Search PubMed⌕ Search

Biomedical subjects

C Bombardier

Publications and source records attributed to C Bombardier.

At least 37 records · Page 2Linked to original sources
PubMed2001

Biomechanical and psychosocial risk factors for low back pain at work.

OBJECTIVES: This study determined whether the physical and psychosocial demands of work are associated with low back pain. METHODS: A case-control approach was used. Case subjects (n = 137) reported a new episode of low back pain to their employer, a large automobile manufacturing complex. Control subjects were randomly selected from the study base as cases accrued (n = 179) or were matched to cases by exact job (n = 65). Individual, clinical, and psychosocial variables were assessed by interview. Physical demands were assessed with direct workplace measurements of subjects at their usual jobs. The analysis used multiple logistic regression adjusted for individual characteristics. RESULTS: Self-reported risk factors included a physically demanding job, a poor workplace social environment, inconsistency between job and education level, better job satisfaction, and better coworker support. Low job control showed a borderline association. Physical-measure risk factors included peak lumbar shear force, peak load handled, and cumulative lumbar disc compression. Low body mass index and prior low back pain compensation claims were the only significant individual characteristics. CONCLUSIONS: This study identified specific physical and psychosocial demands of work as independent risk factors for low back pain.

Adult↗
PubMed2001

Looking for important change/differences in studies of responsiveness. OMERACT MCID Working Group. Outcome Measures in Rheumatology. Minimal Clinically Important Difference.

The purpose of this paper is to describe a classification system for studies of responsiveness that was designed to help organize these studies, and identify those with the potential to provide information on minimal clinically important difference (MCID). We developed a 3 dimensional cube into which studies of responsiveness can be categorized based on their evaluation of 3 attributes: 1. individual or group setting; 2. which scores are contrasted; and 3. the type of change or difference being assessed. We present and discuss examples of studies that fit into categories in the classification cube. This classification system helps to focus attention on whether the literature is able to provide information on the specific type of change a person is interested in. It reinforces that the ability of an instrument to detect a certain category of discrimination within the cube does not mean it will necessarily be responsive to another category. The cube has been shown here as a means to separate out studies that address important change. These studies can then be examined as the source of information on MCID.

Clinical Trials as Topic↗
PubMed2001

Minimal clinically important difference. Low back pain: outcome measures.

A proposed standard "core set" of outcome measures for low back pain includes 5 domains: back-specific function, generic health status, pain, work disability, and patient satisfaction. This paper focuses on the 2 recommended back-specific measures of function: the Roland-Morris Disability Questionnaire (RDQ) and the Oswestry Disability Index (ODI). We specifically address their ability to measure change. A systematic review of the literature identified a total of 78 and 71 (RDQ and ODI, respectively) articles as potentially relevant. Detailed tables are provided for each citation, with the type of back pain population studied, the type of change measured, the estimate of change, and the interval over which the change was studied. These tables should be used as a reference for sample size calculation. The responsiveness of the RDQ found in the literature ranges from 2 to 8 points on its 0 to 24 scale depending on what change is being measured. As a rough guide, Roland recommends that a change in 2-3 points on the RDQ should be considered the minimum clinically important change. Choosing any value larger than 5 in designing a clinical trial would risk underpowering the trial, since fewer patients are needed if a trial is designed on the basis of a large change score.

Clinical Trials as Topic↗
PubMed2001

Physical therapy management of low back pain: an exploratory survey of therapist approaches.

BACKGROUND AND PURPOSE: Since the release of acute low back pain management guidelines in 1994, little was known about the effect of these guidelines on clinical practice. The purpose of this study was to examine physical therapists' reported management of acute and subacute lumbar impairment. SUBJECTS: One in 10 registered physical therapists who were randomly selected from southern Ontario, Canada, (n=454) and all registered physical therapists from northern Ontario (n=331) were surveyed. METHODS: In the questionnaire, case scenarios covered 3 areas related to the management of lumbar impairment: (1) physical examination, (2) treatment and recommendations, and (3) therapists' beliefs regarding its management. RESULTS: Five hundred sixty-nine questionnaires were returned (response rate=72.5%). Only data obtained for therapists (n=274) whose weekly workload included more than 10% of people with lumbar impairment were used in the analysis. Overall, patient education, exercise, and electrotherapeutic and thermal modalities were the preferred interventions for acute lumbar impairment (symptom onset of less than 5 weeks) with or without sciatica, whereas exercise and work modification were preferred for subacute lumbar impairment (symptom onset of 5 weeks or longer). There was a trend of using electrotherapeutic and thermal modalities with uncertain effectiveness. Only 46.3% of the therapists agreed or strongly agreed that practice guidelines were useful for managing lumbar impairment. DISCUSSION AND CONCLUSION: Although the physical therapists surveyed, in general, followed the guidelines in managing acute lumbar impairment, they felt uncertain regarding the value of practice guidelines. Future research should focus on identifying effective treatment approaches and exploring the effectiveness of practice guidelines.

Acute Disease↗
PubMed2000

Outcome assessments in the evaluation of treatment of spinal disorders: summary and general recommendations.

Clinicians and researchers increasingly recognize the importance of the patient's perspective in the evaluations of the effectiveness of treatment. The rapid growth in the number and types of patient-based outcome measures can be confusing. This supplement provides a state-of-the-art review of the available tools. In this paper, the key recommendations from the participating authors are summarized. A core set of measures should include the following five domains: back specific function, generic health status, pain, work disability, and patient satisfaction. Two commonly used measures of back-specific function are recommended: the Roland-Morris Disability Questionnaire and the Oswestry Disability Index. Among the generic measures, the SF-36 strikes the best balance between length, reliability, validity, responsiveness, and experience in large populations of patients with back pain. Moreover, the SF-36 Bodily Pain Scale provides a brief measure of pain intensity and pain interference with activities. Health-related work disability should include at a minimum a measure of work status and work-time loss. For those who are still at work, new measures are being developed to measure health-related work limitations. No single measure of patient satisfaction is clearly preferred but guiding principles are provided to choose among available measures. In addition to the five recommended domains, preference-based health outcome measures, including patients utilities, may be useful when there is a need to value alternative health outcomes.

Disability Evaluation↗
PubMed2000

Comparison of upper gastrointestinal toxicity of rofecoxib and naproxen in patients with rheumatoid arthritis. VIGOR Study Group.

BACKGROUND: Each year, clinical upper gastrointestinal events occur in 2 to 4 percent of patients who are taking nonselective nonsteroidal antiinflammatory drugs (NSAIDs). We assessed whether rofecoxib, a selective inhibitor of cyclooxygenase-2, would be associated with a lower incidence of clinically important upper gastrointestinal events than is the nonselective NSAID naproxen among patients with rheumatoid arthritis. METHODS: We randomly assigned 8076 patients who were at least 50 years of age (or at least 40 years of age and receiving long-term glucocorticoid therapy) and who had rheumatoid arthritis to receive either 50 mg of rofecoxib daily or 500 mg of naproxen twice daily. The primary end point was confirmed clinical upper gastrointestinal events (gastroduodenal perforation or obstruction, upper gastrointestinal bleeding, and symptomatic gastroduodenal ulcers). RESULTS: Rofecoxib and naproxen had similar efficacy against rheumatoid arthritis. During a median follow-up of 9.0 months, 2.1 confirmed gastrointestinal events per 100 patient-years occurred with rofecoxib, as compared with 4.5 per 100 patient-years with naproxen (relative risk, 0.5; 95 percent confidence interval, 0.3 to 0.6; P<0.001). The respective rates of complicated confirmed events (perforation, obstruction, and severe upper gastrointestinal bleeding) were 0.6 per 100 patient-years and 1.4 per 100 patient-years (relative risk, 0.4; 95 percent confidence interval, 0.2 to 0.8; P=0.005). The incidence of myocardial infarction was lower among patients in the naproxen group than among those in the rofecoxib group (0.1 percent vs. 0.4 percent; relative risk, 0.2; 95 percent confidence interval, 0.1 to 0.7); the overall mortality rate and the rate of death from cardiovascular causes were similar in the two groups. CONCLUSIONS: In patients with rheumatoid arthritis, treatment with rofecoxib, a selective inhibitor of cyclooxygenase-2, is associated with significantly fewer clinically important upper gastrointestinal events than treatment with naproxen, a nonselective inhibitor.

Adult↗
PubMed2000

Prognostic factors for time receiving workers' compensation benefits in a cohort of patients with low back pain.

STUDY DESIGN: Prospective inception cohort study. OBJECTIVE: To develop a prognostic model that predicts time receiving workers' compensation benefits for low back pain claimants. SUMMARY OF BACKGROUND DATA: As the cost and difficulty of managing low back pain escalate, any predictor of outcome is advantageous. METHODS: To obtain the outcome and predictor variables, patient data from two separate databases were linked: a clinical database and an administrative (Ontario workers' compensation) database. Claimants injured between January 1 and December 31, 1994, were included and observed for 1 year from the date of accident. The outcome variable was cumulative number of calendar days receiving benefits. RESULTS: Multivariable Cox proportional hazards regression (forward stepwise) showed eight significant predictors; five were associated with increased time receiving benefits compared with their reference groups: 1) working in the construction industry, 2) older age, 3) lag time from injury to treatment, 4) pain referred into the leg, and 5) three or more positive Waddell nonorganic signs. Three predictors were associated with reduced time receiving benefits: 1) higher values of questionnaire score, 2) intermittent pain, and 3) a previous episode of back pain. A predictive score was calculated to categorize claimants as at high or low risk for chronicity. When an arbitrary cutoff point was set at the 75th percentile of predictive score, negative predictive value was 94%. CONCLUSION: This research identified eight factors for time receiving workers' compensation benefits among claimants with low back pain. This model discriminates between high- and low-risk claimants. Few low-risk claimants continued to receive benefits for more than 3 months.

Adult↗
PubMed2000

Back schools for non-specific low back pain.

BACKGROUND: Since the introduction of the Swedish back school in 1980, the content of back schools has changed and appears to vary widely today. Back schools are frequently used in the treatment of low back pain patients. OBJECTIVES: The objective of this systematic review was to assess the effects of back schools for patients with non-specific low back pain. SEARCH STRATEGY: We searched the Medline and Embase databases up to December 1997 and the Cochrane Controlled Trials Register up to December 1998 if reported in English, Dutch, French or German. We also screened references given in relevant reviews and identified randomised trials. SELECTION CRITERIA: Only randomised trials that reported on any type of back school for non-specific low back pain were included. DATA COLLECTION AND ANALYSIS: Two reviewers blinded with respect to authors, institution and journal independently extracted the data and assessed trial quality. Our preset "high quality" level was 6 or more out of 11 internal validity criteria with positive scores. As data were statistically and clinically too heterogeneous, a qualitative review (best evidence synthesis) was performed. The evidence was classified into 4 levels (strong, moderate, limited or no evidence) taking into account the methodological quality of the studies. MAIN RESULTS: Fifteen RCTs were included in our systematic review. Overall, the methodological quality was low. Only 3 trials were considered high quality. It was not possible to make relevant subgroup analyses for radiation versus no radiation or to have a relevant subgroup of studies reporting on acute low back pain only. The results indicate that there is moderate evidence that back schools have better short-term effects than other treatments for chronic low back pain, and that there is moderate evidence that back schools in an occupational setting are more effective compared to 'placebo' or waiting list controls. REVIEWER'S CONCLUSIONS: Back schools may be effective for patients with recurrent and chronic low back pain in occupational settings, but little is known about the cost-effectiveness of back schools.

Exercise↗
PubMed2000

Injectable gold for rheumatoid arthritis.

OBJECTIVES: To estimate the short-term benefit and risk of side-effects of injectable gold for rheumatoid arthritis. SEARCH STRATEGY: We searched the Cochrane Musculoskeletal Group trials register, and Medline, up to July 1997, using the search strategy developed by the Cochrane Collaboration (Dickersin 1994). The search was complemented with bibliography searching of the reference list of the trials retrieved from the electronic search. Key experts in the area were contacted for further published and unpublished articles. SELECTION CRITERIA: Randomized clinical trials (RCT) comparing injectable gold against placebo in patients with rheumatoid arthritis were included. DATA COLLECTION AND ANALYSIS: Methodological quality of the RCTs was asessed by two reviewers (MS, BS) (kappa=1.0). Rheumatoid arthritis outcome measures were extracted by two reviewers from the publications for the 6 month endpoint. Sufficient data was obtained to conduct a pooled analysis of the number of swollen joints, physician global assessment, patient global assessment and erythrocyte sedimentation rate (ESR). Results were analyzed as standardized weighted mean differences for swollen joints and global assessments and weighted mean differences for ESR. Toxicity was evaluated with pooled odds ratios for withdrawals. Heterogeneity was estimated using a chi-square test. Fixed effects models were used throughout. MAIN RESULTS: Four trials and 415 patients were included. A statistically significant benefit was observed for injectable gold when compared to placebo. The standardized weighted difference (effect size) between gold and placebo for the number of swollen joints was -0.5, translating into a percentage change of 30% in favour of gold adjusted for placebo. Statistically significant differences were also observed for ESR and patient and physician assessments. Twenty two percent of the treated patients withdrew from toxicity compared to 4% of controls (OR=3.9 - 95%Cl: 2.1 - 7.2). REVIEWER'S CONCLUSIONS: Although its use can be limited by the incidence of serious toxicity, injectable gold has an important clinically and statistically significant benefit in the short term treatment of patients with rheumatoid arthritis.

Antirheumatic Agents↗
PubMed2000

Clinical improvement as reflected in measures of function and health-related quality of life following treatment with leflunomide compared with methotrexate in patients with rheumatoid arthritis: sensitivity and relative efficiency to detect a treatment effect in a twelve-month, placebo-controlled trial. Leflunomide Rheumatoid Arthritis Investigators Group.

OBJECTIVE: To examine correlations between clinical improvement as defined by the American College of Rheumatology (ACR) responder analysis and clinical improvement as determined by 4 function and/or health-related quality of life measures, and to estimate the sensitivity and relative efficiency of these measures compared with changes in the tender joint count in patients with rheumatoid arthritis (RA). METHODS: A 52-week, multicenter, double-blind controlled trial was conducted to compare treatment with leflunomide (n = 182), methotrexate (n = 180), or placebo (n = 118) in patients with active RA. ACR response rates and improvement in scores on the Health Assessment Questionnaire (HAQ), Problem Elicitation Technique (PET), and Medical Outcomes Survey Short Form 36 (SF-36) were compared in 438 of the patients. RESULTS: In comparing leflunomide with placebo, the patient global assessment, HAQ disability index, and SF-36 bodily pain scale were most responsive to treatment group differences. The modified HAQ (M-HAQ), PET Top 5, SF-36 physical component score, physician global assessment, pain intensity scale, and SF-36 physical functioning scale were more responsive to treatment group differences than was the tender joint count. In comparing methotrexate with placebo, the patient and physician global assessments were most responsive. These 2 measures, as well as the pain intensity scale and the C-reactive protein level, were more responsive to treatment group differences than was the tender joint count, while the SF-36 mental health component score was least responsive. A close correlation between changes in the M-HAQ and HAQ scores indicated that the M-HAQ was similarly responsive to change over time. Improvements in the PET, SF-36 physical component score, bodily pain, and physical functioning scales correlated with the ACR responder status. CONCLUSION: Both disease-specific and generic measures of function and health-related quality of life detect improvements in RA patients. Using both types of measures for evaluating therapies will identify discernible changes that are important to patients, and will facilitate comparisons across different disease states.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2000

Use of grade membership analysis to profile the practice styles of individual physicians in the management of acute low back pain.

The objective of this study was to investigate Grade of Membership analysis (GoM) as a means of profiling the practice styles of individual physicians. GoM uses maximum likelihood techniques to estimate occurrences of management items that define unique practice styles. It also provides statistical estimates (grade of membership coefficients) of how well each individual physician's practice fits the identified styles. Data sources were responses to a mailed survey asking 814 physicians to select from predetermined management options in three scenarios depicting patients with acute low back pain. Four distinct types of practice style were identified: watchful waiting; investigative; guideline based; and physiotherapy focused. Most physicians were characterized by high grades of membership in the two profiles that most closely matched existing guidelines for the management of acute low back pain. GoM successfully identified characteristic practice styles, and the GoM coefficients obtained provided descriptions of individual management approaches. GoM is data driven and less subject to judgment than opinion-based measures of performance. It has several potential applications in identifying physicians for whom some form of intervention would be beneficial.

Acute Disease↗
PubMed2000

Meta-analysis of treatment termination rates among rheumatoid arthritis patients receiving disease-modifying anti-rheumatic drugs.

OBJECTIVE: To summarize the evidence on treatment withdrawal rates reported in observational studies and randomized controlled trials (RCTs) of methotrexate (MTX), parenteral gold (GST), sulphasalazine (SSZ) and hydroxychloroquine (HCQ) among patients with rheumatoid arthritis (RA). METHODS: Two independent Medline searches were used to retrieve relevant studies published between 1966 and 1997. Those which disclosed information on the number of patients withdrawing from the drug were retained. Cumulative probabilities of survival on treatment were then computed using actuarial survival estimates, and differences were tested using log-rank, Wilcoxon and Cox proportional hazards tests. RESULTS: A total of 159 studies provided withdrawal information, and the numbers of patients who withdrew, in general or because of inefficacy or toxicity, could be abstracted from 110 studies contributing 142 treatment arms (MTX, 48; GST, 56; SSZ, 22; HCQ, 16). Data for HCQ were available only up to 24 months, but combined percentages of patients estimated to have continued MTX, GST or SSZ, respectively, for 60 months were 36, 23 and 22% when all failures were considered, 75, 73 and 53% when withdrawals due to lack of efficacy alone were considered, and 65, 36 and 48% when only withdrawals due to toxicity were taken into account. The Cox proportional hazards test performed on all withdrawals, after adjusting for year of publication and type of study, revealed that patients remained on MTX significantly longer than they did on the other three agents; however, the patients stayed significantly longer on GST than MTX when withdrawals for inefficacy were analysed separately. No significant differences in withdrawal rates were noted between observational studies and RCTs. CONCLUSION: Patients with RA stay significantly longer on MTX than on other disease-modifying anti-rheumatic drugs. Higher withdrawal rates among those given GST are mainly due to high toxicity, whereas the majority of withdrawals from SSZ and HCQ result from lack of efficacy. Withdrawal rates in observational studies are similar to those reported in RCTs.

Antirheumatic Agents↗
PubMed2000

Consequences of delayed therapy with second-line agents in rheumatoid arthritis: a 3 year followup on the hydroxychloroquine in early rheumatoid arthritis (HERA) study.

OBJECTIVE: To assess the longterm effect of delaying therapy with second-line agents in patients with early rheumatoid arthritis (RA). METHODS: One hundred nineteen patients who participated in a 9 month placebo controlled randomized trial of hydroxychloroquine sulfate (HCQ) were followed prospectively for an additional 3 years. Those randomized to HCQ are referred to as the early treatment group and those randomized to placebo as the delayed treatment group. Participants were assessed annually for pain [Arthritis Impact Measurement Scales (AIMS) and Stanford Health Assessment Questionnaire (HAQ)], physical disability (AIMS and HAQ), and the RA global well being scale (AIMS). Conversion of results into standard deviation (SD) units permitted defining a substantial difference as per Felson as > 0.30 SD units and a clinically indistinguishable difference as < or = 0.06 SD units. RESULTS: One hundred fifteen patients (97%) participated and complete data were available on 104 (87%). Compared to the early treatment group, the delayed group remained worse for both the pain and the physical disability outcomes over the additional 3 year followup. The difference in the RA global well being score became clinically indistinguishable for the early and delayed groups only after the 2 year post-trial assessment. The between-group differences were not explained by post-trial therapy with corticosteroids, other second-line agents, or nonsteroidal antiinflammatory drugs and analgesic preparations. CONCLUSION: These findings show that a delay in instituting therapy with second-line agents, even a 9 month delay in instituting a moderately powerful second-line agent such as HCQ, has significant effects on longterm patient outcome, and provides strong evidence in support of early therapy in RA.

Adult↗
PubMed1999

Sensitivity of the Systemic Lupus Erythematosus Disease Activity Index, British Isles Lupus Assessment Group Index, and Systemic Lupus Activity Measure in the evaluation of clinical change in childhood-onset systemic lupus erythematosus.

OBJECTIVE: To investigate whether 3 disease activity indices commonly used to evaluate systemic lupus erythematosus (SLE) in adults are sensitive to clinical change in children, and thus suitable for the use in the management of childhood-onset SLE. METHODS: Thirty-five SLE patients who were newly diagnosed between 1993 and 1997, had an age at onset of 6-16 years (26 female and 9 male), and were currently being followed up at The Hospital for Sick Children (followup of 9 months to 4 years) were reviewed. The SLEDAI (Systemic Lupus Erythematosus Disease Activity Index), BILAG (British Isles Lupus Assessment Group index), and SLAM (Systemic Lupus Activity Measure) were applied at up to 4 occasions during the disease course: at the time of diagnosis, 6 months postdiagnosis, at the time of a flare (a deterioration in clinical presentation or laboratory results requiring initiation or increase of either corticosteroids or "second-line" drugs), and 6 months postflare. The sensitivity of the 3 measures to change, as gauged by the effect size (ES), effect size index (ESI), standard response mean (SRM), responsiveness statistic (RS), and relative efficiency index (REI), were compared. RESULTS: All 3 tools were very sensitive to change in disease activity (ES >0.8, ESI >2.3, SRM >0.6, RS >0.86, REI >0.72), but were ranked differently depending on the statistic used for comparison. CONCLUSION: All 3 measures of disease activity are highly sensitive to clinical change in children; none showed an overall superiority. The SLEDAI, BILAG, and SLAM can all be used to study response to treatment in children with SLE.

Adult↗