Peer-assisted learning in medical education: A systematic review and meta-analysis.

OBJECTIVES: The prevalence of peer-assisted learning (PAL) featuring alongside the core medical curriculum is increasing; however, the evidence base for PAL's efficacy on academic performance is limited. This systematic review of randomised studies of PAL in medical school sets out to assess the impact of PAL on academic outcomes in medical school and evaluate whether PAL confers a benefit in specific educational contexts. METHODS: A literature search was conducted across MEDLINE, Ovid Embase, Web of Science and Education Research Complete. Titles and abstracts were screened, and records were selected following strict eligibility criteria. Following full-text assessment for eligibility, two reviewers independently extracted data from the final selection of records and a meta-analysis was performed. Studies were classified using a modified version of Kirkpatrick's levels of learning. Student test scores were standardised by calculating the standardised mean difference (SMD). RESULTS: Twenty-seven randomised controlled trials were eligible for inclusion, and twenty-one provided sufficient and complete data to enable meta-analysis. There was a significant improvement in the academic performance of medical students who received PAL compared with those in the control group (SMD = 0.52 [95% confidence interval 0.18-0.85]; p = .003). The impact of PAL was greater amongst clinical medical students (SMD = 0.63; p = .02) than preclinical medical students (SMD = 0.39; p = .08) and when used for teaching practical skills (SMD = 0.69; p = .001) compared with theory (SMD = -0.11; p = .21). Students taught by PAL also achieved better results in assessments conducted more than four weeks after course completion (SMD = 1.20; p = .04). [Correction added on 8 November 2020 after first publication. The data values in the Results section have been corrected in this version.] CONCLUSIONS: Medical students experiencing PAL benefit in terms of academic performance, relative to those not receiving PAL. PAL is of greatest value in the clinical stages of training and for practical skills. The long-term outcomes of PAL remain a priority for future research.

Exploring the use and quality of Internet discussion forums in pregnancy: A qualitative analysis.

BACKGROUND: The Internet is widely used as a source of health information to assist decision making in pregnancy. Concerningly, the quality of information shared on online pregnancy forums is unclear. Our objectives were to explore online pregnancy forum health-related use and evaluate quality of information shared. METHODS: This retrospective qualitative study had two phases of data collection and analysis. First, thematic analysis of a representative sample (n = 480) of posts explored motivators for forum use. Second, a subgroup (n = 153) of threads with clinical content was assessed for congruence with reputable sources. RESULTS: Common motivators for forum engagement were a desire for lived experience, unlimited access, and the opportunity to express emotions. Of 1098 responses sharing advice, information, or experience, 601 (54.7%) were accurate; 230 (20.9%) were erroneous, incomplete, or misleading; and 267 (24.3%) lacked credible evidence. Of these, 60 (5.5%) were potentially harmful. Responses often directed women to a health care practitioner, but concerningly, failed to refer ten women in need of urgent medical assessment. Few discussions were self-regulating, with only 12 of 230 (5.2%) poor-quality messages subsequently rectified. CONCLUSIONS: Exchange of information and emotional support among peers are key functions of online pregnancy forums. There is a modest prevalence of poor-quality or potentially harmful information but more concerningly a lack of peer moderation. We suggest health care practitioners ensure pregnant women have a clear understanding of when clinical consultation is required. Clinicians may wish to discuss the supportive community aspects of online forums in cases where offline support is lacking.

Mediterranean-style diet for the primary and secondary prevention of cardiovascular disease.

BACKGROUND: The Seven Countries study in the 1960s showed that populations in the Mediterranean region experienced lower coronary heart disease (CHD) mortality probably as a result of different dietary patterns. Later observational studies have confirmed the benefits of adherence to a Mediterranean dietary pattern on cardiovascular disease (CVD) risk factors but clinical trial evidence is more limited. OBJECTIVES: To determine the effectiveness of a Mediterranean-style diet for the primary and secondary prevention of CVD. SEARCH METHODS: We searched the following electronic databases: the Cochrane Central Register of Controlled Trials (CENTRAL; 2018, Issue 9); MEDLINE (Ovid, 1946 to 25 September 2018); Embase (Ovid, 1980 to 2018 week 39); Web of Science Core Collection (Thomson Reuters, 1900 to 26 September 2018); DARE Issue 2 of 4, 2015 (Cochrane Library); HTA Issue 4 of 4, 2016 (Cochrane Library); NHS EED Issue 2 of 4, 2015 (Cochrane Library). We searched trial registers and applied no language restrictions. SELECTION CRITERIA: We selected randomised controlled trials (RCTs) in healthy adults and adults at high risk of CVD (primary prevention) and those with established CVD (secondary prevention). Both of the following key components were required to reach our definition of a Mediterranean-style diet: high monounsaturated/saturated fat ratio (use of olive oil as main cooking ingredient and/or consumption of other traditional foods high in monounsaturated fats such as tree nuts) and a high intake of plant-based foods, including fruits, vegetables and legumes. Additional components included: low to moderate red wine consumption; high consumption of whole grains and cereals; low consumption of meat and meat products and increased consumption of fish; moderate consumption of milk and dairy products. The intervention could be dietary advice, provision of relevant foods, or both. The comparison group received either no intervention, minimal intervention, usual care or another dietary intervention. Outcomes included clinical events and CVD risk factors. We included only studies with follow-up periods of three months or more defined as the intervention period plus post intervention follow-up. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed studies for inclusion, extracted data and assessed risk of bias. We conducted four main comparisons:1. Mediterranean dietary intervention versus no intervention or minimal intervention for primary prevention;2. Mediterranean dietary intervention versus another dietary intervention for primary prevention;3. Mediterranean dietary intervention versus usual care for secondary prevention;4. Mediterranean dietary intervention versus another dietary intervention for secondary prevention. MAIN RESULTS: In this substantive review update, 30 RCTs (49 papers) (12,461 participants randomised) and seven ongoing trials met our inclusion criteria. The majority of trials contributed to primary prevention: comparisons 1 (nine trials) and 2 (13 trials). Secondary prevention trials were included for comparison 3 (two trials) and comparison 4 (four trials plus an additional two trials that were excluded from the main analyses due to published concerns regarding the reliability of the data).Two trials reported on adverse events where these were absent or minor (low- to moderate-quality evidence). No trials reported on costs or health-related quality of life.Primary preventionThe included studies for comparison 1 did not report on clinical endpoints (CVD mortality, total mortality or non-fatal endpoints such as myocardial infarction or stroke). The PREDIMED trial (included in comparison 2) was retracted and re-analysed following concerns regarding randomisation at two of 11 sites. Low-quality evidence shows little or no effect of the PREDIMED (7747 randomised) intervention (advice to follow a Mediterranean diet plus supplemental extra-virgin olive oil or tree nuts) compared to a low-fat diet on CVD mortality (hazard ratio (HR) 0.81, 95% confidence interval (CI) 0.50 to 1.32) or total mortality (HR 1.0, 95% CI 0.81 to 1.24) over 4.8 years. There was, however, a reduction in the number of strokes with the PREDIMED intervention (HR 0.60, 95% CI 0.45 to 0.80), a decrease from 24/1000 to 14/1000 (95% CI 11 to 19), moderate-quality evidence). For CVD risk factors for comparison 1 there was low-quality evidence for a possible small reduction in total cholesterol (-0.16 mmol/L, 95% CI -0.32 to 0.00) and moderate-quality evidence for a reduction in systolic (-2.99 mmHg (95% CI -3.45 to -2.53) and diastolic blood pressure (-2.0 mmHg, 95% CI -2.29 to -1.71), with low or very low-quality evidence of little or no effect on LDL or HDL cholesterol or triglycerides. For comparison 2 there was moderate-quality evidence of a possible small reduction in LDL cholesterol (-0.15 mmol/L, 95% CI -0.27 to -0.02) and triglycerides (-0.09 mmol/L, 95% CI -0.16 to -0.01) with moderate or low-quality evidence of little or no effect on total or HDL cholesterol or blood pressure.Secondary preventionFor secondary prevention, the Lyon Diet Heart Study (comparison 3) examined the effect of advice to follow a Mediterranean diet and supplemental canola margarine compared to usual care in 605 CHD patients over 46 months and there was low-quality evidence of a reduction in adjusted estimates for CVD mortality (HR 0.35, 95% CI 0.15 to 0.82) and total mortality (HR 0.44, 95% CI 0.21 to 0.92) with the intervention. Only one small trial (101 participants) provided unadjusted estimates for composite clinical endpoints for comparison 4 (very low-quality evidence of uncertain effect). For comparison 3 there was low-quality evidence of little or no effect of a Mediterranean-style diet on lipid levels and very low-quality evidence for blood pressure. Similarly, for comparison 4 where only two trials contributed to the analyses there was low or very low-quality evidence of little or no effect of the intervention on lipid levels or blood pressure. AUTHORS' CONCLUSIONS: Despite the relatively large number of studies included in this review, there is still some uncertainty regarding the effects of a Mediterranean-style diet on clinical endpoints and CVD risk factors for both primary and secondary prevention. The quality of evidence for the modest benefits on CVD risk factors in primary prevention is low or moderate, with a small number of studies reporting minimal harms. There is a paucity of evidence for secondary prevention. The ongoing studies may provide more certainty in the future.

Mediterranean-Style Diet for the Primary and Secondary Prevention of Cardiovascular Disease: A Cochrane Review.

Background: Diet plays a major role in cardiovascular disease (CVD) risk. Objectives: To determine the effectiveness of a Mediterranean-style diet for the primary and secondary prevention of CVD. Methods: We searched for randomised controlled trials (RCTs) of Mediterranean-style diets in healthy adults and those at increased risk of CVD (primary prevention) and with established CVD (secondary prevention). Results: Thirty RCTs were included, 22 in primary prevention and eight in secondary prevention. Clinical endpoints were reported in two trials where there was moderate quality evidence for a reduction in strokes for primary prevention, and low quality evidence for a reduction in total and CVD mortality in secondary prevention. We found moderate quality evidence of improvement in CVD risk factors for primary prevention and low quality evidence of little or no effect in secondary prevention. Conclusions: There is still some uncertainty regarding the effects of a Mediterranean-style diet in CVD prevention.