馬偕紀念醫院 實證醫學工作小組 2010~2011 方靜如‧劉淑容

Presentation on theme: "馬偕紀念醫院 實證醫學工作小組 2010~2011 方靜如‧劉淑容"— Presentation transcript:

1 馬偕紀念醫院 實證醫學工作小組 2010~2011 方靜如‧劉淑容
馬偕紀念醫院 2010 PGY訓練課程 實證醫學訓練 第一階段 產生問題及文獻搜尋 馬偕紀念醫院 實證醫學工作小組 2010~2011 方靜如‧劉淑容

2 第三節 文獻搜尋

3 文獻搜尋(實際操作，20分鐘) 請根據您剛才寫出的PICO，選擇您最想解決的問題，在馬偕紀念醫院圖書館提供的資源下，找一篇最值得閱讀的文章。

4 第四節 認識文獻的等級及資料庫

5 證據等級 Level Therapy/Prevention, Aetiology/Harm  1a
Systematic review of RCTs + Meta-Analysis  1b Randomized controlled trial (RCT) 1c ‘All-or-none’ 2a Systematic review of cohort studies  2b Cohort study or poor RCT 2c ‘Outcomes’ research ; Ecological studies 3a Systematic review of case-control studies  3b Case-control study  4 Case series 5 Expert opinion without explicit critical appraisal, or based on physiology, bench research or "first principles" Level Therapy/Prevention, Aetiology/Harm 1a Systematic review of RCTs + Meta-Analysis 1b Randomized controlled trial (RCT) 1c ‘All-or-none’ 2a Systematic review of cohort studies 2b Cohort study or poor RCT 2c ‘Outcomes’ research 3a Systematic review of case-control studies 3b Case-control study 4 Case series 5 Expert opinion without explicit critical appraisal, or based on physiology, bench research or "first principles" 證據力強 設計嚴謹 偏差少 並非所有臨床問題都可找到最高等級文獻，但應盡可能使用等級高的證據來源 學員可以只先記紅色字 all-or- none 全有或全無: all patients died before the drug became available, but some now survive on it; or when some patients died before the drug became available, but none now die on it. 無論使用何種研究方法，但其研究結果為完全正面、完全負面或完全無效果 Outcomes research is a broad umbrella term without a consistent definition. However it tends to describe research that is concerned with the effectiveness of public-health interventions and health services; that is, the outcomes of these services. Attention is frequently focused on the affected individual − with measures such as quality of life and preferences − but outcomes research may also refer to effectiveness of health-care delivery, with measures such as cost-effectiveness, health status and disease burden. The present review details the historical background of outcomes research to reveal the origins of its diversity. The value and relevance of outcomes research, commonly employed research techniques and examples of recent publications in the area are also discussed. (Intern Med J 2003; 33: 110−118)   WHAT IS OUTCOMES RESEARCH?"Outcomes research" is a term developed in the past 15 years to describe clinical research concerning the outcomes of medical care (1, 2). Outcomes, broadly defined, can include any variable used to assess the effect of some medical treatment or intervention. "Outcomes research," however, connotes clinical research that focuses less on physiology or biochemical processes and more on clinical end points directly relevant to patients and society: mortality, quality of life, health status, functional status, and costs of care (3, 4). Outcomes research examines the effectiveness of treatment in real clinical settings of heterogeneous patient populations with barriers to treatment rather than the efficacy of treatment in the more controlled research settings with carefully selected, motivated subjects. In addition, outcomes research is concerned with a broad range of issues touching on all aspects of health care delivery, from the clinical encounter between patient and clinician to questions of the organization, financing, and regulation of the health care system. While large, population-based randomized controlled studies using outcomes important to patients (often called "effectiveness trials") are a type of outcomes research, much of outcomes research relies on observational, nonrandomized designs (5). In fact, outcomes research performed by trainees will likely be observational research because of the time and expense involved in performing effectiveness randomized controlled trials. There is a growing recognition of the need for outcomes research, both observational and experimental, to understand and improve the way health care is delivered throughout our society. Although the terms "outcomes research," "clinical epidemiology," and "health services research" have overlapping definitions, we use "outcomes research" in a broad way to include much of the disciplines of clinical epidemiology and health services research. Therefore, we define outcomes research as clinical research attempting to understand and improve the outcomes of illness and medical treatment by focusing on those outcomes important to patients and society. Although it is difficult to draw a sharp line distinguishing outcomes research from other clinical research, many important types of clinical studies are clearly not outcomes studies. For example, small clinical trials using physiologic or biochemical end points are not outcomes research. Nonetheless, faculty performing these other types of clinical research have much to contribute to training outcomes researchers, and trainees interested in other types of clinical research could benefit from many of the tools taught to outcomes researchers. Pulmonary clinicians have been doing outcomes research for at least 25 years. As one example, the Nocturnal Oxygen Therapy Trial in the 1970s used quality of life, as well as survival, as an outcome in a large effectiveness trial to demonstrate the value of oxygen therapy for patients with COPD and hypoxemia (6). The investigators used this study to describe the effect of COPD on the quality of life in these patients (7). Since that time, there has been a large body of work assessing the quality of life and functional status of patients with COPD and asthma and using these measures to determine the effectiveness of treatments (8). Critical care researchers have been among the leaders in assessing outcomes of medical care and performing risk adjustment to control for severity of illness. The APACHE score was one of the earliest validated systems to assess risk, control for severity of illness, and predict outcome (14), and the APACHE III remains one of the most comprehensive and accurate risk adjustment systems available (15). Assessing outcomes and predictors of outcomes in critical care has been an important and vital area of research for three decades. 5: 未經考證之專家個人意見, 基礎研究, 細胞實驗, 生理實驗, 動物實驗…的結果 證據力弱 設計薄弱 偏差多 表濃縮自: Oxford Centre for EBM Levels of Evidence(第1版) 第2版亦於 上線:

6 Randomized Controlled Trial (RCT) 隨機對照試驗
有病 沒病 鏈黴素 第一個隨機對照試驗在大英帝國完成，有趣的是推動這項鏈黴素研究的原因不是科學方法的進展，而是因為當時醫療人員只有全部結核病人所需要的一半鏈黴素。鏈黴素是在第二次世界大戰期間開發試驗的，戰後鏈黴素的試驗，由傷口照護轉移到結核病。大不列顛醫學研究理事會覺得最公平的分配方法就是機率，於是…第一次有了經隨機分派的治療組與控制組。(Medical Research Council. Streptomycin treatment of pulmonary tuberculosis. BMJ 1948;2:769–782.) Ann McKibbon著；楊宗翰譯。實證醫學原理與應用快速入門，p.24-25。台北市：合記，2008。 A randomized controlled study is one in which: 1. There are two groups, one treatment group and one control group. The treatment group receives the treatment under investigation, and the control group receives either no treatment or some standard default treatment. 2. Patients are randomly assigned to all groups. Assigning patients at random reduces the risk of bias and increases the probability that differences between the groups can be attributed to the treatment. Having a control group allows us to compare the treatment with alternative choices. For instance, the statement that a particular medication cures 40% of cases tells us very little unless we also know how many cases get better on their own! (Or with a different treatment). With certain research questions, randomized controlled studies cannot be done for ethical reasons. For instance, it would be unethical to attempt to measure the effect of smoking on health by asking one group to smoke two packs a day and another group to abstain, since the smoking group would be subject to unnecessary harm. Randomized controlled trials are the standard method of answering questions about the effectiveness of different therapies. If you have a therapy question, first look for a randomized controlled trial, and only go on to look for other types of studies if you don't find one. 有病 沒病 安慰劑 結核病人 有介入‧有對照‧有隨機 SUNY Downstate EBM Tutorial: ,

7 觀察性研究方法。大多是前瞻性，也有少數是回溯性。
Cohort Study 世代研究 肺癌 無肺癌 檢驗有(或無)暴露在某種介入的子群組之間差異 抽菸者 一群界定清楚的人 世代研究，是一種觀察性研究方法(observational study)，一群界定清楚的人 (the cohort) 被追蹤一段時間。檢驗結果( outcome) 在不同次群組之間是否有差異，例如有（或沒有）暴露在某種介入之次群組，觀察其結果發生率。世代研究大多是前瞻性的，但也有少數是回溯性的（必須相關記錄非常清楚）。(資料來源:彰基醫圖電子報第3期) A Cohort Study is a study in which patients who presently have a certain condition and/or receive a particular treatment are followed over time and compared with another group who are not affected by the condition under investigation. For instance, since a randomized controlled study to test the effect of smoking on health would be unethical, a reasonable alternative would be a study that identifies two groups, a group of people who smoke and a group of people who do not, and follows them forward through time to see what health problems they develop. Cohort studies are not as reliable as randomized controlled studies, since the two groups may differ in ways other than in the variable under study. For example, if the subjects who smoke tend to have less money than the non-smokers, and thus have less access to health care, that would exaggerate the difference between the two groups. The main problem with cohort studies, however, is that they can end up taking a very long time, since the researchers have to wait for the conditions of interest to develop. Physicians are, of course, anxious to have meaningful results as soon as possible, but another disadvantage with long studies is that things tend to change over the course of the study. People die, move away, or develop other conditions, new and promising treatments arise, and so on. Even so, cohort studies are generally preferred to case control studies , since they involve far fewer statistical problems and generally produce more reliable answers. 肺癌 無肺癌 非抽菸者 觀察性研究方法。大多是前瞻性，也有少數是回溯性。 SUNY Downstate EBM Tutorial: ,

8 Case Control Study 病例對照研究
癌症病人 抽菸者 非抽菸者 Case control studies are studies in which patients who already have a certain condition are compared with people who do not. For example: a study on which lung cancer patients are asked how much they smoked in the past and the answers are compared with a sample of the general population would be a case control study. Case control studies are less reliable than either randomized controlled trials or cohort studies. Just because there is a statistical relationship between two conditions does not mean that one condition actually caused the other. For instance, lung cancer rates are higher for people without a college education (who tend to smoke more), but that does not mean that someone can reduce his or her cancer risk just by getting a college education. The main advantages of case control studies are: • They can be done quickly. By asking patients about their past history, researchers can quickly discover effects that otherwise would take many years to show themselves. • Researchers don't need special methods, control groups, etc. They just take the people who show up at their institution with a particular condition and ask them a few questions. The first study to suggest a new medical conclusion will often be a case control study, perhaps designed to check on a hypothesis suggested by a case series. If possible, researchers will generally try to confirm the results with a randomized controlled trial or a cohort study. 非癌症病人 抽菸者 非抽菸者 SUNY Downstate EBM Tutorial: ,

9 Case Series and Case Report 病例系列與病例報告
Case series and case reports consist either of collections of reports on the treatment of individual patients, or of reports on a single patient. For example: one of your patients has a condition that you have never seen or heard of before and you are uncertain what to do. A search for case series or case reports may reveal information that will assist in a diagnosis. However, for any reasonably well-known condition you should be able to get better evidence. Case series and case reports, since they use no control group with which to compare outcomes, have no statistical validity . SUNY Downstate EBM Tutorial: ,

10 Systematic Review + Meta-Analysis 系統性評論 + 統合分析
(通常是RCT) 提出一個特定的臨床問題 執行完整文獻搜尋 排除不適用的研究 評析設計良好且適用的研究 歸結臨床應用上的可行建議 Systematic Review Important medical questions are typically studied more than once, often by different research teams in different locations. A systematic review is a comprehensive survey of a topic in which all of the primary studies of the highest level of evidence have been systematically identified, appraised and then summarized according to an explicit and reproducible methodology. A meta-analysis is a survey in which the results of all of the included studies are similar enough statistically that the results are combined and analyzed as if they were one study. In general a good systematic review or meta-analysis will be a better guide to practice than an individual article. Pitfalls specific to meta-analysis include: 1. It's rare that the results of the different studies precisely agree, and often the number of patients in a single study is not large enough to come up with a decisive conclusion. 2. If the authors are interested in supporting a particular conclusion, they can include studies that support that conclusion and omit studies that do not. Do the authors explain in their paper exactly on what basis they included studies , and do their reasons make sense? 3. Studies that show some kind of positive effect tend to be published more often than those that do not. This means that if the authors include only published studies, several weak positive studies may seem to add up to a strong positive result. Do weak negative studies exist? This effect is known as Publication bias. 基於systematic review 將個別研究數據進行統計學量化分析 歸結出一個證據力更強的結論 Unsystematic narrative “review”: 混合個人意見和證據，而證據搜集也常岀自reviewer個人的選擇 SUNY Downstate EBM Tutorial: ,

11 搜尋實證障礙 不知道怎麼定義關鍵字 資源太多，不知道從何下手 不熟悉搜尋方式
PICO, plus 同義字, MeSH Terms 資源太多，不知道從何下手 FIRST: Filtered Resources (EBM Databases) PLUS: Unfiltered Resources (Medline) 不熟悉搜尋方式 只找到/看到片面現象(B)，而非貼近事實(A) (Information bias) 只搜尋特定資料庫如Medline是不夠的，還有EMBASE、PsyINFO、CINAHL、未出版的灰色文獻 只找到/看到局部事實: 原文是應用Systematic Review過程中的出版品偏差，此處延伸應用到搜尋 (Information bias) Montori VM, Smieja M, Guyatt GH (2000). Publication bias. Mayo Clin Proc 75: Publication bias. A, The black circle represents the underlying truth. The white square represents the pooled estimate from a systematic review of all the evidence (small shaded circles). B, The white circles represent evidence that was not identified by the reviewers because it was not published. Note the error in the pooled estimate (publication bias).

12 資料庫的選擇與使用 資源金字塔 http://library.mmh.org.tw/EBMR.htm
無法遠端 Free Free 資源金字塔

13 5S EBM Resources (非關證據強弱!)
愈上層 資訊精萃 簡單的關鍵字 省時搜尋與評讀 快速支援決策 由下層積累 1.systems 連結個別病歷的臨床知識與支援決策系統 整合證據提供特定臨床問題之概述與建議 UpToDate BMJ Clinical Evidence FirstConsult ACP PIER 2.summaries Filtered Resources 對單篇研究或回顧性文獻作摘要與評述 ACP Journal Club, Evidence-Based Medicine (PubMed, Ovid Medline) 3.synopses 特定臨床問題的系統性評論文獻 Cochrane Database of Systematic Reviews Database of Abstracts of Reviews of Effects (PubMed, Ovid Medline): Systematic Reviews 4.syntheses 愈下層 文獻雜多 完整的關鍵字 費時搜尋與評讀 注重檢索技巧 資訊新穎 原始文獻 (PubMed, Ovid Medline, CINAHL, EMBASE Cochrane CENTRAL, Google Scholar CEPS中文電子期刊, 中文期刊篇目索引) Unfiltered Resources 5.studies Model from: Haynes, R. B. (2006). Of studies, syntheses, synopses, summaries, and systems: the "5S" evolution of information services for evidence-based health care decisions. ACP Journal Club, 145(3), A8.

14 PICO檢索示範 P I C O  一位胃食道逆流的患者 使用proton pump inhibitor 與不使用藥物治療
Patient/Problem 一位胃食道逆流的患者 I Intervention 使用proton pump inhibitor C Comparison 與不使用藥物治療 O Outcomes 是否能改善聲音沙啞 Type □Diagnosis □Therapy □Prognosis □Harm □Etiology 

15 PICO檢索示範 – 關鍵字 (初級班) P I C O  gastroesophageal reflux PPI
Patient/Problem gastroesophageal reflux I Intervention PPI C Comparison non-drug therapies OR placebos OR… O Outcomes hoarseness Type □Diagnosis □Therapy □Prognosis □Harm □Etiology 

16 UpToDate: Search gastroesophageal reflux PPI hoarseness 輸入疾病、症狀、藥物、程序
輸入單字(hoarseness)、縮寫(PPI)、片語(gastroesophageal reflux )、字頭(gastro)、詞或句子 不要輸入布林邏輯: AND、OR gastroesophageal reflux PPI hoarseness gastroesophageal reflux PPI hoarseness

17 UpToDate: Result 大綱 內文 部份會提供推薦與證據等級 如果病人有中度到嚴重的，我們推薦使用PPI勝於H2RA
Grade 1 : 表示強烈推薦，大部分病人接受此治療，好處大於傷害 Grade A: 表示引用的文獻證據品質良好，例如執行良好的RCT或觀察性研究 部份會提供推薦與證據等級

18 Clinical Evidence: Search (英式拼法)
GERD  到符合關鍵字的段落  到Topic主頁

19 Clinical Evidence: Result
表列各種介入的益害: 有益．可能有益．未知療效．益害參半．可能有害．有害

20 Clinical Evidence: Result

21 Clinical Evidence: GRADE Table
基於OR/RR/HR顯示的效果大小 0: 所有/大多研究顯示一致結果 0: 族群與結果具廣泛類推性 4: RCT / SR of RCT 0: 品質沒問題(blind, follow up…) Type of evidence: 4 = RCT; 2 = Observational Consistency: similarity of results across studies Directness: generalisability of population or outcomes Effect size: based on relative risk or odds ratio

22 資訊檢索概念 單字 vs. 片語 (PubMed使用會關閉自動比對MeSH功能, 適合在非MeSH Term使用)
intensive care vs. “intensive care” 病人服藥遵從性行為 vs. “病人服藥遵從性行為 ” 切截字 (PubMed使用會關閉自動比對MeSH功能, 適合在非MeSH Term使用) therap* : therapy , therapeutic , therapeutics convention*: convention, conventional 同義字 廣狹義詞 布林邏輯 檢索欄位 自由詞彙 vs. 控制詞彙

23 單字 vs. “片語” (Google範例) "服藥" "遵從" "行為"

24 廣狹義字 同義字 資訊檢索概念 單複數 英美拼法 廣義字 全名縮寫 狹義字 同義異形字 (用MeSH可避免大部分困擾) inhibitor
inhibitors esophageal reflux gastro-oesophageal reflux GERD gastroesophageal reflux lymph node removal lymphadenectomy lymph nodes excision lymph nodes dissection 住院病人 住院病患 雙腿截肢 下肢截肢 膝下截肢 單複數 英美拼法 廣義字 資訊檢索概念 全名縮寫 狹義字 同義異形字 (用MeSH可避免大部分困擾)

25 布林邏輯: AND 地瓜 營養 地 瓜 營 養 AND

26 布林邏輯: OR 地瓜 蕃藷 地 瓜 蕃 薯 OR

27 布林邏輯: NOT 地瓜 地 瓜 種 植 NOT

28 營養 AND 地瓜 OR 蕃薯 地瓜 OR 蕃薯 AND 營養 (地瓜 OR 蕃薯) AND 營養 布林邏輯: 運算規則 營 養 地 瓜
大部分是由左至右進行運算 營 養 地 瓜 蕃 薯

29 布林邏輯: 運算規則 由左至右進行運算 加括弧先運算 4 x 2 + 4 x 3 營 養 地 瓜 蕃 薯
營養 AND 地瓜 OR 蕃薯 ( X ) 地瓜 OR 蕃薯AND 營養 ( O ) 加括弧先運算 營養 AND (地瓜 OR 蕃薯) ( O ) 4 x ( ) = 營養 AND 地瓜 OR 營養 AND 蕃薯 4 x x 3 營 養 地 瓜 蕃 薯 大部分的系統是先乘除後加減進行運算，但是有的系統是由左至右進行運算

30 檢索欄位 篇名 Title 作者關鍵字 Keyword 摘要 Abstract 控制詞彙 MeSH Term 全文 Full Text
所有欄位 All Fields 影響檢索結果的相關性 !

31 檢索欄位: 哪一篇文章相關性高? (糖尿病)  

32 檢索欄位: 哪一篇文章相關性低? (roselle洛神花 )
  

33 articles translation database translation queries 自由詞彙 vs. 控制詞彙
authors articles translation 系統控制使用者和作者用語一致 使用者要設法和作者心意相通 Gastroesophageal Reflux 控制詞彙派 Controlled Vocabulary 自由詞彙派 Free Text database Medline Standard Medical Subject Headings 較大型或精緻的書目資料庫 通常同時有這兩種機制 自由詞彙派 Free text (例: summaries型資料庫、Google) 原理 User所輸入關鍵字會直接比對原始篇名、摘要、作者 (、內文)等欄位若吻合，文章就會被找出 優 user檢索過程較簡單 適用控制詞彙未提供的概念。如新名詞；或形容用語，如initial treatment 缺 語義容易模糊 要儘可能列舉同義詞 可能要列舉狹義詞 ======================================================= 控制詞彙派 Controlled vocabulary (例: MeSH: Medical Subject Headings) 索引專家預先給每篇文章分類主題(控制詞彙) User所輸入關鍵字會被嘗試轉譯成控制詞彙 若1與2吻合，文章就會被找出 解決同義字問題 可彈性檢索廣/狹義詞 使用得宜可提高精確率與回收率 user要”習慣”’才會用 新概念不適用 用語容易受限不彈性 Gastroesophageal Reflux translation 自由詞彙 vs. 控制詞彙 GERD user queries

34 自由詞彙 vs. 控制詞彙 (Free Text) (Controlled Vocabulary)
例: 中文期刊論文資料庫、Google 檢索時系統比對原始文章的篇名、摘要作者等欄位 搜尋過程上較簡單 適用控制詞彙未提供的概念 新名詞: Severe Acute Respiratory Syndrome於2003始為MeSH 形容語: repeated fine-needle aspiration => repeat* 要儘可能列舉同義詞 => (intensive OR tight OR strict) AND glycemic control 語義容易模糊 => Roselle vs Roselle 可能要列舉狹義詞 例: Medline: MeSH、CINAHL Headings 檢索時系統將關鍵字比對控制詞彙表後做查詢 (文獻事前經索引程序) 解決同義字問題 可彈性檢索廣/狹義詞 可調整精確率與回收率 要”習慣”’才會用 新概念不適用 用語容易受限不彈性 原 理 優 點 缺 點

35 PubMed: General Search (預設介面)
進階查詢介面 輸入關鍵字、布林邏輯、檢索編號 此PubMed網址和馬偕圖書館電子館藏有建立連結，可以把此網址加入我的最愛 醫學主題標題表 臨床最佳化篩選

36 PubMed: Advance Search (進階介面)
系統轉譯關鍵字細節 輸入關鍵字、布林邏輯、檢索編號 指定欄位檢索 檢索歷史(保留8hr) 看此筆檢索結果 點#數字彈跳選項

37 PubMed: Details 控制詞彙 自由詞彙 系統的最終的檢索策略 [MeSH Terms]: 醫學主題標題詞
[TIAB]: Title篇名與Abstract摘要 [Text Word]: 所有文字欄位，含Title、Abstract 、MeSH terms、Publication Types、Substance Names、Personal Name [All Fileds]: 所有欄位 系統的轉譯過程 控制詞彙 自由詞彙 使用者輸入關鍵字

38 PubMed: Search (初級班) gastroesophageal reflux AND PPI AND hoarseness

39 PubMed / Ovid Medicine: 檢索技巧
 使用 MeSH Term與列舉同義字  彈性組合 P I C O  透過線索修正關鍵字  最佳化篩選 Clinical Queries  指定期刊 ACP J Club Cochrane Reviews…  限制條件 Limits  限定欄位 [major] OR [title] (調整相關性密技)

40 PubMed: 使用MeSH 與列舉同義字
Patient/Problem gastroesophageal reflux OR GERD OR esophageal reflux OR gastro-esophageal reflux OR gastro-oesophageal reflux I Intervention PPI OR PPIs OR proton pump inhibitor OR proton pumps C Comparison non-drug therapies OR placebos OR… O Outcomes hoarseness Type □Diagnosis □Therapy □Prognosis □Harm □Etiology gastroesophageal reflux OR GERD OR esophageal reflux OR gastro-esophageal reflux OR gastro-oesophageal reflux PPI OR PPIs OR proton pump inhibitor OR proton pumps hoarseness  紅線底線字表示為MeSH Term，底線字表示可轉譯為MeSH Term 關鍵字加了切截字元* 或 ”雙引號” 即停用自動比對MeSH功能

41 PubMed: 使用MeSH 1. 避免使用縮寫 2. 檢查Details 3. 參考已知書目的MeSH Terms
4. 查詢MeSH Database確認用語 2. 檢查Details

42 Demo: P PubMed: 彈性組合 P I C O 輸入P關鍵字
gastroesophageal reflux OR GERD OR GORD OR esophageal reflux OR gastro-esophageal reflux OR gastro-oesophageal reflux 輸入P關鍵字 gastroesophageal reflux OR GERD OR GORD OR esophageal reflux OR gastro-esophageal reflux OR gastro-oesophageal reflux

43 Demo 輸入I 關鍵字 PPI OR PPIs OR proton pump inhibitor OR proton pumps

44 Demo hoarseness 輸入O 關鍵字 hoarseness

45 Demo #2 AND #3 AND #4 開始組合檢索

46 PubMed: 彈性組合 P I C O 避免某個面向檢索結果很低，影響整體檢索結果 檢索結果低時，易修正檢索策略 方便後續彈性組合檢索
I O P I P I O O I P 避免某個面向檢索結果很低，影響整體檢索結果 檢索結果低時，易修正檢索策略 方便後續彈性組合檢索 PICO何重要? 取決臨床問題特性、檢索者目的和時間、文獻需求質量

47 PubMed: 透過線索修正關鍵詞 文章乙: 篇名與摘要: 都未提到hoarseness
只有atypical manifestations 找到一篇文章甲：摘要中提到 hoarseness是GERD的atypical symptom 文章乙: 內文: 有提及hoarseness (關鍵詞不一定會表現在篇名與摘要) Search #2 AND #3 AND (#4 OR atypical) =165篇 Search #2 AND #3 AND #4 = 72篇

48 PubMed: 透過線索修正關鍵詞 研究設計 年齡層 研究設計 性別 主題 主題 參考關鍵書目的MeSH
來修正關鍵詞，如"proton pumps" 年齡層 研究設計 性別 主題 主題

49 PubMed: 指定期刊ACP, Cochrane
輸入關鍵字或#號碼 即自動將檢索策略帶入此區塊 按鈕Search/Preview #6 AND (“ACP journal club”[Journal] OR "Cochrane database of systematic reviews (Online)"[Journal]) 按鈕Add to… 輸入刊名關鍵字 ACP journal club acp... 指定欄位 #3 ("ACP journal club"[Journal] OR "Cochrane database of systematic reviews (Online)"[Journal]) 選取AND 繼續以OR加入其他期刊直到完成

50 EBM評論文章 原始研究

51 ACP J Club: 濃縮10頁原始研究為1頁EBM評論
結果 結論 原始研究 臨床問題 評論 研究方法 參考書目

52 PubMed: 最佳化篩選Clinical Queries
#8 或#6 臨床面向  99 文獻量  6 為何使用#8(198筆)來篩選Systematic Reviews，而非#5(24筆) (1) 文獻量太少，再做篩選更少 (2) 關鍵字未必表現在一篇文章的篇名、摘要，也未必有被分派到MeSH Term，故不易被檢出；一篇SR所評讀的文獻範圍很廣、分析項目很多 (3) 試看看使用#5來篩選，將會找不到一些重要文章 Filter citations for systematic reviews, meta-analyses, reviews of clinical trials, evidence-based medicine, consensus development conferences, and guidelines. See related sources. Filter citations to a specific clinical study category and scope. These search filters were developed by Haynes RB et al.

53 Clinical Queries using Research Methodology Filters
Category Optimized For Sensitive Specific PubMed Equivalent therapy sensitive/ broad 99% 70% ((clinical[Title/Abstract] AND trial[Title/Abstract]) OR clinical trials[MeSH Terms] OR clinical trial[Publication Type] OR random*[Title/Abstract] OR random allocation[MeSH Terms] OR therapeutic use[MeSH Subheading]) specific/ narrow 93% 97% (randomized controlled trial[Publication Type] OR (randomized[Title/Abstract] AND controlled[Title/Abstract] AND trial[Title/Abstract])) diagnosis sensitive/ broad 98% 74% (sensitiv*[Title/Abstract] OR sensitivity and specificity[MeSH Terms] OR diagnos*[Title/Abstract] OR diagnosis[MeSH:noexp] OR diagnostic * [MeSH:noexp] OR diagnosis,differential[MeSH:noexp] OR diagnosis[Subheading:noexp]) specific/ narrow  64% (specificity[Title/Abstract]) etiology 93% 63% (risk*[Title/Abstract] OR risk*[MeSH:noexp] OR risk *[MeSH:noexp] OR cohort studies[MeSH Terms] OR group*[Text Word])  51% 95% ((relative[Title/Abstract] AND risk*[Title/Abstract]) OR (relative risk[Text Word]) OR risks[Text Word] OR cohort studies[MeSH:noexp] OR (cohort[Title/Abstract] AND stud*[Title/Abstract])) prognosis 90% 80% (incidence[MeSH:noexp] OR mortality[MeSH Terms] OR follow up studies[MeSH:noexp] OR prognos*[Text Word] OR predict*[Text Word] OR course*[Text Word]) 52% 94% (prognos*[Title/Abstract] OR (first[Title/Abstract] AND episode[Title/Abstract]) OR cohort[Title/Abstract]) clinical prediction guides 96% 79% (predict*[tiab] OR predictive value of tests[mh] OR scor*[tiab] OR observ*[tiab] OR observer variation[mh]) 54% 99% (validation[tiab] OR validate[tiab])

54 PubMed:  Limits       #8
謹慎: 使用Limits後， In process 、supplied by publisher、非Medline 的文獻，將被排除～ 因為此機制是針對已被Medline做過索引程序的書目所設計 #8       勿與Type of Article併用

55 PubMed: 限定欄位[major] OR [title]
GERD[majr] OR GERD[ti] OR gastroesophageal reflux[ti] (調整相關性密技) GERD[majr] OR GERD[ti] OR gastroesophageal reflux[ti] GERD[mesh] OR GERD[ti] OR gastroesophageal reflux[ti] GERD 高 低

56 PubMed: Search Strategy (中級班)
 Limits  Clinical Queries  指定期刊  修正關鍵字 I O P I gastroesophageal reflux AND PPI AND hoarseness gastroesophageal reflux OR GERD OR esophageal reflux OR gastro-esophageal reflux OR gastro-oesophageal reflux PPI OR PPIs OR proton pump inhibitor OR proton pumps hoarseness #2 AND #3 AND #4 #2 AND #3 #3 AND #4 #2 AND #3 AND (#4 OR atypical) #6 AND ("acp journal club"[Journal] OR "cochrane database of systematic reviews online"[Journal])  使用MeSH / 同義字  彈性組合 P I O O I P 初級PICO(快速法)

57 PubMed: Filter your results
    

58 再次文獻搜尋(實際操作，30分鐘) 請重新搜尋電腦，找尋具有最佳證據的 一篇文獻，來回答您的問題。
請根據今天上課的內容，完成實證醫學學習單並繳回。

59 請記得完成並繳回 你(妳)的實證醫學學習單，謝謝! 實証醫學工作小組 敬上
謝謝您的參與! 請記得完成並繳回 你(妳)的實證醫學學習單，謝謝! 實証醫學工作小組 敬上