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Terry P Klassen

Publications and source records attributed to Terry P Klassen.

At least 19 recordsLinked to original sources
PubMed2006

Treatment in the pediatric emergency department is evidence based: a retrospective analysis.

BACKGROUND: Our goal was to quantify the evidence that is available to the physicians of a pediatric emergency department (PED) in making treatment decisions. Further, we wished to ascertain what percentage of evidence for treatment provided in the PED comes from pediatric studies. METHODS: We conducted a retrospective chart review of randomly selected patients seen in the PED between January 1 and December 31, 2002. The principal investigator identified a primary diagnosis and primary intervention for each chart. A thorough literature search was then undertaken with respect to the primary intervention. If a randomized control trial (RCT) or a systematic review was found, the intervention was classified as level I evidence. If no RCT was found, the intervention was assessed by an expert committee who determined its appropriateness based on face validity (RCTs were unanimously judged to be both unnecessary and, if a placebo would have been involved, unethical). These interventions were classified as level II evidence. Interventions that did not fall into either above category were classified as level III evidence. RESULTS: Two hundred and sixty-two patient charts were reviewed. Of these, 35.9% did not receive a primary intervention. Of the 168 interventions assessed, 80.4% were evidence-based (level I), 7.1% had face validity (level II) and 12.5% had no supporting evidence (level III). Of the evidence-based interventions, 83.7% were supported by studies with mostly pediatric patients. CONCLUSION: Our study demonstrates that a substantial proportion of PED treatment decisions are evidence-based, with most based on studies in pediatric patients. Also, a large number of patients seen in the PED receive no intervention.

Child↗
PubMed2006

An alternative to the hand searching gold standard: validating methodological search filters using relative recall.

BACKGROUND: Search filters or hedges play an important role in evidence-based medicine but their development depends on the availability of a "gold standard"--a reference standard against which to establish the performance of the filter. We demonstrate the feasibility of using relative recall of included studies from multiple systematic reviews to validate methodological search filters as an alternative to validation against a gold standard formed through hand searching. METHODS: We identified 105 Cochrane reviews that used the Highly Sensitive Search Strategy (HSSS), included randomized or quasi-randomized controlled trials, and reported their included studies. We measured the ability of two published and one novel variant of the HSSS to retrieve the MEDLINE-index studies included in these reviews. RESULTS: The systematic reviews were comprehensive in their searches. 72% of included primary studies were indexed in MEDLINE. Relative recall of the three strategies ranged from .98 to .91 across all reviews and more comprehensive strategies showed higher recall. CONCLUSION: An approach using relative recall instead of a hand searching gold standard proved feasible and produced recall figures that were congruent with previously published figures for the HSSS. This technique would permit validation of a methodological filter using a collection of approximately 100 studies of the chosen design drawn from the included studies of multiple systematic reviews that used comprehensive search strategies.

Abstracting and Indexing↗
PubMed2006

Effects of exercise on breast cancer patients and survivors: a systematic review and meta-analysis.

BACKGROUND: Physical exercise has been identified as a potential intervention to improve quality of life in women with breast cancer. We sought to summarize the available evidence concerning the effects of exercise on breast cancer patients and survivors. METHODS: We searched the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, CINAHL, PsychINFO, CancerLit, PEDro and SportDiscus as well as conference proceedings, clinical practice guidelines and other unpublished literature resources. We included only randomized controlled trials that examined exercise interventions for breast cancer patients or survivors with quality of life, cardiorespiratory fitness or physical functioning as primary outcomes. We also extracted data on symptoms of fatigue, body composition and adverse effects. RESULTS: Of 136 studies identified, 14 met all the inclusion criteria. Despite significant heterogeneity and relatively small samples, the point estimates in terms of the benefits of exercise for all outcomes were positive even when statistical significance was not achieved. Exercise led to statistically significant improvements in quality of life as assessed by the Functional Assessment of Cancer Therapy-General (weighted mean difference [WMD] 4.58, 95% confidence interval [CI] 0.35 to 8.80) and Functional Assessment of Cancer Therapy-Breast (WMD 6.62, 95% CI 1.21 to 12.03). Exercise also led to significant improvements in physical functioning and peak oxygen consumption and in reducing symptoms of fatigue. INTERPRETATION: Exercise is an effective intervention to improve quality of life, cardiorespiratory fitness, physical functioning and fatigue in breast cancer patients and survivors. Larger trials that have a greater focus on study quality and adverse effects and that examine the long-term benefits of exercise are needed for this patient group.

Breast Neoplasms↗
PubMed2006

A cluster randomized controlled trial comparing three methods of disseminating practice guidelines for children with croup [ISRCTN73394937].

BACKGROUND: The optimal management of croup--a common respiratory illness in young children--is well established. In particular, treatment with corticosteroids has been shown to significantly reduce the rate and duration of intubation, hospitalization, and return to care for on-going croup symptoms. Furthermore treatment with a single dose of corticosteroids does not appear to result in any significant adverse outcomes, and yields overall cost-savings for both families and the health care system. However, as has been shown with many other diseases, there is a significant gap between what we know and what we do. The overall aim of this study is to identify, from a societal perspective, the costs and associated benefits of three strategies for implementing a practice guideline that addresses the management of croup. METHODS/DESIGNS: We propose to use a matched pair cluster trial in 24 Alberta hospitals randomized into three intervention groups. We will use mixed methods to assess outcomes including linkage and analysis of administrative databases obtained from Alberta Health and Wellness, retrospective medical chart audit, and prospective telephone surveys of the parents of children diagnosed to have croup. The intervention strategies to be compared will be mailing of printed educational materials (low intensity intervention), mailing plus a combination of interactive educational meetings, educational outreach visits, and reminders (intermediate intensity intervention), and a combination of mailing, interactive sessions, outreach visits, reminders plus identification of local opinion leaders and establishment of local consensus processes (high intensity intervention). The primary objective is to determine which of the three intervention strategies are most effective at lowering the rate of hospital days per 1,000 disease episodes. Secondary objectives are to determine which of the three dissemination strategies are most effective at increasing the use of therapies of known benefit. An economic analysis will be conducted to determine which of the three intervention strategies will most effectively reduce total societal costs including all health care costs, costs borne by the family, and costs stemming from the strategies for disseminating guidelines.

Journal Article↗
PubMed2006

Single data extraction generated more errors than double data extraction in systematic reviews.

BACKGROUND AND OBJECTIVE: To conduct a pilot study to compare the frequency of errors that accompany single vs. double data extraction, compare the estimate of treatment effect derived from these methods, and compare the time requirements for these methods. METHODS: Reviewers were randomized to the role of data extractor or data verifier, and were blind to the study hypothesis. The frequency of errors associated with each method of data extraction was compared using the McNemar test. The data set for each method was used to calculate an efficacy estimate by each method, using standard meta-analytic techniques. The time requirement for each method was compared using a paired t-test. RESULTS: Single data extraction resulted in more errors than double data extraction (relative difference: 21.7%, P = .019). There was no substantial difference between methods in effect estimates for most outcomes. The average time spent for single data extraction was less than the average time for double data extraction (relative difference: 36.1%, P = .003). CONCLUSION: In the case that single data extraction is used in systematic reviews, reviewers and readers need to be mindful of the possibility for more errors and the potential impact these errors may have on effect estimates.

Data Interpretation, Statistical↗
PubMed2006

Can electronic search engines optimize screening of search results in systematic reviews: an empirical study.

BACKGROUND: Most electronic search efforts directed at identifying primary studies for inclusion in systematic reviews rely on the optimal Boolean search features of search interfaces such as DIALOG and Ovid. Our objective is to test the ability of an Ultraseek search engine to rank MEDLINE records of the included studies of Cochrane reviews within the top half of all the records retrieved by the Boolean MEDLINE search used by the reviewers. METHODS: Collections were created using the MEDLINE bibliographic records of included and excluded studies listed in the review and all records retrieved by the MEDLINE search. Records were converted to individual HTML files. Collections of records were indexed and searched through a statistical search engine, Ultraseek, using review-specific search terms. Our data sources, systematic reviews published in the Cochrane library, were included if they reported using at least one phase of the Cochrane Highly Sensitive Search Strategy (HSSS), provided citations for both included and excluded studies and conducted a meta-analysis using a binary outcome measure. Reviews were selected if they yielded between 1000-6000 records when the MEDLINE search strategy was replicated. RESULTS: Nine Cochrane reviews were included. Included studies within the Cochrane reviews were found within the first 500 retrieved studies more often than would be expected by chance. Across all reviews, recall of included studies into the top 500 was 0.70. There was no statistically significant difference in ranking when comparing included studies with just the subset of excluded studies listed as excluded in the published review. CONCLUSION: The relevance ranking provided by the search engine was better than expected by chance and shows promise for the preliminary evaluation of large results from Boolean searches. A statistical search engine does not appear to be able to make fine discriminations concerning the relevance of bibliographic records that have been pre-screened by systematic reviewers.

Abstracting and Indexing↗
PubMed2006

Efficacy and safety of exogenous melatonin for secondary sleep disorders and sleep disorders accompanying sleep restriction: meta-analysis.

OBJECTIVE: To conduct a systematic review of the efficacy and safety of exogenous melatonin in managing secondary sleep disorders and sleep disorders accompanying sleep restriction, such as jet lag and shiftwork disorder. DATA SOURCES: 13 electronic databases and reference lists of relevant reviews and included studies; Associated Professional Sleep Society abstracts (1999 to 2003). STUDY SELECTION: The efficacy review included randomised controlled trials; the safety review included randomised and non-randomised controlled trials. QUALITY ASSESSMENT: Randomised controlled trials were assessed by using the Jadad Scale and criteria by Schulz et al, and non-randomised controlled trials by the Downs and Black checklist. DATA EXTRACTION AND SYNTHESIS: One reviewer extracted data and another reviewer verified the data extracted. The inverse variance method was used to weight studies and the random effects model was used to analyse data. MAIN RESULTS: Six randomised controlled trials with 97 participants showed no evidence that melatonin had an effect on sleep onset latency in people with secondary sleep disorders (weighted mean difference -13.2 (95% confidence interval -27.3 to 0.9) min). Nine randomised controlled trials with 427 participants showed no evidence that melatonin had an effect on sleep onset latency in people who had sleep disorders accompanying sleep restriction (-1.0 (-2.3 to 0.3) min). 17 randomised controlled trials with 651 participants showed no evidence of adverse effects of melatonin with short term use (three months or less). CONCLUSIONS: There is no evidence that melatonin is effective in treating secondary sleep disorders or sleep disorders accompanying sleep restriction, such as jet lag and shiftwork disorder. There is evidence that melatonin is safe with short term use.

Adolescent↗
PubMed2006

A systematic review identifies a lack of standardization in methods for handling missing variance data.

BACKGROUND AND OBJECTIVES: To describe and critically appraise available methods for handling missing variance data in meta-analysis (MA). METHODS: Systematic review. MEDLINE, EMBASE, Web of Science, MathSciNet, Current Index to Statistics, BMJ SearchAll, The Cochrane Library and Cochrance Colloquium proceedings, MA texts and references were searched. Any form of text was included: MA, method chapter, or otherwise. Descriptions of how to implement each method, the theoretic basis and/or ad hoc motivation(s), and the input and output variable(s) were extracted and assessed. Methods may be: true imputations, methods that obviate the need for a standard deviation (SD), or methods that recalculate the SD. RESULTS: Eight classes of methods were identified: algebraic recalculations, approximate algebraic recalculations, imputed study-level SDs, imputed study-level SDs from nonparametric summaries, imputed study-level correlations (e.g., for change-from-baseline SD), imputed MA-level effect sizes, MA-level tests, and no-impute methods. CONCLUSION: This work aggregates the ideas of many investigators. The abundance of methods suggests a lack of consistency within the systematic review community. Appropriate use of methods is sometimes suspect; consulting a statistician, early in the review process, is recommended. Further work is required to optimize method choice to alleviate any potential for bias and improve accuracy. Improved reporting is also encouraged.

Data Interpretation, Statistical↗
PubMed2005

Publication bias of randomized controlled trials in emergency medicine.

OBJECTIVES: To determine the publication status and time to publication of randomized controlled trials (RCTs) that were presented at the Society for Academic Emergency Medicine (SAEM) meetings from 1995 to 2003. The impact of positive-outcome bias, time-lag bias, and gray literature bias also was assessed. METHODS: Retrospective cohort study of RCT abstracts presented at nine SAEM scientific meetings. Electronic searches identified publications from the abstracts. RESULTS: Of 4,399 abstracts, 383 (8.7%; 95% confidence interval [CI] = 7.8% to 9.5%) were identified as RCTs. One hundred ninety-four (50.7%; 95% CI = 45.7% to 55.7%) were subsequently published up to May 2004. The median time to publication was 32 months (95% CI = 23 to 41), with 59% of RCT abstracts published within five years of presentation. No evidence of positive-outcome bias or time-lag bias was identified; however, changes from abstract to manuscript were found. Manuscripts were less likely to endorse the experimental intervention than were abstracts (OR, 0.2; 95% CI = 0.0 to 0.6). CONCLUSIONS: The proportion of emergency medicine RCT abstracts published is slightly lower than that for other biomedical specialties; however, biases reported by investigators in other biomedical areas do not appear to be as problematic in emergency medicine research. Differences between conclusions from abstracts and manuscripts must be considered when employing meeting abstracts as a source of evidence for future research or for systematic reviews in emergency medicine.

Abstracting and Indexing↗
PubMed2005

Children in reviews: methodological issues in child-relevant evidence syntheses.

BACKGROUND: The delivery of optimal medical care to children is dependent on the availability of child relevant research. Our objectives were to: i) systematically review and describe how children are handled in reviews of drug interventions published in the Cochrane Database of Systematic Reviews (CDSR); and ii) determine when effect sizes for the same drug interventions differ between children and adults. METHODS: We systematically identified all of the reviews relevant to child health in the CDSR 2002, Issue 4. Reviews were included if they investigated the efficacy or effectiveness of a drug intervention for a condition that occurs in both children and adults. Information was extracted on review characteristics including study methods, results, and conclusions. RESULTS: From 1496 systematic reviews, 408 (27%) were identified as relevant to both adult and child health; 52% (213) of these included data from children. No significant differences were found in effect sizes between adults and children for any of the drug interventions or conditions investigated. However, all of the comparisons lacked the power to detect a clinically significant difference and wide confidence intervals suggest important differences cannot be excluded. A large amount of data was unavailable due to inadequate reporting at the trial and systematic review level. CONCLUSION: Overall, the findings of this study indicate there is a paucity of child-relevant and specific evidence generated from evidence syntheses of drug interventions. The results indicate a need for a higher standard of reporting for participant populations in studies of drug interventions.

Adolescent↗
PubMed2005

Which resources should be used to identify RCT/CCTs for systematic reviews: a systematic review.

BACKGROUND: Systematic reviewers seek to comprehensively search for relevant studies and summarize these to present the most valid estimate of intervention effectiveness. The more resources searched, the higher the yield, and thus time and costs required to conduct a systematic review. While there is an abundance of evidence to suggest how extensive a search for randomized controlled trials (RCTs) should be, it is neither conclusive nor consistent. This systematic review was conducted in order to assess the value of different resources to identify trials for inclusion in systematic reviews. METHODS: Seven electronic databases, four journals and Cochrane Colloquia were searched. Key authors were contacted and references of relevant articles screened. Included studies compared two or more sources to find RCTs or controlled clinical trials (CCTs). A checklist was developed and applied to assess quality of reporting. Data were extracted by one reviewer and checked by a second. Medians and ranges for precision and recall were calculated; results were grouped by comparison. Meta-analysis was not performed due to large heterogeneity. Subgroup analyses were conducted for: search strategy (Cochrane, Simple, Complex, Index), expertise of the searcher (Cochrane, librarian, non-librarian), and study design (RCT and CCT). RESULTS: Sixty-four studies representing 13 electronic databases met inclusion criteria. The most common comparisons were MEDLINE vs. handsearching (n = 23), MEDLINE vs. MEDLINE+handsearching (n = 13), and MEDLINE vs. reference standard (n = 13). Quality was low, particularly for the reporting of study selection methodology. Overall, recall and precision varied substantially by comparison and ranged from 0 to 100% and 0 to 99%, respectively. The trial registries performed the best with median recall of 89% (range 84, 95) and median precision of 96.5% (96, 97), although these results are based on a small number of studies. Inadequate or inappropriate indexing was the reason most cited for missing studies. Complex and Cochrane search strategies (SS) performed better than Simple SS. CONCLUSION: Multiple-source comprehensive searches are necessary to identify all RCTs for a systematic review, although indexing needs to be improved. Although trial registries demonstrated the highest recall and precision, the Cochrane SS or a Complex SS in consultation with a librarian are recommended. Continued efforts to develop CENTRAL should be supported.

Databases, Bibliographic↗
PubMed2005

Challenges in systematic reviews of therapeutic devices and procedures.

The authors discuss 3 challenges in conducting and interpreting any systematic review that are particularly relevant for systematic reviews of therapeutic devices or surgical procedures: 1) inclusion or exclusion of grey literature, 2) the role of nonrandomized studies, and 3) issues in applying the results to clinical care that are unique to the surgical and therapeutic device literature. The authors also discuss empirical evidence related to these topics and illustrate how reviewers in the Agency for Healthcare Research and Quality's Evidence-based Practice Center program have dealt with these challenges in developing evidence reports for decision makers and clinicians about therapeutic devices or surgical procedures.

Clinical Trials as Topic↗
PubMed2005

A systematic review of intravenous gamma globulin for therapy of acute myocarditis.

BACKGROUND: Intravenous gamma globulin (IVGG) is commonly used in the management of acute myocarditis. The objective of this study was to systematically review the literature evaluating this practice. METHODS: We conducted a comprehensive search (electronic databases, trials registries, conference proceedings, reference lists, contact with authors) to identify studies evaluating the use of IVGG in adults and children with a clinical or histologically proven diagnosis of myocarditis of possible viral etiology and symptoms of less than six months duration. Two reviewers independently screened the searches, applied inclusion criteria, and graded the evidence. RESULTS: Results were described qualitatively; data were not pooled because only one randomized controlled trial (RCT) with 62 patients was identified. The RCT showed no benefit with respect to cardiac function, functional outcome, or event-free survival. A small, uncontrolled trial (n = 10) showed significant improvement in LVEF from a mean of 24% to 41% 12 months after IVGG in nine survivors. A retrospective cohort study of pediatric patients showed improvement in cardiac function and a trend towards improved survival in patients receiving IVGG (n = 21) versus historic controls (n = 25). Ten case reports and two case series (total n = 21) described improvement in cardiac function after administration of IVGG; two case reports showed no benefit of IVGG. One case of hemolytic anemia was attributed to IVGG. CONCLUSION: There is insufficient data from methodologically strong studies to recommend routine use of IVGG for acute myocarditis. Future randomized studies that take into account the etiology of acute myocarditis will be required to determine the efficacy of IVGG.

Acute Disease↗
PubMed2005

Effectiveness of a home-based balance-training program in reducing sports-related injuries among healthy adolescents: a cluster randomized controlled trial.

BACKGROUND: Sport is the leading cause of injury requiring medical attention among adolescents. We studied the effectiveness of a home-based balance-training program using a wobble board in improving static and dynamic balance and reducing sports-related injuries among healthy adolescents. METHODS: In this cluster randomized controlled trial, we randomly selected 10 of 15 high schools in Calgary to participate in the fall of 2001. We then recruited students from physical education classes and randomly assigned them, by school, to either the intervention (n = 66) or the control (n = 61) group. Students in the intervention group participated in a daily 6-week and then a weekly 6-month home-based balance-training program using a wobble board. Students at the control schools received testing only. The primary outcome measures were timed static and dynamic balance, 20-m shuttle run and vertical jump, which were measured at baseline and biweekly for 6 weeks. Self-reported injury data were collected over the 6-month follow-up period. RESULTS: At 6 weeks, improvements in static and dynamic balance were observed in the intervention group but not in the control group (difference in static balance 20.7 seconds, 95% confidence interval [CI] 10.8 to 30.6 seconds; difference in dynamic balance 2.3 seconds, 95% CI 0.7 to 4.0 seconds). There was evidence of a protective effect of balance training in over 6 months (relative risk of injury 0.2, 95% CI 0.05 to 0.88). The number needed to treat to avoid 1 injury over 6 months was 8 (95% CI 4 to 35). INTERPRETATION: Balance training using a wobble board is effective in improving static and dynamic balance and reducing sports-related injuries among healthy adolescents.

Adolescent↗
PubMed2005

A randomized, double-blind, placebo-controlled noninferiority trial of amoxicillin for clinically diagnosed acute otitis media in children 6 months to 5 years of age.

OBJECTIVES: Debate continues with respect to a "watch and wait" approach versus immediate antibiotic treatment for the initial treatment of acute otitis media. In this double-blind noninferiority trial, we compared clinical improvement rates at 14 days for children (6 months to 5 years of age) with acute otitis media who were randomly assigned to receive amoxicillin or placebo. METHODS: We enrolled healthy children who presented to clinics or the emergency department with a new episode of acute otitis media during the fall and winter months in Ottawa (from December 1999 to the end of March 2002). The children were randomly assigned to receive amoxicillin (60 mg/kg daily) or placebo for 10 days. Telephone follow-up was performed on each of days 1, 2 and 3 and once between day 10 and day 14. The primary outcome was clinical resolution of symptoms, defined as absence of receipt of an antimicrobial (other than the amoxicillin in the treatment group) at any time during the 14-day period. Secondary outcomes were the presence of pain and fever and the activity level in the first 3 days, recurrence rates, and the presence of middle ear effusion at 1 and 3 months. RESULTS: According to clinical scoring, 415 of the 512 children who could be evaluated had moderate disease. At 14 days 84.2% of the children receiving placebo and 92.8% of those receiving amoxicillin had clinical resolution of symptoms (absolute difference -8.6%, 95% confidence interval -14.4% to -3.0%). Children who received placebo had more pain and fever in the first 2 days. There were no statistical differences in adverse events between the 2 groups, nor were there any significant differences in recurrence rates or middle ear effusion at 1 and 3 months. INTERPRETATION: Our results did not support the hypothesis that placebo was noninferior to amoxicillin (i.e., that the 14-day cure rates among children with clinically diagnosed acute otitis media would not be substantially worse in the placebo group than the treatment group). Nevertheless, delaying treatment was associated with resolution of clinical signs and symptoms in most of the children.

Acute Disease↗
PubMed2005

For randomized controlled trials, the quality of reports of complementary and alternative medicine was as good as reports of conventional medicine.

OBJECTIVE: To compare the quality of reporting of reports randomized controlled trials (RCTs) published in English and in languages other than English (LOE), and to determine whether there were differences between conventional medicine (CM) and complementary and alternative medicine (CAM) reports. STUDY DESIGN AND SETTING: We examined more than 600 RCTs associated with 125 systematic reviews. We extracted characteristics of each RCT using a standardized data collection form. We assessed quality using the Jadad scale and the adequacy of allocation concealment. RESULTS: There were only minor differences in the quality of reports of RCTs published in English compared with other languages (median quality score of 3 vs. 2, P=.10), and the quality of reports of CAM RCTs was similar to the CM reports (median score of 3 vs. 2, P=.14). There was no effect of language of publication on quality of reporting for CM trials (median score of 2 vs. 2, P=.12). Among CAM trials, however, overall quality scores were higher for reports in English than for reports in other languages (median score of 3 vs. 2, P=.04). CONCLUSION: The overall quality of reports published in languages other than English is similar to that of English-language reports. Moreover, the overall quality of reporting of RCTs of CAM interventions is as good as that for CM interventions.

Bibliometrics↗
PubMed2005

Language of publication restrictions in systematic reviews gave different results depending on whether the intervention was conventional or complementary.

OBJECTIVE: To assess whether language of publication restrictions impact the estimates of an intervention's effectiveness, whether such impact is similar for conventional medicine and complementary medicine interventions, and whether the results are influenced by publication bias and statistical heterogeneity. STUDY DESIGN AND SETTING: We set out to examine the extent to which including reports of randomized controlled trials (RCTs) in languages other than English (LOE) influences the results of systematic reviews, using a broad dataset of 42 language-inclusive systematic reviews, involving 662 RCTs, including both conventional medicine (CM) and complementary and alternative medicine (CAM) interventions. RESULTS: For CM interventions, language-restricted systematic reviews, compared with language-inclusive ones, did not introduce biased results, in terms of estimates of intervention effectiveness (random effects ration of odds rations ROR=1.02; 95% CI=0.83-1.26). For CAM interventions, however, language-restricted systematic reviews resulted in a 63% smaller protective effect estimate than language-inclusive reviews (random effects ROR=1.63; 95% CI=1.03-2.60). CONCLUSION: Language restrictions do not change the results of CM systematic reviews but do substantially alter the results of CAM systematic reviews. These findings are robust even after sensitivity analyses, and do not appear to be influenced by statistical heterogeneity and publication bias.

Complementary Therapies↗