Gerben ter Riet

Accuracy of Ottawa ankle rules to exclude fractures of the ankle and mid-foot: systematic review

Abstract Objective: To summarise the evidence on accuracy of the Ottawa ankle rules, a decision aid for excluding fractures of the ankle and mid-foot. Design: Systematic review. Data sources: Electronic databases, reference lists of included studies, and experts. Review methods: Data were extracted on the study population, the type of Ottawa ankle rules used, and methods. Sensitivities, but not specificities, were pooled using the bootstrap after inspection of the receiver operating characteristics plot. Negative likelihood ratios were pooled for several subgroups, correcting for four main methodological threats to validity. Results: 32 studies met the inclusion criteria and 27 studies reporting on 15 581 patients were used for meta-analysis. The pooled negative likelihood ratios for the ankle and mid-foot were 0.08 (95% confidence interval 0.03 to 0.18) and 0.08 (0.03 to 0.20), respectively. The pooled negative likelihood ratio for both regions in children was 0.07 (0.03 to 0.18). Applying these ratios to a 15% prevalence of fracture gave a less than 1.4% probability of actual fracture in these subgroups. Conclusion: Evidence supports the Ottawa ankle rules as an accurate instrument for excluding fractures of the ankle and mid-foot. The instrument has a sensitivity of almost 100% and a modest specificity, and its use should reduce the number of unnecessary radiographs by 30-40%. What is already known on this topic Although most patients with ankle sprains who present to emergency departments undergo radiography, less than 15% have a fracture The Ottawa ankle rules is a clinical decision aid designed to avoid unnecessary radiography What this paper adds The Ottawa ankle rules is highly accurate at excluding ankle fractures after sprain injury

Accuracy of mean arterial pressure and blood pressure measurements in predicting pre-eclampsia: systematic review and meta-analysis

Objective To determine the accuracy of using systolic and diastolic blood pressure, mean arterial pressure, and increase of blood pressure to predict pre-eclampsia. Design Systematic review with meta-analysis of data on test accuracy. Data sources Medline, Embase, Cochrane Library, Medion, checking reference lists of included articles and reviews, contact with authors. Review methods Without language restrictions, two reviewers independently selected the articles in which the accuracy of blood pressure measurement during pregnancy was evaluated to predict pre-eclampsia. Data were extracted on study characteristics, quality, and results to construct 2×2 tables. Summary receiver operating characteristic curves and likelihood ratios were generated for the various levels and their thresholds. Results 34 studies, testing 60 599 women (3341 cases of pre-eclampsia), were included. In women at low risk for pre-eclampsia, the areas under the summary receiver operating characteristic curves for blood pressure measurement in the second trimester were 0.68 (95% confidence interval 0.64 to 0.72) for systolic blood pressure, 0.66 (0.59 to 0.72) for diastolic blood pressure, and 0.76 (0.70 to 0.82) for mean arterial pressure. Findings for the first trimester showed a similar pattern. Second trimester mean arterial pressure of 90 mm Hg or more showed a positive likelihood ratio of 3.5 (95% confidence interval 2.0 to 5.0) and a negative likelihood ratio of 0.46 (0.16 to 0.75). In women deemed to be at high risk, a diastolic blood pressure of 75 mm Hg or more at 13 to 20 weeks’ gestation best predicted pre-eclampsia: positive likelihood ratio 2.8 (1.8 to 3.6), negative likelihood ratio 0.39 (0.18 to 0.71). Additional subgroup analyses did not show improved predictive accuracy. Conclusion When blood pressure is measured in the first or second trimester of pregnancy, the mean arterial pressure is a better predictor for pre-eclampsia than systolic blood pressure, diastolic blood pressure, or an increase of blood pressure.

Endometrial thickness measurement for detecting endometrial cancer in women with postmenopausal bleeding: a systematic review and meta-analysis

OBJECTIVE: To estimate the accuracy of endometrial thickness measurement in the detection of endometrial cancer among women with postmenopausal bleeding with individual patient data using different meta-analytic strategies. DATA SOURCES: Original data sets of studies detected after reviewing the included studies of three previous reviews on this subject. An additional literature search of published articles using MEDLINE databases was preformed from January 2000 to December 2006 to identify articles reporting on endometrial carcinoma and sonographic endometrial thickness measurement in women with postmenopausal bleeding. METHODS OF STUDY SELECTION: We identified 90 studies reporting on endometrial thickness measurements and endometrial carcinoma in women with postmenopausal bleeding. TABULATION, INTEGRATION, AND RESULTS: We contacted 79 primary investigators to obtain the individual patient data of their reported studies, of which 13 could provide data. Data on 2,896 patients, of which 259 had carcinoma, were included. Several approaches were used in the analyses of the acquired data. First, we performed receiver operator characteristics (ROC) analysis per study, resulting in a summary area under the ROC curve (AUC) calculated as a weighted mean of AUCs from original studies. Second, individual patient data were pooled and analyzed with ROC analyses irrespective of study with standardization of distributional differences across studies using multiples of the median and by random effects logistic regression. Finally, we also used a two-stage procedure, calculating sensitivities and specificities for each study and using the bivariate random effects model to estimate summary estimates for diagnostic accuracy. This resulted in rather comparable ROC curves with AUCs varying between 0.82 and 0.84 and summary estimates for sensitivity and specificity located along these curves. These curves indicated a lower AUC than previously reported meta-analyses using conventional techniques. CONCLUSION: Previous meta-analyses on endometrial thickness measurement probably have overestimated its diagnostic accuracy in the detection of endometrial carcinoma. We advise the use of cutoff level of 3 mm for exclusion of endometrial carcinoma in women with postmenopausal bleeding.

Cranberries vs antibiotics to prevent urinary tract infections: a randomized double-blind noninferiority trial in premenopausal women

BACKGROUND The increasing prevalence of uropathogens resistant to antimicrobial agents has stimulated interest in cranberries to prevent recurrent urinary tract infections (UTIs). METHODS In a double-blind, double-dummy noninferiority trial, 221 premenopausal women with recurrent UTIs were randomized to 12-month prophylaxis use of trimethoprim-sulfamethoxazole (TMP-SMX), 480 mg once daily, or cranberry capsules, 500 mg twice daily. Primary end points were the mean number of symptomatic UTIs over 12 months, the proportion of patients with at least 1 symptomatic UTI, the median time to first UTI, and development of antibiotic resistance in indigenous Escherichia coli. RESULTS After 12 months, the mean number of patients with at least 1 symptomatic UTI was higher in the cranberry than in the TMP-SMX group (4.0 vs 1.8; P = .02), and the proportion of patients with at least 1 symptomatic UTI was higher in the cranberry than in the TMP-SMX group (78.2% vs 71.1%). Median time to the first symptomatic UTI was 4 months for the cranberry and 8 months for the TMP-SMX group. After 1 month, in the cranberry group, 23.7% of fecal and 28.1% of asymptomatic bacteriuria E coli isolates were TMP-SMX resistant, whereas in the TMP-SMX group, 86.3% of fecal and 90.5% of asymptomatic bacteriuria E coli isolates were TMP-SMX resistant. Similarly, we found increased resistance rates for trimethoprim, amoxicillin, and ciprofloxacin in these E coli isolates after 1 month in the TMP-SMX group. After discontinuation of TMP-SMX, resistance reached baseline levels after 3 months. Antibiotic resistance did not increase in the cranberry group. Cranberries and TMP-SMX were equally well tolerated. CONCLUSION In premenopausal women, TMP-SMX, 480 mg once daily, is more effective than cranberry capsules, 500 mg twice daily, to prevent recurrent UTIs, at the expense of emerging antibiotic resistance. TRIAL REGISTRATION isrctn.org Identifier: ISRCTN50717094.

Systematic reviews of complementary therapies – an annotated bibliography. Part 3: Homeopathy

BackgroundComplementary therapies are widespread but controversial. We aim to provide a comprehensive collection and a summary of systematic reviews of clinical trials in three major complementary therapies (acupuncture, herbal medicine, homeopathy). This article is dealing with homeopathy. Potentially relevant reviews were searched through the register of the Cochrane Complementary Medicine Field, the Cochrane Library, Medline, and bibliographies of articles and books. To be included articles had to review prospective clinical trials of homeopathy; had to describe review methods explicitly; had to be published; and had to focus on treatment effects. Information on conditions, interventions, methods, results and conclusions was extracted using a pretested form and summarized descriptively.ResultsEighteen out of 22 potentially relevant reviews preselected in the screening process met the inclusion criteria. Six reviews addressed the question whether homeopathy is effective across conditions and interventions. The majority of available trials seem to report positive results but the evidence is not convincing. For isopathic nosodes for allergic conditions, oscillococcinum for influenza-like syndromes and galphimia for pollinosis the evidence is promising while in other areas reviewed the results are equivocal.InterpretationReviews on homeopathy often address general questions. While the evidence is promising for some topics the findings of the available reviews are unlikely to end the controversy on this therapy.

Randomized clinical trial of ascorbic acid in the treatment of pressure ulcers

The objective of this study was to assess the effects of ascorbic acid supplementation, 500 mg twice daily in the treatment of pressure ulcers as an adjunct to standardized treatment. The design consisted of a multicenter blinded randomized trial. The control group received 10 mg of ascorbic acid twice daily. Patients from 11 nursing homes and 1 hospital participated. Main outcome measures included wound survival, healing rates of wound surfaces, and clinimetric changes over 12 weeks. Eighty-eight patients were randomized. Intention-to-treat analysis showed that the wound closure probability per unit time (i.e., the closure rate) was not higher in the intervention group than in the control group (Cox hazard ratio of 0.78 [90% precision interval, 0.44-1.39]). Mean absolute healing rates were 0.21 and 0.27 cm2/week in the intervention and control group, respectively (PI of the adjusted difference: -0.17 to 0.13). Relative healing rates and healing velocities did not show favorable results of ascorbic acid supplementation, either. A panel scored slides of the ulcers with a report mark between 1 (bad) and 10 (excellent). The improvement was 0.45 and 0.72 points per week in the intervention and control group, respectively (PI of the adjusted difference: -0.50 to 0.20). With another clinimetric index we could not show any differences, either. These data do not support the idea that ascorbic acid supplementation (500 vs. 10 mg twice daily) speeds up the healing of pressure ulcers.

Systematic reviews of complementary therapies - an annotated bibliography. Part 1: acupuncture

BackgroundComplementary therapies are widespread but controversial. We aim to provide a comprehensive collection and a summary of systematic reviews of clinical trials in three major complementary therapies (acupuncture, herbal medicine, homeopathy). This article is dealing with acupuncture. Potentially relevant reviews were searched through the register of the Cochrane Complementary Medicine Field, the Cochrane Library, Medline, and bibliographies of articles and books. To be included articles had to review prospective clinical trials of acupuncture; had to describe review methods explicitly; had to be published; and had to focus on treatment effects. Information on conditions, interventions, methods, results and conclusions was extracted using a pretested form and summarized descriptively.ResultsFrom a total of 48 potentially relevant reviews preselected in a screeening process 39 met the inclusion criteria. 22 were on various pain syndromes or rheumatic diseases. Other topics addressed by more than one review were addiction, nausea, asthma and tinnitus. Almost unanimously the reviews state that acupuncture trials include too few patients. Often included trials are heterogeneous regarding patients, interventions and outcome measures, are considered to have insufficient quality and contradictory results. Convincing evidence is available only for postoperative nausea, for which acupuncture appears to be of benefit, and smoking cessation, where acupuncture is no more effective than sham acupuncture.ConclusionsA large number of systematic reviews on acupuncture exists. What is most obvious from these reviews is the need for (the funding of) well-designed, larger clinical trials.

Sample sizes of studies on diagnostic accuracy: literature survey

Abstract Objectives To determine sample sizes in studies on diagnostic accuracy and the proportion of studies that report calculations of sample size. Design Literature survey. Data sources All issues of eight leading journals published in 2002. Methods Sample sizes, number of subgroup analyses, and how often studies reported calculations of sample size were extracted. Results 43 of 8999 articles were non-screening studies on diagnostic accuracy. The median sample size was 118 (interquartile range 71-350) and the median prevalence of the target condition was 43% (27-61%). The median number of patients with the target condition—needed to calculate a tests sensitivity—was 49 (28-91). The median number of patients without the target condition—needed to determine a tests specificity—was 76 (27-209). Two of the 43 studies (5%) reported a priori calculations of sample size. Twenty articles (47%) reported results for patient subgroups. The number of subgroups ranged from two to 19 (median four). No studies reported that sample size was calculated on the basis of preplanned analyses of subgroups. Conclusion Few studies on diagnostic accuracy report considerations of sample size. The number of participants in most studies on diagnostic accuracy is probably too small to analyse variability of measures of accuracy across patient subgroups.

Lactobacilli vs Antibiotics to Prevent Urinary Tract Infections: A Randomized, Double-blind, Noninferiority Trial in Postmenopausal Women

BACKGROUND Growing antibiotic resistance warrants studying nonantibiotic prophylaxis for recurrent urinary tract infections (UTIs). Use of lactobacilli appears to be promising. METHODS Between January 2005 and August 2007, we randomized 252 postmenopausal women with recurrent UTIs taking part in a double-blind noninferiority trial to receive 12 months of prophylaxis with trimethoprim-sulfamethoxazole, 480 mg, once daily or oral capsules containing 109 colony-forming units of Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14 twice daily. Primary end points were the mean number of symptomatic UTIs, proportion of participants with at least 1 UTI during 12 months, time to first UTI, and development of antibiotic resistance by Escherichia coli. RESULTS The mean number of symptomatic UTIs in the year preceding randomization was 7.0 in the trimethoprim-sulfamethoxazole group and 6.8 in the lactobacilli group. In the intention-to-treat analysis, after 12 months of prophylaxis, these numbers were 2.9 and 3.3, respectively. The between-treatment difference of 0.4 UTIs per year (95% CI, -0.4 to 1.5) was outside our noninferiority margin. At least 1 symptomatic UTI occurred in 69.3% and 79.1% of the trimethoprim-sulfamethoxazole and lactobacilli participants, respectively; median times to the first UTI were 6 and 3 months, respectively. After 1 month of trimethoprim-sulfamethoxazole prophylaxis, resistance to trimethoprim-sulfamethoxazole, trimethoprim, and amoxicillin had increased from approximately 20% to 40% to approximately 80% to 95% in E coli from the feces and urine of asymptomatic women and among E coli causing a UTI. During the 3 months after trimethoprim-sulfamethoxazole discontinuation, resistance levels gradually decreased. Resistance did not increase during lactobacilli prophylaxis. CONCLUSIONS In postmenopausal women with recurrent UTIs, L rhamnosus GR-1 and L reuteri RC-14 do not meet the noninferiority criteria in the prevention of UTIs when compared with trimethoprim-sulfamethoxazole. However, unlike trimethoprim-sulfamethoxazole, lactobacilli do not increase antibiotic resistance. TRIAL REGISTRATION isrctn.org Identifier: ISRCTN50717094.

Is placebo analgesia mediated by endogenous opioids? A systematic review.

&NA; This systematic review assesses six experimental studies into the mechanism of placebo analgesia in human subjects suffering from clinical pain or experimentally induced ischaemic arm pain. Due to their sophisticated designs, these studies probably provide the best evidence that placebo analgesia exists. They also indicate that placebo analgesia is mediated by endogenous opiates. However, there seems to be room for additional studies.