2.摘要
（1）摘要的重要性。摘要的重要性不言而喻。许多读者仅阅读一篇论文的摘要，而不会花大量的时间阅读全文。因此，摘要中要展现论文的精华部分。这个对于其他学者进行论文检索尤为重要。例如，在进行系统综述时，其中一个步骤是对所检索到的论文进行筛查，初筛阶段仅阅读标题和摘要，如果摘要不够全面，那么你的论文就会被漏掉，减少其被引用的概率。更重要的是，稿件提交后第一个阅读（审阅）它的人就是编辑。如果摘要不够清晰、规范，那么稿件很可能在送外审之前就被拒。编辑可能认为：既然摘要都不符合规范，那么正文可能也没有按照投稿指南书写。因此，摘要呈现给编辑的第一印象非常重要。
（2）摘要的基本要求。同标题一样，摘要内容需要简短而丰富。一般情况下，字数在200～300字（具体因期刊而异）。避免在摘要中使用引文，有的期刊甚至要求摘要中不能包含缩写。为了更好地呈现，本书较早地介绍了摘要的书写要求。但一般情况下，摘要会留到全文完成后再写。
（3）摘要的格式。一般情况下，摘要的格式可分为结构式和非结构式。无论是哪种形式，均需要使读者读完以后，知道你的研究做了什么？怎么做？发现了什么？研究发现有何启示？结构式摘要需要给出小标题，包括：背景/目的，方法，结果和结论。根据期刊不同，“背景”可能不需要。有的期刊要求在介绍“方法”前面，有个单独的标题“设计（Design）”（具体格式需要参照相应的期刊进行完善）。对于非结构式摘要，虽然它不要求给出小标题，但是需要包括上述提到的各部分内容。接下来，将对已发表论文的摘要进行剖析，进一步说明每个部分的撰写要点。
1）结构式摘要。
①研究目的（Aim，Purpose或Objective）。“研究目的”这一部分，有些杂志在“投稿指南”里指明，直接给出“To examine...”。此时，作者就开门见山：To examine...。如示例2-1和示例2-2所示。示例2-1中，作者还在摘要中给出了研究假设（hypothesis）。
示例2-1 研究目的举例1
Study objectives：To examine the association between duration trajectories over 28 years and measures of cognition，gray matter volume，and white matter microstructure.We hypothesize that consistently meeting sleep guidelines that recommend at least 7 hours of sleep per night will be associated with better cognition，greater gray matter volumes，higher fractional anisotropy，and lower radial diffusivity values.
示例2-2 研究目的举例2
Aims：To investigate the relationship between depression and self-care behaviors in older individuals with multimorbidity.
还有些作者采用以下格式：The aim of this study was to...。如示例2-3所示。如果字数允许，有些作者还选择在Objective中，给出一定的背景“Background”，如示例2-4所示。
示例2-3 研究目的举例3
Objectives：The aim of this study was to assess if menaquinone supplementation，compared to placebo，decreases vascular calcification in people with type 2 diabetes and known CVD.
示例2-4 研究目的举例4
Study objectives：Major depressive disorder（MDD）is the leading cause of disability worldwide.Its high recurrence rate calls for prevention of first-onset MDD.Although meta-analysis suggested insomnia as the strongest modifiable risk factor，previous studies insufficiently addressed that insomnia might also occur as a residual symptom of unassessed prior depression，or as a comorbid complaint secondary to other depression risks.
此外，还有作者通过说明“研究做了什么”这种形式，给出研究目的，如示例2-5所示：This study evaluated...。
示例2-5 研究目的举例5
Objective：This study evaluated the efficacy of smartphonebased，patient-centered diabetes care system（mDiabetes）for type 2 diabetes that contains comprehensive modules for glucose monitoring，diet，physical activity，and a clinical decision support system.
②研究方法。这一部分，需要体现研究设计、研究对象、干预措施（如果有）、主要研究变量、测量工具（如果字数允许）、主要统计分析方法，如示例2-6和示例2-7所示。有的期刊要求（例如，J Adv Nurs），在“方法”之前，单独给出“Design”，如示例2-6所示）。
示例2-6 研究方法举例1
Design：Cross-sectional study.Data were collected between April 2017 to June 2019.
Methods：Patients were enrolled from community and outpatient settings and included if they were≥65 years，affected by heart failure，diabetes mellitus or chronic obstructive pulmonary disease and at least another chronic condition.They were excluded if they had dementia and/or cancer.Patient Health Questionnaire-9 was used to measure depression and Self-Care of Chronic Illness Inventory was used to measure self-care maintenance，monitoring，and management.The relationship between depression and selfcare was evaluated by performing two sets of univariate analyses，followed by multivariate and step-down analyses.The second set was performed to control for the number of chronic conditions，age，and cognitive function.(https://www.daowen.com)
示例2-7 研究方法举例2
Methods：In total，768 participants from the Netherlands Study of Depression and Anxiety who were free from current and lifetime MDD were followed-up for four repeated assessments，spanning 6years in total.We performed separate Cox proportional hazard analyses to evaluate whether baseline insomnia severity，short-sleep duration，and individual insomnia complaints prospectively predicted first-onset MDD during follow-up.The novel method of network outcome analysis（NOA）allowed us to sort out whether there is any direct predictive value of individual insomnia complaints among several other complaints that are associated with insomnia.
③研究结果。这一部分，需要展示主要研究结果，例如组间差异、相关性分析结果、回归分析结果，如示例2-8和示例2-9所示。【注：根据期刊不同，有的要求提供95%可信区间；有的不允许提供具体统计值和P值】。
示例2-8 研究结果举例1
Results：The sample（N=366）was mostly female（54.2%），with a mean age of 76.4 years.Most participants（65.6%）had mild to very severe depressive symptoms.Preliminary analysis indicated a significant negative association between depression and self-care maintenance and monitoring and a significant negative association between depression and multivariate self-care.Step-down analysis showed that selfcare maintenance was the only dimension negatively associated with depression，even after controlling for the number of chronic conditions，age，and cognitive function.
示例2-9 研究结果举例2
Results：Over 6-year follow-up，141（18.4%）were diagnosed with first-onset MDD.Insomnia severity but not sleep duration predicted first-onset MDD（HR=1.11，95%CI：1.07-1.15），and this was driven solely by the insomnia complaint difficulty initiating sleep（DIS）（HR=1.10，95%Cl：1.04-1.16）.NOA likewise identified DIS only to directly predict first-onset MDD，independent of four other associated depression complaints.
④研究结论。这一部分，根据结果给出相应的结论和（或）建议（针对将来的临床实践及研究），如示例2-10所示。值得注意的是：有些期刊要求撰写完研究结论之后，给出Impact，如示例2-11所示。在撰写Impact时，需要着重说明：本研究所解决的问题，主要研究发现，以及此研究发现会对什么人、什么地方产生影响。
示例2-10 研究结论举例1
Conclusion：In multimorbid populations，depression is more likely to be associated with self-care maintenance than the other self-care dimensions.Therefore，self-care maintenance behaviours（e.g.，physical activity and medication adherence）should be prioritized in assessment and focused on when developing interventions targeting depressed older adults with multimorbidity.
示例2-11 研究结论举例2
Conclusion：The association between nurses'burnout and perceptions of higher rates of adverse events and reduced safety in clinical practice is an important finding.However，it is unclear whether this was influenced by a negative state of mind，and whether reduced safety and increased adverse events negatively influenced nurses'well-being，thus leading to burnout.Regardless，the association between nurses'burnout and these quality concepts needs further exploration to examine the effect，if any，on burnout and safety，and identify supportive mechanisms for nurses.
Impact：The association between reported burnout and perception of safety and risk of adverse events in Italian pediatric nurses has been reported for the first time.Nurses reporting burnout are at greater risk of intensely negative perceptions of clinical safety and adverse events.This is an important finding as perceptions can influence practice and behaviors.Quality measures in children's clinical environments need to go beyond obvious indicators to examine nurses'well-being as this also influences quality and safety.
2）非结构式摘要。
有些期刊要求提交非结构式摘要，如示例2-12和示例2-13所示。虽然此类摘要对书写结构没有特定要求，但它需要包含研究涉及的最基本内容，例如：研究背景、目的、使用到的主要方法、研究结果及结论。
示例2-12 非结构式摘要举例1
Abstract
Previous studies，which included predominantly Caucasian populations，examined psychiatric and physical illness and associated suicide risk.【注：以上是研究背景】We used a nationwide database to reassess the findings in an Asian population，and also analyzed the influence of different onset timing of psychiatric and physical illness and the suicide risk.We included 55，630 suicide cases aged 20-110 years.Using an incidence density sampling approach，we selected 222，520 controls matched by age，sex，and residence area from 2000 to2012.We included most major psychiatric and physical illnesses defined by ICD-9-CM codes with anatomical classifications.【注：以上是研究方法】By using conditional logistic regression models with adjustment of covariates，such as patients'marital status and education levels，we found that patients with psychiatric illness had higher suicide risk（adjusted IRR，7.72；95%CI：7.35-8.09）compared with those with neither physical nor psychiatric illness and the risk increased substantially in patients with both psychiatric and physical illnesses（adjusted IRR，18.35；95%CI：16.40-20.86）.Specifically，we found the suicide risk was relatively higher（adjusted IRR，1.28；95%CI：1.10-1.40）when psychiatric disorders occurred before physical illness compared with the other way around【注：以上是研究结果】The findings warrant attention to high suicide risk and preventive treatments in patients with both psychiatric and physical illnesses.【注：以上是研究结论】
示例2-13 非结构式摘要举例2
Abstract
Novel biomarkers of type 2 diabetes（T2D）and response to preventative treatment in individuals with similar clinical risk may highlight metabolic pathways that are important in disease development.【注：以上是研究背景】We profiled 331 metabolites in 2，015 baseline plasma samples from the Diabetes Prevention Program（DPP）.Cox models were used to determine associations between metabolites and incident T2D，as well as whether associations differed by treatment group（i.e.，lifestyle［ILS］，metformin［MET］，or placebo［PLA］），over an average of 3.2 years of follow-up.【注：以上是研究方法】We found 69 metabolites associated with incident T2D regardless of treatment randomization.In particular，cytosine was novel and associated with the lowest risk.In an exploratory analysis，35 baseline metabolite associations with incident T2D differed across the treatment groups.Stratification by baseline levels of several of these metabolites，including specific phospholipids and AMP，modified the effect that ILS or MET had on diabetes development.【注：以上是研究结果】Our findings highlight novel markers of diabetes risk and preventative treatment effect in individuals who are clinically at high risk and motivate further studies to validate these interactions.【注：以上是研究结论】