COCHRANE ROB 2 · 偏誤風險評讀
症狀整體緩解(adequate relief)
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總體判斷 OVERALL-High(高風險)
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:Low(低風險)
- -Domain 5 選擇性報告:High(高風險)
- -總體(Overall):High(高風險)
中文摘要(給一般讀者)
這篇論文的偏誤風險與 limitation
本試驗為 13 中心、雙盲、安慰劑對照之 IBS-C 中藥 RCT(n=125)。隨機過程(電腦區組序列、依序編號相同藥瓶、研究人員不知內容)與分配隱匿良好,基線平衡,Domain 1 偏誤風險低。受試者、給藥者、結局評估者(自陳結局即受試者本人)皆盲化,安慰劑外觀完全相符,故偏離介入與結局測量兩域風險低。主要結局 adequate relief 之 ITT 分析涵蓋全部 125 名隨機者並以 LOCF 補值,缺漏資料域風險低。關鍵問題在於選擇性報告:預先指定且適當的 ITT 主要分析其實不顯著(P=.059),但作者在摘要與結論改引納入 108 人的 per-protocol 顯著結果(P=.010)為主要陳述,屬依結果選擇有利分析(5.3 判 PY),且無可比對的事前統計計畫(5.1 判 NI),Domain 5 因而存有疑慮。整體就『指派效果(ITT)』而言,正確採用 ITT 結果(不顯著)時各域大致良好,惟報告層面的選擇性引用 PP 需於 Domain 5 如實反映。
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 was prepared by an administrator with no clinical involvement in the trial by using a computer-generated block four randomization sequence evenly distributed across both arms.隨機分配由一名未參與臨床的行政人員以電腦產生、四為一區組(block four)的隨機序列備妥,於兩組間平均分布。
- 理由:採電腦產生之區組隨機序列,明確含隨機成分,序列產生方式適當。
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:Identical opaque study medication bottles filled by the manufacturer were then numerically labeled according to the randomization sequence... Enrolled participants were assigned their intervention according to the next available sequential bottle number at each site.外觀相同的不透明藥瓶由廠商裝填,依隨機序列編號;納入的受試者依各中心下一個可用的連續藥瓶號碼分配介入。
- 理由:使用外觀一致、依序編號之藥瓶,由廠商裝填、研究人員不知內容,依序不可逆地分配,屬適當的分配隱匿。
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 3 summarizes the similarity in baseline demographics between groups. There were also no significant differences between groups at baseline regarding self-reported symptoms or use of concomitant medication.表 3 顯示兩組基線人口學特徵相近;在自陳症狀或合併用藥方面,兩組基線亦無顯著差異。
- 理由:表 3 各項基線 P 值皆高(如年齡 .704、BMI .131、性別 .786),組別人數 61 對 64 接近 1:1,未見不符隨機的失衡。
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:否(No — 有明確證據支持)
- 原文引述:All participants, investigators, clinicians, researchers/data collectors, referring GPs, and gastroenterologists involved in the trial were blinded to the allocations throughout the study and data entry phase.所有受試者、研究者、臨床醫師、研究人員/資料蒐集者、轉介之家醫科醫師及腸胃科醫師於整個試驗及資料登錄階段皆對分組盲化。
- 理由:雙盲、安慰劑於大小/重量/顏色/味道/氣味與中藥相符,受試者整體未察覺所屬組別(雖第 8 週猜中率有差異,作者判斷係反映療效而非破盲)。
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:否(No — 有明確證據支持)
- 原文引述:All participants, investigators, clinicians, researchers/data collectors, referring GPs, and gastroenterologists involved in the trial were blinded to the allocations throughout the study and data entry phase.所有受試者、研究者、臨床醫師、研究人員/資料蒐集者、轉介之家醫科醫師及腸胃科醫師於整個試驗及資料登錄階段皆對分組盲化。
- 理由:給藥者與照護者亦盲化,安慰劑外觀一致、分配經隱匿,故照護/給藥者不知受試者所屬組別。
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:不需評估(NA)
- 原因:條件題:依 2.1/2.2 的答案,本題依 RoB 2 官方路由不需評估(NA)。
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:Data were analyzed by using SPSS... by using an intention-to-treat (ITT) basis... By using ITT with last value carried forward and including all 125 patients, from commencement to end of intervention 61% of the CHM group (n = 61) and 44% of placebo group (n = 64) changed from no relief to adequate relief (c2, P = .059).資料以 SPSS 採意向治療(ITT)基礎分析……採 ITT、以末次觀測值結轉、納入全部 125 名病人,介入結束時中藥組 61%(n=61)與安慰劑組 44%(n=64)由無緩解轉為達標(卡方 P=.059)。
- 理由:本結局確有提供以全部 125 名隨機者為對象的 ITT 分析(表 4,P=.059),屬估計『指派效果』之適當分析。惟須注意:作者在摘要與結論卻改引不顯著 ITT 之外、納入 108 人的 per-protocol 分析(P=.010)作為主要結論,此選擇性引用問題不影響 2.6(此處仍有 ITT),而於 Domain 5(5.3)反映。
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:ITT analysis was carried out on all 125 participants... Data were analyzed by using... an intention-to-treat (ITT) basis. Any deviations from randomization, missing data, and withdrawals are fully reported, with missing data replaced by using the last value carried forward.ITT 分析以全部 125 名受試者進行……資料以意向治療(ITT)基礎分析;任何偏離隨機、缺漏資料與退出皆完整報告,缺漏資料以末次觀測值結轉補入。
- 理由:主要結局之 ITT 分析涵蓋全部 125 名隨機者(分母 61 與 64),缺漏值以 LOCF 補入後納入分析,等同對此二元結局的所有隨機者皆有可用結果。
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:Low
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:A self-administered validated binary end point measure of global symptom improvement was obtained at each visit, providing a measure of overall adequacy of relief, “Have you had adequate relief of your symptoms over the last two weeks?” (yes/no).於每次訪視以自填之經驗證二元終點測量整體症狀改善,提供整體緩解充分度的指標:「過去兩週您的症狀是否已獲得充分緩解?」(是/否)。
- 理由:「adequate relief」為 IBS-C 試驗公認、經驗證之主要終點,與 FDA/EMA 反應者準則高度一致,測量方法適切。
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:A self-administered validated binary end point measure of global symptom improvement was obtained at each visit於每次訪視以自填之經驗證二元終點測量整體症狀改善。
- 理由:兩組以相同的自填問卷、相同時間點(第 2/4/8/16 週)蒐集結局,測量方法與時點一致,組間不致有差異。
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:否(No — 有明確證據支持)
- 原文引述:All participants, investigators, clinicians, researchers/data collectors, referring GPs, and gastroenterologists involved in the trial were blinded to the allocations throughout the study and data entry phase.所有受試者、研究者、臨床醫師、資料蒐集者、轉介家醫科醫師及腸胃科醫師於整個試驗及資料登錄階段皆對分組盲化。
- 理由:本結局為受試者自陳,結局評估者即受試者本人;受試者已盲化且安慰劑外觀完全相符,故評估者對所受介入盲化。
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:不需評估(NA)
- 原因:條件題:依 4.3 的答案,本題依 RoB 2 官方路由不需評估(NA)。
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:不需評估(NA)
- 原因:條件題:依 4.4 的答案,本題依 RoB 2 官方路由不需評估(NA)。
Domain 5:選擇性報告 — 判斷:High
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:資訊不足(No information — 原文未提供足以判斷的資訊)
- 原文引述:The study aim was to evaluate the efficacy of a standardized CHM preparation for the treatment of IBS-C. Our null hypothesis was the preparation would confer no improvement over placebo... Clinical trial registration no: ACTRN12609000558224.研究目的為評估標準化中藥製劑治療 IBS-C 的療效,虛無假設為該製劑相較安慰劑不會帶來改善;臨床試驗註冊號 ACTRN12609000558224。
- 理由:雖列出試驗註冊號,但報告未提供可資比對、且確定於解盲前定稿的完整統計分析計畫細節,無從確認分析是否完全依事前計畫,故判 NI。
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:A self-administered validated binary end point measure of global symptom improvement was obtained at each visit... (primary outcome).於每次訪視以自填之經驗證二元終點測量整體症狀改善……(主要結局)。
- 理由:adequate relief 為事前指定的單一主要結局測量,且各時間點(第 8 週治療結束、第 16 週追蹤)結果皆有報告,並非自多個量表中擇優呈報,故就『測量』選擇性的疑慮低。
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:可能是(Probably yes — 綜合判斷後傾向「是」)
- 原文引述:There was statistically and clinically significant (per protocol analyses) improvement among subjects who received CHM (n = 50) vs controls (n = 58)... A greater proportion of subjects receiving CHM reported adequate relief (P = .010).依方案(per-protocol)分析,接受中藥者(n=50)相較對照(n=58)有統計與臨床上顯著的改善……中藥組回報達標的比例較高(P=.010)。
- 理由:預先指定且適當的 ITT 主要分析其實不顯著(P=.059),但作者在摘要與結論卻改以納入 108 人的 per-protocol 分析(P=.010)作為主要陳述。此屬就同一結局自多種分析中,依結果(顯著與否)選擇性凸顯有利估計值,提高了報告結果的偏誤風險。