CONCLUSIONS: These results suggest that individuals with low back pain should refrain from specific back exercises and instead focus on nonspecific physical activities to reduce pain and improve psychological health.

Frequency and clinical predictors of adverse reactions to chiropractic care in the UCLA neck pain study.

STUDY DESIGN: Randomized clinical trial. OBJECTIVES: To document the types and frequencies of adverse reactions associated with the most common chiropractic treatments for neck pain, and to identify possible clinical predictors of adverse reactions to chiropractic treatment. SUMMARY OF BACKGROUND DATA: Chiropractic care is frequently sought by patients for relief from neck pain; however, adverse reactions related to its primary modes of treatment have not been well examined. METHODS: A total of 336 patients with neck pain presenting to 4 southern California health care clinics were randomized in a balanced 2 x 2 x 2 factorial design to manipulation with or without heat, and with or without electrical muscle stimulation (EMS); and mobilization with or without heat and with or without EMS. Discomfort or unpleasant reactions from chiropractic care were self-assessed at 2 weeks after the randomization/baseline visit. RESULTS: Of the 280 participants (83%) who responded, 85 (30.4%) had 212 adverse symptoms as a result of chiropractic care. Increased neck pain or stiffness was the most common symptom, reported by 25% of the participants. Less common were headache and radiating pain. Patients randomized to manipulation were more likely than those randomized to mobilization to have an adverse symptom occurring within 24 hours of treatment (adjusted odds ratio [OR] = 1.44, 95% confidence interval [CI] = 0.83, 2.49). Heat and EMS were only weakly associated with adverse symptoms (heat: OR = 0.94, 95% CI = 0.54, 1.62; EMS: OR = 1.09, 95% CI = 0.63, 1.89). Moderate-to-severe neck disability at baseline was strongly associated with adverse neurologic symptoms (OR = 5.70, 95% CI = 1.49, 21.80). CONCLUSIONS: Our results suggest that adverse reactions to chiropractic care for neck pain are common and that despite somewhat imprecise estimation, adverse reactions appear more likely to follow cervical spine manipulation than mobilization. Given the possible higher risk of adverse reactions and lack of demonstrated effectiveness of manipulation over mobilization, chiropractors should consider a conservative approach for applying manipulation to their patients, especially those with severe neck pain.

Economic evaluation of four treatments for low-back pain: results from a randomized controlled trial.

OBJECTIVE: We sought to compare total outpatient costs of 4 common treatments for low-back pain (LBP) at 18-months follow-up. METHODS: Our work reports on findings from a randomized controlled trial within a large medical group practice treating HMO patients. Patients (n = 681) were assigned to 1 of 4 treatment groups, ie, medical care only (MD), medical care with physical therapy (MDPt), chiropractic care only (DC), or chiropractic care with physical modalities (DCPm). Total outpatient costs, excluding pharmaceuticals, were measured at 18 months. We did not perform a cost-effectiveness analysis because previously published findings showed no clinically meaningful difference in outcomes among the 4 treatment groups. Thirty-seven participants were lost to follow-up at 18 months, leaving a final sample size of n = 654. RESULTS: Adjusting for covariates, DC was 51.9% more expensive than MD (P < 0.001), DCPm 3.2% more expensive than DC (P = 0.76), and MDPt 105.8% more expensive than MD (P < 0.001). The adjusted mean outpatient costs per treatment group were 369 US dollars for MD, 560 US dollars for DC, 579 US dollars for DCPm, and 760 US dollars for MDPt. CONCLUSIONS: This study is the first randomized trial to show higher costs for chiropractic care without producing better clinical outcomes, but our findings are likely to understate the costs of medical care with or without physical therapy because of the absence of pharmaceutical data. Physical therapy provided in combination with medical care and physical modalities provided in combination with chiropractic care do not appear to be cost-effective strategies for treatment of LBP; they produce higher costs without clinically significant improvements in outcome.

Adverse reactions to chiropractic treatment and their effects on satisfaction and clinical outcomes among patients enrolled in the UCLA Neck Pain Study.

BACKGROUND: Minor side effects associated with chiropractic are common. However, little is known about their predictors or the effects of reactions on satisfaction and clinical outcomes. OBJECTIVE: The objectives of this study are to compare the relative effects of cervical spine manipulation and mobilization on adverse reactions and to estimate the effects of adverse reactions on satisfaction and clinical outcomes among patients with neck pain. METHODS: Neck pain patients were randomized to receive cervical spine manipulation or mobilization. At 2 weeks, subjects were queried about possible treatment-related adverse reactions and followed for 6 months with assessments for pain and disability at 2, 6, 13, and 26 weeks. Numerical rating scales and the Neck Disability Index were used to measure pain and disability. Perceived improvement and satisfaction with care were assessed at 4 weeks. RESULTS: Of 960 eligible patients, 336 enrolled and 280 responded to the adverse event questionnaire. Thirty percent of respondents reported at least 1 adverse symptom, most commonly increased pain and headache. Patients randomized to manipulation were more likely than those randomized to mobilization to report an adverse reaction (adjusted odds ratio = 1.44, 95% confidence interval = 0.85, 2.43). Subjects reporting adverse reactions were less satisfied with care and less likely to have clinically meaningful improvements in pain and disability. CONCLUSIONS: Adverse reactions are more likely to be reported following cervical spine manipulation than mobilization. Chiropractors may reduce iatrogenesis and increase satisfaction and perhaps clinical outcomes by mobilizing rather than manipulating their neck pain patients.

Use of a Markov transition model to analyse longitudinal low-back pain data.

In a randomized clinical trial to assess the effectiveness of different strategies for treating low-back pain in a managed-care setting, 681 adult patients presenting with low-back pain were randomized to four treatment groups: medical care with and without physical therapy; and chiropractic care with and without physical modalities. Follow-up information was obtained by questionnaires at two and six weeks, six, 12 and 18 months and by a telephone interview at four weeks. One outcome measurement at each follow-up is the patient's self-report on the perception of low-back pain improvement from the previous survey, recorded as 'A lot better,' 'A little better,' 'About the same' and 'Worse.' Since the patient's perception of improvement may be influenced by past experience, the outcome is analysed using a transition (first-order Markov) model. Although one could collapse categories to the point that logistic regression analysis with repeated measurements could be used, here we allow for multiple categories by relating transition probabilities to covariates and previous outcomes through a polytomous logistic regression model with Markov structure. This approach allows us to assess not only the effects of treatment assignment and baseline characteristics but also the effects of past outcomes in analysing longitudinal categorical data.

A randomized trial of medical care with and without physical therapy and chiropractic care with and without physical modalities for patients with low back pain: 6-month follow-up outcomes from the UCLA low back pain study.

STUDY DESIGN: A randomized clinical trial. OBJECTIVES: To compare the effectiveness of medical and chiropractic care for low back pain patients in managed care; to assess the effectiveness of physical therapy among medical patients; and to assess the effectiveness of physical modalities among chiropractic patients. SUMMARY OF BACKGROUND DATA: Despite the burden that low back pain places on patients, providers, and society, the relative effectiveness of common treatment strategies offered in managed care is unknown. METHODS: Low back pain patients presenting to a large managed care facility from October 30, 1995, through November 9, 1998, were randomly assigned in a balanced design to medical care with and without physical therapy and to chiropractic care with and without physical modalities. The primary outcome variables are average and most severe low back pain intensity in the past week, assessed with 0 to 10 numerical rating scales, and low back-related disability, assessed with the 24-item Roland-Morris Disability Questionnaire. RESULTS: Of 1,469 eligible patients, 681 were enrolled; 95.7% were followed through 6 months. The mean changes in low back pain intensity and disability of participants in the medical and chiropractic care-only groups were similar at each follow-up assessment (adjusted mean differences at 6 months for most severe pain, 0.27, 95% confidence interval, -0.32-0.86; average pain, 0.22, -0.25-0.69; and disability, 0.75, -0.29-1.79). Physical therapy yielded somewhat better 6-month disability outcomes than did medical care alone (1.26, 0.20-2.32). CONCLUSIONS: After 6 months of follow-up, chiropractic care and medical care for low back pain were comparable in their effectiveness. Physical therapy may be marginally more effective than medical care alone for reducing disability in some patients, but the possible benefit is small.

Comparing the satisfaction of low back pain patients randomized to receive medical or chiropractic care: results from the UCLA low-back pain study.

OBJECTIVES: This study examined the difference in satisfaction between patients assigned to chiropractic vs medical care for treatment of low back pain in a managed care organization. METHODS: Satisfaction scores (on a 10-50 scale) after 4 weeks of follow-up were compared among 672 patients randomized to receive medical or chiropractic care. RESULTS: The mean satisfaction score for chiropractic patients was greater than the score for medical patients (crude difference = 5.5; 95% confidence interval = 4.5, 6.5). Self-care advice and explanation of treatment predicted satisfaction and reduced the estimated difference between chiropractic and medical patients' satisfaction. CONCLUSIONS: Communication of advice and information to patients with low back pain increases their satisfaction with providers and accounts for much of the difference between chiropractic and medical patients' satisfaction.

A randomized trial of chiropractic manipulation and mobilization for patients with neck pain: clinical outcomes from the UCLA neck-pain study.

OBJECTIVES: This study compared the relative effectiveness of cervical spine manipulation and mobilization for neck pain. METHODS: Neck-pain patients were randomized to the following conditions: manipulation with or without heat, manipulation with or without electrical muscle stimulation, mobilization with or without heat, and mobilization with or without electrical muscle stimulation. RESULTS: Of 960 eligible patients, 336 enrolled in the study. Mean reductions in pain and disability were similar in the manipulation and mobilization groups through 6 months. CONCLUSIONS: Cervical spine manipulation and mobilization yield comparable clinical outcomes.

Second Prize: The effectiveness of physical modalities among patients with low back pain randomized to chiropractic care: findings from the UCLA low back pain study.

BACKGROUND: Although chiropractors often use physical modalities with spinal manipulation, evidence that modalities yield additional benefits over spinal manipulation alone is lacking. OBJECTIVE: The purpose of the study was to estimate the net effect of physical modalities on low back pain (LBP) outcomes among chiropractic patients in a managed-care setting. METHODS: Fifty percent of the 681 patients participating in a clinical trial of LBP treatment strategies were randomized to chiropractic care with physical modalities (n = 172) or without physical modalities (n = 169). Subjects were followed for 6 months with assessments at 2, 4, and 6 weeks and at 6 months. The primary outcome variables were average and most severe LBP intensity in the past week, assessed with numerical rating scales (0-10), and low back-related disability, assessed with the 24-item Roland-Morris Disability Questionnaire. RESULTS: Almost 60% of the subjects had baseline LBP episodes of more than 3 months' duration. The 6-month follow-up was 96%. The adjusted mean differences between groups in improvements in average and most severe pain and disability were clinically insignificant at all follow-up assessments. Clinically relevant improvements in average pain and disability were more likely in the modalities group at 2 and 6 weeks, but this apparent advantage disappeared at 6 months. Perceived treatment effectiveness was greater in the modalities group. CONCLUSIONS: Physical modalities used by chiropractors in this managed-care organization did not appear to be effective in the treatment of patients with LBP, although a small short-term benefit for some patients cannot be ruled out.

The impact of treatment confidence on pain and related disability among patients with low-back pain: results from the University of California, Los Angeles, low-back pain study.

BACKGROUND CONTEXT: Although many researchers and practitioners believe that patients' positive expectations of their treatment favorably influence clinical outcomes, there is little scientific evidence to support this belief. PURPOSE: To describe the level of patients' initial confidence in the success of their assigned treatment, by treatment group and other factors; and to estimate the effects of treatment confidence on subsequent changes in low-back pain and related disability. STUDY DESIGN AND PATIENT SAMPLE: Randomized clinical trial involving 681 patients treated for low-back pain in a managed-care facility in Southern California. OUTCOME MEASURES: Treatment confidence; and changes in three clinical measures of low-back pain: average pain, most severe pain and back-pain-related disability. METHODS: Patients were randomly assigned to one of four treatment groups: medical care with and without physical therapy, and chiropractic care with and without physical modalities. Information was collected by questionnaires at baseline, 2 weeks, 6 weeks and 6 months. Treatment confidence was measured just after randomization on a scale of 0 to 10. RESULTS: Treatment confidence was lowest, on average, for patients assigned to medical care only and highest for patients assigned to medical care plus physical therapy. Other predictors of high treatment confidence were having acute pain and being older, female and nonwhite. Although treatment confidence was only weakly associated with subsequent changes in low-back pain or disability in the total sample, high treatment confidence was associated with greater improvement among patients assigned to medical care plus physical therapy. CONCLUSIONS: Initial confidence in treatment for low-back pain varies by type of care and other factors. Higher confidence may have some beneficial effect on the course of low-back pain in certain patients, but this effect may depend on the type of interaction between client and provider.