COCHRANE ROB 2 · 偏誤風險評讀
每週排便次數改變(第4週)
← 回到「腸躁症」的圖表
總體判斷 OVERALL?Some concerns(有些疑慮)
Domain 與 overall 判斷由程式依 Cochrane RoB 2 官方演算法計算;AI 只負責回答下方各訊號問題。符號:+ 低風險、? 有些疑慮、- 高風險(不只靠顏色)。
風險偏誤紅綠燈
- +Domain 1 隨機化過程:Low(低風險)
- +Domain 2 偏離預定介入:Low(低風險)
- +Domain 3 缺失結局資料:Low(低風險)
- ?Domain 4 結局測量:Some concerns(有些疑慮)
- +Domain 5 選擇性報告:Low(低風險)
- ?總體(Overall):Some concerns(有些疑慮)
中文摘要(給一般讀者)
這篇論文的偏誤風險與 limitation
本篇為 8 中心、4 臂(He 電針/Shu-Mu 電針/He-Shu-Mu 電針/loperamide)平行組等效 RCT,主要結局為第 4 週每週排便次數自基線改變量、電針 vs loperamide 的組間比較(結果等效)。隨機化面向佳:電腦產生可變區組序列、依腹瀉類型與病程分層、中央伺服器封存序列做到分配隱匿,基線大致均衡。ITT 面向穩健:主分析採 ITT 族群+多重插補、並有 PP 敏感度分析一致,域2 用適當分析估計指派效果。缺失資料少(第 4 週僅約 11 人失訪、約 96% 有資料),且插補與 PP 結果一致,域3 風險低。選擇性報告面向:試驗事前註冊、主要結局與分析事前明訂並完整呈報 ITT/PP/MI,僅未明文交代統計計畫解盲前定案,屬低度疑慮。主要偏誤集中在結局測量:電針屬 open-label、受試者/施針者/醫師皆未設盲,而主要結局為未設盲病人自填腹瀉日記(病人=評估者知情,4.3=Y),有受知情影響之虞;惟排便次數為可計數的相對客觀事件、不若整體主觀量表易受扭曲,判尚未達「很可能」被影響(4.5=PN),故整體偏誤傾向落在『部分疑慮』,主要來源為未盲之病人自報結局。
詳細評讀(給專業讀者)
Domain 1:隨機化過程 — 判斷:Low
偏誤來源:隨機分組的過程——分配序列是否隨機產生、是否隱蔽到分組為止、基線(第一期開始時)是否平衡。
1.1 Was the allocation sequence random?
分配序列是否隨機產生?
- 回答:是(Yes — 有明確證據支持)
- 原文引述:Randomization sequence was generated by a computer system in the CEC-CACMS. Permuted block randomization with changing block size was used, and the randomization was stratified according to the type of diarrhea (IBS-D or FD) and duration of diarrhea.隨機序列由 CEC-CACMS 的電腦系統產生,採用可變區組大小的排列區組隨機化,並依腹瀉類型(IBS-D 或 FD)與腹瀉病程分層。
- 理由:電腦產生序列、可變區組排列區組法並做分層隨機,屬明確的隨機方法,序列為隨機。
1.2 Was the allocation sequence concealed until participants were enrolled and assigned to interventions?
分配是否隱蔽到分組為止?
- 回答:是(Yes — 有明確證據支持)
- 原文引述:The study coordinator in each hospital obtained a randomization code and group assignment through an internet-based randomization system or a message delivering system... The randomization sequence was concealed in the secure server in the CEC-CACMS until all the follow-up visits and data collection were finished and study files were locked.各醫院的研究協調員透過網路隨機化系統或手機簡訊派送系統取得隨機碼與分組;隨機序列鎖在 CEC-CACMS 安全伺服器中,直到所有追蹤訪視與資料蒐集完成、研究檔案鎖定為止。
- 理由:採中央化網路/簡訊即時派碼、序列封存於安全伺服器直到收案分配後,分配隱匿到納入前,隱匿充分。
1.3 Did baseline differences between intervention groups suggest a problem with the randomization process?
(第一期開始時)基線差異是否暗示隨機化有問題?
- 回答:否(No — 有明確證據支持)
- 原文引述:Table 1 shows these variables separately in the 4 groups. The age of all participants was 40.5 years, and 253 (57.3%) of them were females... The participants presented a stool frequency of 16.0 times/week and a Bristol score of 6.1 at baseline.表1呈現四組各項基線變數,整體年齡 40.5 歲、女性 57.3%,基線排便頻率約每週 16 次、Bristol 分數 6.1。
- 理由:表1四組人口學與症狀基線大致相當(loperamide 組排便頻率 14.6 略低於其他組 16 上下,屬小幅差異),無暗示隨機化出問題的異常不均。
Domain 2:偏離預定介入 — 判斷:Low
偏誤來源:實際執行時偏離預定的介入——盲性如何、是否依「隨機分到的組別」分析(ITT)。
2.1 Were participants aware of their assigned intervention during the trial?
參與者是否(在每一期)知道自己的分組?
- 回答:是(Yes — 有明確證據支持)
- 原文引述:As participants receive loperamide alone in the control group, the participants, acupuncturists, and doctors in charge were not blinded from the group assignment.由於對照組僅服用 loperamide,受試者、施針者與主治醫師皆未對分組設盲。
- 理由:四臂中電針屬 open-label、對照為口服西藥,受試者明確知道自己分到哪一組。
2.2 Were carers and people delivering the interventions aware of participants' assigned intervention during the trial?
照護/執行者是否(在每一期)知道分組?
- 回答:是(Yes — 有明確證據支持)
- 原文引述:the participants, acupuncturists, and doctors in charge were not blinded from the group assignment. The statisticians were masked from the group assignments.受試者、施針者與主治醫師皆未設盲;統計人員則對分組設盲。
- 理由:施治者(施針者)與主治醫師皆知道分組,照顧者/施治者未設盲。
2.3 Were there deviations from the intended intervention that arose because of the trial context?
是否因試驗情境造成偏離?
- 回答:可能否(Probably no — 綜合判斷後傾向「否」)
- 原文引述:In the 3 electroacupuncture groups, concomitant treatments (moxibustion, cupping, herbs and conventional medications other than loperamide) were not allowed. Patients with acute diarrhea symptoms during the treatment or follow-up period were asked to visit gastroenterologists to determine if rescue medications were needed.三個電針組禁止合併治療(艾灸、拔罐、中藥及 loperamide 以外的常規藥物);治療或追蹤期間出現急性腹瀉症狀者請其看消化科醫師評估是否需救援藥物。
- 理由:介入本身差異屬試驗設計預期,非「因試驗情境而生的偏離」;未報告有兩組不對等、超出常規照護的介入偏離,兩組均有一致的救援藥物路徑,故判無此類偏離。
2.4 Were these deviations likely to have affected the outcome?
這些偏離是否可能影響結局?
- 回答:不需評估(NA)
- 原因:條件題:依 2.3 的答案,本題依 RoB 2 官方路由不需評估(NA)。
2.5 Were these deviations from intended intervention balanced between groups?
這些偏離在兩組間是否平衡?
- 回答:不需評估(NA)
- 原因:條件題:依 2.4 的答案,本題依 RoB 2 官方路由不需評估(NA)。
2.6 Was an appropriate analysis used to estimate the effect of assignment to intervention?
是否用了適當分析(ITT)?
- 回答:是(Yes — 有明確證據支持)
- 原文引述:All analyses were performed on the basis of intention-to-treat (ITT) population... We handled missing values through multiple imputation (MI) performed with the package "Amelia" in the R software.所有分析以意向治療(ITT)族群為基礎進行,缺失值以 R 軟體 Amelia 套件的多重插補(MI)處理。
- 理由:主分析採 ITT 族群並以多重插補處理缺失(另有 PP 敏感度分析一致),屬估計「指派效果」的適當分析。
2.7 Was there potential for a substantial impact (on the result) of the failure to analyse participants in the group to which they were randomized?
未依隨機分組分析,是否可能對結果造成重大影響?
- 回答:不需評估(NA)
- 原因:條件題:依 2.6 的答案,本題依 RoB 2 官方路由不需評估(NA)。
Domain 3:缺失結局資料 — 判斷:Low
偏誤來源:結局資料缺失——是否幾乎所有人都有資料、缺失是否可能與病情(結局真實值)相關。
3.1 Were data for this outcome available for all, or nearly all, participants randomized?
是否幾乎所有受試者都有此結局的資料?
- 回答:是(Yes — 有明確證據支持)
- 原文引述:Five participants did not report primary outcome at baseline, 11 participants were lost to follow-up at week 4, and 19 participants at week 8. A total of 441 participants were included in the ITT population... We handled missing values through multiple imputation (MI).5 人基線未報告主要結局、11 人於第 4 週失訪、19 人於第 8 週失訪;ITT 族群共納入 441 人,缺失值以多重插補處理。
- 理由:主要結局在第 4 週,觀察到資料約 430/448(約 96%)、僅約 11 人失訪並以多重插補補足,幾乎所有受試者都有結局資料。
3.2 Is there evidence that the result was not biased by missing outcome data?
是否有證據顯示結果未受缺失資料偏誤?
- 回答:不需評估(NA)
- 原因:條件題:依 3.1 的答案,本題依 RoB 2 官方路由不需評估(NA)。
3.3 Could missingness in the outcome depend on its true value?
缺失是否可能取決於結局真實值?
- 回答:不需評估(NA)
- 原因:條件題:依 3.2 的答案,本題依 RoB 2 官方路由不需評估(NA)。
3.4 Is it likely that missingness in the outcome depended on its true value?
缺失是否很可能取決於結局真實值?
- 回答:不需評估(NA)
- 原因:條件題:依 3.3 的答案,本題依 RoB 2 官方路由不需評估(NA)。
Domain 4:結局測量 — 判斷:Some concerns
偏誤來源:結局的測量——測量工具是否恰當、評估者是否盲化、評估是否可能受分組知情影響。
4.1 Was the method of measuring the outcome inappropriate?
結局測量方法是否不適當?
- 回答:否(No — 有明確證據支持)
- 原文引述:The primary outcome was the change from baseline in stool frequency at the end of the 4-weeks treatment... All these outcomes were assessed and recorded weekly in the diarrhea diaries.主要結局為 4 週療程結束時每週排便次數自基線的改變量,由每週腹瀉日記記錄。
- 理由:以排便次數(可計數事件)作為腹瀉的療效指標,經日記逐週記錄,測量方法對此結局屬適當,非不當。
4.2 Could measurement or ascertainment of the outcome have differed between intervention groups?
(每一序列內)結局測量是否可能因介入而異?
- 回答:否(No — 有明確證據支持)
- 原文引述:Research assistants guided the participants on how to fill in the diarrhea diaries, to ensure the fidelity of the outcome data. The outcome assessors extracted the information from the diaries into calculable variables.研究助理指導受試者如何填寫腹瀉日記以確保資料真實性;結局評估者再從日記擷取為可計算變數。
- 理由:兩組皆採同一套腹瀉日記與相同擷取流程量測結局,測量方式在組間一致,不會因組別而不同。
4.3 Were outcome assessors aware of the intervention received by study participants?
結局評估者是否知道受試者接受的介入?
- 回答:是(Yes — 有明確證據支持)
- 原文引述:the participants... were not blinded from the group assignment... All these outcomes were assessed and recorded weekly in the diarrhea diaries.受試者未對分組設盲;各結局由受試者每週記錄於腹瀉日記中。
- 理由:主要結局為病人自填日記(病人=實質評估者),而病人在 open-label 下知道自己的分組,故結局評估者知情。雖有不知分組的研究助理擷取資料,但原始評估來自未設盲的病人。
4.4 Could assessment of the outcome have been influenced by knowledge of intervention received?
結局評估是否可能受介入知情影響?
- 回答:可能是(Probably yes — 綜合判斷後傾向「是」)
- 原文引述:it might be a placebo effect, which plays an important role in functional bowel disorders. The response rate of functional bowel disorders to placebo varied from 3% to 84%.(療效)可能含安慰劑效應,安慰劑在功能性腸道疾病扮演重要角色,其反應率介於 3% 到 84%。
- 理由:主要結局屬未設盲病人自我報告,作者自陳功能性腸道疾病安慰劑效應強,病人對分組的預期可能影響其排便次數的記錄與報告,故有受知情影響之虞。
4.5 Is it likely that assessment of the outcome was influenced by knowledge of intervention received?
結局評估是否很可能受介入知情影響?
- 回答:可能否(Probably no — 綜合判斷後傾向「否」)
- 原文引述:The primary outcome was the change from baseline in stool frequency at the end of the 4-weeks treatment.主要結局為 4 週療程結束時每週排便次數自基線的改變量。
- 理由:排便次數為可客觀計數的事件,相較於整體症狀主觀量表較不易受判斷影響;雖為病人自填有受影響之虞(4.4),但尚不足以認定「很可能」被知情實質扭曲,故判否(域4落在部分疑慮而非高風險)。
Domain 5:選擇性報告 — 判斷:Low
偏誤來源:選擇性報告結果——是否依事前訂定的分析計畫分析、有無從多個結果中挑選有利者報告(交叉另含:是否因偵測到殘留而只報第一期)。
5.1 Were the data that produced this result analysed in accordance with a pre-specified analysis plan that was finalized before unblinded outcome data were available for analysis?
是否依事前訂定(取得未盲化資料前定版)的分析計畫分析?
- 回答:可能是(Probably yes — 綜合判斷後傾向「是」)
- 原文引述:The trial was registered at clinicaltrials.gov (registration ID: NCT01350570)... The primary outcome was the change from baseline in stool frequency at the end of the 4-weeks treatment. The primary analysis was to reject H0 through an analysis of covariance (ANCOVA) of the primary outcome.試驗於 clinicaltrials.gov 註冊(NCT01350570);主要結局為第 4 週每週排便次數自基線改變量,主分析以 ANCOVA 檢定主要結局。
- 理由:試驗事前註冊、主要結局與 ANCOVA 主分析於方法中明訂,報告的主要結局與分析與事前計畫相符;惟未明文說明統計計畫於解盲前定案,故判可能是而非確定。
5.2 Is the numerical result being assessed likely to have been selected, on the basis of the results, from multiple eligible outcome measurements (e.g. scales, definitions, time points) within the outcome domain?
此數值結果是否可能依結果,從多個量表/定義/時間點中選出?
- 回答:可能否(Probably no — 綜合判斷後傾向「否」)
- 原文引述:The primary outcome was the change from baseline in stool frequency at the end of the 4-weeks treatment.主要結局明訂為第 4 週每週排便次數自基線的改變量。
- 理由:主要結局為單一事前指定的量測(第 4 週排便次數改變),無證據顯示係從多個量測中挑選有利者呈報。
5.3 Is the numerical result being assessed likely to have been selected, on the basis of the results, from multiple eligible analyses of the data?
此數值結果是否可能依結果,從多種分析中選出?
- 回答:可能否(Probably no — 綜合判斷後傾向「否」)
- 原文引述:We used the PP and MI dataset to rerun the analysis, the results were consistent with the ITT analysis. Table 2 shows more details.以 PP 與 MI 資料集重跑分析,結果與 ITT 分析一致,詳見表2。
- 理由:主分析採事前指定的 ITT ANCOVA,並完整呈報 ITT/PP/MI 多種分析且結果一致,無證據顯示從多個分析中挑選有利結果呈報。