Zeraatkar Dena, de Souza Russell J, Guyatt Gordon H, Bala Malgorzata M, Alonso-Coello Pablo, Johnston Bradley C
Department of Health Research Methods, Evidence & Impact, McMaster University, Hamilton, Ontario, Canada.
Department of Anesthesia, McMaster University, Hamilton, Ontario, Canada.
BMJ Nutr Prev Health. 2024 Aug 28;7(2):e000835. doi: 10.1136/bmjnph-2023-000835. eCollection 2024.
Due to the challenges of conducting randomised controlled trials (randomised trials) of dietary interventions, evidence in nutrition often comes from non-randomised (observational) studies of nutritional exposures-called nutritional epidemiology studies. When using systematic reviews of such studies to advise patients or populations on optimal dietary habits, users of the evidence (eg, healthcare professionals such as clinicians, health service and policy workers) should first evaluate the rigour (validity) and utility (applicability) of the systematic review. Issues in making this judgement include whether the review addressed a sensible question; included an exhaustive literature search; was scrupulous in the selection of studies and the collection of data; and presented results in a useful manner. For sufficiently rigorous and useful reviews, evidence users must subsequently evaluate the certainty of the findings, which depends on assessments of risk of bias, inconsistency, imprecision, indirectness, effect size, dose-response and the likelihood of publication bias. Given the challenges of nutritional epidemiology, evidence users need to be diligent in assessing whether studies provide evidence of sufficient certainty to allow confident recommendations for patients regarding nutrition and dietary interventions.
由于开展饮食干预随机对照试验（随机试验）存在挑战，营养学方面的证据往往来自对营养暴露的非随机（观察性）研究，即营养流行病学研究。在利用对此类研究的系统评价为患者或人群提供关于最佳饮食习惯的建议时，证据使用者（如临床医生、卫生服务及政策工作者等医疗保健专业人员）应首先评估该系统评价的严谨性（有效性）和实用性（适用性）。做出这一判断时涉及的问题包括：该评价是否解决了一个合理的问题；是否进行了全面的文献检索；在研究选择和数据收集方面是否严谨；以及是否以有用的方式呈现结果。对于足够严谨且有用的评价，证据使用者随后必须评估研究结果的确定性，这取决于对偏倚风险、不一致性、不精确性、间接性、效应大小、剂量反应以及发表偏倚可能性的评估。鉴于营养流行病学的种种挑战，证据使用者需要认真评估研究是否提供了足够确定的证据，以便能够就营养和饮食干预为患者做出有把握的推荐。
