Chelation Therapy for Intermittent Claudication and Coronary Heart Disease

Use a structured format…………………………………………………………… Y N NA N N Y Describe Objectives The clinical question explicitly……………………………………………………. Y N NA Y Y Y Data sources The databases (ie, list) and other information sources……………………….. Y N NA N N Y Review methods The selection criteria (ie, population, intervention, outcome, and study design); methods for validity assessment, data abstraction, and study characteristics, and quantitative data synthesis in sufficient detail to permit replication……. Y N NA Y N Y Results Characteristics of the RCTs included and excluded; qualitative and quantitative findings (ie, point estimates and confidence intervals); and subgroup analyses N N NA N I Y Conclusion The main results……………………………………………………………………. Y Y NA Y Y Y _________ Describe Introduction The explicit clinical problem, biological rationale for the intervention, and rationale for review ………………………………………………………………… Y Y Y Y Y Y Describe Methods Searching The information sources, in detail (e.g., databases, registers, personal files, expert informants, agencies, hand-searching), and any restrictions (years considered, publication status,l anguage of publication)…………………….. Y I Y N N Y Selection The inclusion and exclusion criteria (defining population, intervention, principal outcomes, and study design Validity assessment The criteria and process used (e.g., masked conditions, quality assessment, and their findings )…… N N Y N Y٭ Y٭ Data abstraction The process or processes used (completed independently, in duplicate) N N N N N N Study The type of study design, participants’ characteristics, details of intervention, characteristics outcome definitions, &c, and how clinical heterogeneity was assessed……….. Y N Y N Y Y Quantitative The principal measures of effect (e.g., relative risk), method of combining data synthesis results (statistical testing and confidence intervals), handling of missing data; how statistical heterogeneity was assessed; rationale for any a-priori sensitivity and subgroup analyses; and any assessment of publication bias…. NA NA NA NA NA NA Describe Results Trial flow Provide a meta-analysis profile summarising trial flow (see figure) …………… NA N NA NA NA NA Study Present descriptive data for each trial (e.g., age, sample size, intervention, Characteristics dose, duration, follow-up period) ………………………………………………. Y N Y Y Y Y Quantitative Report agreement on the selection and validity assessment; present simple data synthesis summary results (for each treatment group in each trial, for each primary outcome); present data needed to calculate effect sizes and confidence intervals in intention-to-treat analyses (e.g. 2x 2 tables of counts, means and SDs, proportions) …………………………………………………………………. I N I N Y Y Discussion Summarise key findings; discuss clinical inferences based on internal and external validity; interpret the results in light of the totality of available evidence; describe potential biases in the review process (e.g., publication bias); and suggest a future research agenda …………………………………. Y N Y Y Y Y G & M = Grier and Meyers, 1993; C & J = Chappell and Janson, 1996; E1 = Ernst 1997; El et al = Elihu et al, 1998; Olm = Olmstead 1998; E2 = Ernst 2000. † Only in Ernst 1997 and Ernst 2000 was the body of the text formally subdivided into Introduction, Methods, Results and Discussion sections; Elihu et al, 1998 and Olmstead, 1998 lacked an Abstract; for the latter review the summary sections 5.1.4 and 5.2.7 were taken to be equivalent for an Abstract. * These reviews included all types of studies. Some Descriptors in the QUORUM table have multiple elements, with respect to these Y = all or nearly all elements reported in the review; N = none or very few of the elements reported in the review; I = incomplete i.e. some elements only reported in the review. NA = not applicable. 6.3.3 Results of Reviews and analysis of Review Quality by additional criteria 6.3.3.1 General considerations The individual reviews were assessed according to whether statements were matched by references given in their support and whether statements were errors, misrepresentations or Chelation Therapy for Intermittent Claudication and Coronary Heart Disease 42 unsubstantiated by evidence quoted in their support. Also we examined the reviews for the direction and strength of their conclusions. The studies that were considered by the assessed reviews are shown in the table below. Table 19. Studies considered in reviews of chelation therapy STUDIES CONSIDERED IN REVIEWS Kitchell et al. ‡ Olszewer et al. SlothNielson et al.‡‡ Guldager et al. Van Rij et al. Hopf et al. Knudtson et al.† Uncontrolled studies. REVIEW DATE 1963 199