Systematic reviews and meta-analyses of test accuracy studies are increasingly being recognised as central in guiding clinical practice. However, there is currently no dedicated and comprehensive software for meta-analysis of diagnostic data. In this article, we present Meta-DiSc, a Windows-based, user-friendly, freely available (for academic use) software that we have developed, piloted, and validated to perform diagnostic meta-analysis. Meta-DiSc a) allows exploration of heterogeneity, with a variety of statistics including chi-square, I-squared and Spearman correlation tests, b) implements meta-regression techniques to explore the relationships between study characteristics and accuracy estimates, c) performs statistical pooling of sensitivities, specificities, likelihood ratios and diagnostic odds ratios using fixed and random effects models, both overall and in subgroups and d) produces high quality figures, including forest plots and summary receiver operating characteristic curves that can be exported for use in manuscripts for publication. All computational algorithms have been validated through comparison with different statistical tools and published meta-analyses. Meta-DiSc has a Graphical User Interface with roll-down menus, dialog boxes, and online help facilities. Meta-DiSc is a comprehensive and dedicated test accuracy meta-analysis software. It has already been used and cited in several meta-analyses published in high-ranking journals. The software is publicly available at http://www.hrc.es/investigacion/metadisc_en.htm .

Background: Case-based learning (CBL) is a long established pedagogical method, which is defined in a number of ways depending on the discipline and type of ‘case’ employed. In health professional education, learning activities are commonly based on patient cases. Basic, social and clinical sciences are studied in relation to the case, are integrated with clinical presentations and conditions (including health and ill-health) and student learning is, therefore, associated with real-life situations. Although many claims are made for CBL as an effective learning and teaching method, very little evidence is quoted or generated to support these claims. We frame this review from the perspective of CBL as a type of inquiry-based learning. Aim: To explore, analyse and synthesise the evidence relating to the effectiveness of CBL as a means of achieving defined learning outcomes in health professional prequalification training programmes. Method: Selection criteria: We focused the review on CBL for prequalification health professional programmes including medicine, dentistry, veterinary science, nursing and midwifery, social care and the allied health professions (physiotherapy, occupational therapy, etc.). Papers were required to have outcome data on effectiveness. Search strategies: The search covered the period from 1965 to week 4 September 2010 and the following databases: ASSIA, CINAHL, EMBASE, Education Research, Medline and Web of Knowledge (WoK). Two members of the topic review group (TRG) independently reviewed the 173 abstracts retrieved from Medline and compared findings. As there was good agreement on inclusion, one went onto review the WoK and ASSIA EndNote databases and the other the Embase, CINAHL and Education Research databases to decide on papers to submit for coding. Coding and data analysis: The TRG modified the standard best evidence medical education coding sheet to fit our research questions and assessed each paper for quality. After a preliminary reliability exercise, each full paper was read and graded by one reviewer with the papers scoring 3–5 (of 5) for strength of findings being read by a second reviewer. A summary of each completed coding form was entered into an Excel spread sheet. The type of data in the papers was not amenable to traditional meta-analysis because of the variability in interventions, information given, student numbers (and lack of) and timings. We, therefore, adopted a narrative synthesis method to compare, contrast, synthesise and interpret the data, working within a framework of inquiry-based learning. Results: The final number of coded papers for inclusion was 104. The TRG agreed that 23 papers would be classified as of higher quality and significance (22%). There was a wide diversity in the type, timing, number and length of exposure to cases and how cases were defined. Medicine was the most commonly included profession. Numbers of students taking part in CBL varied from below 50 to over 1000. The shortest interventions were two hours, and one case, whereas the longest was CBL through a whole year. Group sizes ranged from students working alone to over 30, with the majority between 2 and 15 students per group. The majority of studies involved single cohorts of students (61%), with 29% comparing multiple groups, 8% involving different year groups and 2% with historical controls. The outcomes evaluation was either carried out postintervention only (78 papers; 75%), preintervention and postintervention (23 papers; 22%) or during and postintervention (3 papers; <3%). Our analysis provided the basis for discussion of definitions of CBL, methods used and advocated, topics and learning outcomes and whether CBL is effective based on the evaluation data. Conclusion: Overwhelmingly, students enjoy CBL and think that it enhances their learning. The empirical data taken as a whole are inconclusive as to the effects on learning compared with other types of activity. Teachers enjoy CBL, partly because it engages, and is perceived to motivate, students. CBL seems to foster learning in small groups though whether this is the case delivery or the group learning effect is unclear.

Objective To examine concordance between treatment effects in animal experiments and clinical trials. Study design Systematic review. Data sources Medline, Embase, SIGLE, NTIS, Science Citation Index, CAB, BIOSIS. Study selection Animal studies for interventions with unambiguous evidence of a treatment effect (benefit or harm) in clinical trials: head injury, antifibrinolytics in haemorrhage, thrombolysis in acute ischaemic stroke, tirilazad in acute ischaemic stroke, antenatal corticosteroids to prevent neonatal respiratory distress syndrome, and bisphosphonates to treat osteoporosis. Review methods Data were extracted on study design, allocation concealment, number of randomised animals, type of model, intervention, and outcome. Results Corticosteroids did not show any benefit in clinical trials of treatment for head injury but did show a benefit in animal models (pooled odds ratio for adverse functional outcome 0.58, 95% confidence interval 0.41 to 0.83). Antifibrinolytics reduced bleeding in clinical trials but the data were inconclusive in animal models. Thrombolysis improved outcome in patients with ischaemic stroke. In animal models, tissue plasminogen activator reduced infarct volume by 24% (95% confidence interval 20% to 28%) and improved neurobehavioural scores by 23% (17% to 29%). Tirilazad was associated with a worse outcome in patients with ischaemic stroke. In animal models, tirilazad reduced infarct volume by 29% (21% to 37%) and improved neurobehavioural scores by 48% (29% to 67%). Antenatal corticosteroids reduced respiratory distress and mortality in neonates whereas in animal models respiratory distress was reduced but the effect on mortality was inconclusive (odds ratio 4.2, 95% confidence interval 0.85 to 20.9). Bisphosphonates increased bone mineral density in patients with osteoporosis. In animal models the bisphosphonate alendronate increased bone mineral density compared with placebo by 11.0% (95% confidence interval 9.2% to 12.9%) in the combined results for the hip region. The corresponding treatment effect in the lumbar spine was 8.5% (5.8% to 11.2%) and in the combined results for the forearms (baboons only) was 1.7% (−1.4% to 4.7%). Conclusions Discordance between animal and human studies may be due to bias or to the failure of animal models to mimic clinical disease adequately.

Objective To evaluate the effects of dietary and lifestyle interventions in pregnancy on maternal and fetal weight and to quantify the effects of these interventions on obstetric outcomes. Design Systematic review and meta-analysis. Data sources Major databases from inception to January 2012 without language restrictions. Study selection Randomised controlled trials that evaluated any dietary or lifestyle interventions with potential to influence maternal weight during pregnancy and outcomes of pregnancy. Data synthesis Results summarised as relative risks for dichotomous data and mean differences for continuous data. Results We identified 44 relevant randomised controlled trials (7278 women) evaluating three categories of interventions: diet, physical activity, and a mixed approach. Overall, there was 1.42 kg reduction (95% confidence interval 0.95 to 1.89 kg) in gestational weight gain with any intervention compared with control. With all interventions combined, there were no significant differences in birth weight (mean difference −50 g, −100 to 0 g) and the incidence of large for gestational age (relative risk 0.85, 0.66 to 1.09) or small for gestational age (1.00, 0.78 to 1.28) babies between the groups, though by itself physical activity was associated with reduced birth weight (mean difference −60 g, −120 to −10 g). Interventions were associated with a reduced the risk of pre-eclampsia (0.74, 0.60 to 0.92) and shoulder dystocia (0.39, 0.22 to 0.70), with no significant effect on other critically important outcomes. Dietary intervention resulted in the largest reduction in maternal gestational weight gain (3.84 kg, 2.45 to 5.22 kg), with improved pregnancy outcomes compared with other interventions. The overall evidence rating was low to very low for important outcomes such as pre-eclampsia, gestational diabetes, gestational hypertension, and preterm delivery. Conclusions Dietary and lifestyle interventions in pregnancy can reduce maternal gestational weight gain and improve outcomes for both mother and baby. Among the interventions, those based on diet are the most effective and are associated with reductions in maternal gestational weight gain and improved obstetric outcomes.

Background: Alterations in waveforms in the uterine artery are associated with the development of pre-eclampsia and intrauterine growth restriction. We investigated the predictive accuracy of all uterine artery Doppler indices for both conditions in the first and second trimesters. Methods: We identified relevant studies through searches of MEDLINE, EMBASE, the Cochrane Library and Medion databases (all records to April 2006) and by checking bibliographies of identified studies and consulting with experts. Four of us independently selected studies, extracted data and assessed study validity. We performed a bivariable meta-analysis of sensitivity and specificity and calculated likelihood ratios. Results: We identified 74 studies of pre-eclampsia (total 79 547 patients) and 61 studies of intrauterine growth restriction (total 41 131 patients). Uterine artery Doppler ultrasonography provided a more accurate prediction when performed in the second trimester than in the first-trimester. Most Doppler indices had poor predictive characteristics, but this varied with patient risk and outcome severity. An increased pulsatility index with notching was the best predictor of pre-eclampsia (positive likelihood ratio 21.0 among high-risk patients and 7.5 among low-risk patients). It was also the best predictor of overall (positive likelihood ratio 9.1) and severe (positive likelihood ratio 14.6) intrauterine growth restriction among low-risk patients. Interpretation: Abnormal uterine artery waveforms are a better predictor of pre-eclampsia than of intrauterine growth restriction. A pulsatility index, alone or combined with notching, is the most predictive Doppler index. These indices should be used in clinical practice. Future research should also concentrate on combining uterine artery Doppler ultrasonography with other tests.