COCHRANE ROB 2 · 偏誤風險評讀
VADAS-cog 認知變化
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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:Some concerns(有些疑慮)
- +Domain 4 結局測量:Low(低風險)
- ?Domain 5 選擇性報告:Some concerns(有些疑慮)
- ?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
本研究為 16 中心、三臂(天智顆粒、donepezil、安慰劑,4:4:1)雙盲雙模擬隨機對照試驗,評讀天智顆粒對安慰劑在第 24 週 VADAS-cog 變化量的比較。隨機序列由 SAS 電腦產生,並以依序編號、外觀相同的藥盒隱匿分配,基線相近,隨機化過程偏誤風險低。受試者、照顧者、研究者皆盲,未見偏離介入,主要分析採修正型 ITT(排除隨機後未服藥者),介入偏離面向風險低。結局由盲化研究者以標準量表評估,測量面向風險低。主要疑慮在缺失資料:約兩成受試者第 24 週無實測值、以 LOCF 補值,中止者多為原因不明的失去追蹤,雖然各組缺失比例相近,仍無法排除缺失與結局有關。選擇性報告方面,試驗為招募期間回溯註冊、未見事前統計分析計畫,但主要結局與分析方法在方法段明確界定且兩種族群結果一致。整體而言,偏誤主要來自缺失資料處理與回溯註冊。
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:Using SAS 9.3, a biostatistics expert developed a computing procedure statement with set seeds, and a random number table was generated.生物統計專家以 SAS 9.3 撰寫設定種子的程式,產生亂數表。
- 理由:由生物統計專家以 SAS 9.3 電腦產生亂數表,並採區組隨機、4:4:1 分配,屬於適當的隨機序列產生方法。
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:each subject was provided with the appropriate kit, with a drug number matching the case number ... When a qualified subject was enrolled into the trial, the kit with the appropriate case number, in the order of subject enrollment, was provided.每位受試者依病例編號領取藥物編號相符的藥盒……合格受試者入組時,依入組順序發給對應病例編號的藥盒。
- 理由:採藥廠預先編碼、依入組順序發放的藥盒,三組藥物(含安慰劑與重新包裝的 donepezil)外觀口味相同,盲底分兩層密封保存於研究單位與藥廠。依序編號、外觀相同的藥盒屬於官方指引認可的隱匿方式,招募者無法預知下一位的組別。
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:Demographic characteristics of patients in all groups were similar at baseline (Table 1).各組病人的基線人口學特徵相近(表 1)。
- 理由:表 1 顯示天智組與安慰劑組在年齡、性別、教育、VADAS-cog(52.64 vs 52.22)、MMSE、NPI 等基線值都很接近,安慰劑組 TMT-A/B 稍高但屬 55 人小組的機率波動,未見暗示隨機化出問題的系統性差異。
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:Patients, caregivers, the study investigator, any other personnel involved in the study, and the investigating staffs of the Henan Wanxi pharmaceutical Co were blinded until all patients complete the study and all data were collected.病人、照顧者、研究者、其他參與研究的人員及宛西製藥的調查人員,在所有病人完成試驗、資料收集完畢前皆不知分組。
- 理由:採雙模擬(double-dummy)設計,安慰劑與真藥外觀口味相同,受試者不知道自己被分到哪一組。
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:否(No — 有明確證據支持)
- 原文引述:To preserve blinding, the placebo had an identical taste and appearance to the experimental drugs.為維持盲性,安慰劑的口味與外觀與試驗藥物相同。
- 理由:照顧者與研究者皆被盲化(見 2.1 引文),且藥物外觀口味一致,施治與照護者不知分組。
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:可能是(Probably yes — 綜合判斷後傾向「是」)
- 原文引述:The full analysis set (FAS), which based on the intent-to-treat population (ITT), consisting of all randomized population who toke at least one dose of medication and at least one primary efficacy evaluation on treatment.全分析集(FAS)以意向治療族群為基礎,包含所有至少服用一劑藥物且在治療中至少有一次主要療效評估的隨機分配受試者。
- 理由:主要分析採 FAS(修正型 ITT),依隨機分配組別分析。排除的是隨機後未服藥且失聯者(天智 10/242、安慰劑 5/60),官方指引認為雙盲試驗中排除未開始介入者可接受;排除造成的結局缺失交由 Domain 3 處理。
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:Some concerns
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:否(No — 有明確證據支持)
- 原文引述:Of these 520 patients, 75 subjects discontinued their treatments ... For missing data at endpoint, a last observation carried forward (LOCF) analysis was used.這 520 人中有 75 人中止治療……終點缺失資料以末次觀察值推估(LOCF)處理。
- 理由:隨機 543 人中,第 24 週實際完成天智組 195/242(81%)、安慰劑組 46/60(77%),另有 23 人隨機後即失聯未進入分析。約兩成受試者的主要結局是以 LOCF 補值,並非幾乎所有人都有結局資料。
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:可能否(Probably no — 綜合判斷後傾向「否」)
- 原文引述:The same results were obtained in the PPS population.符合計畫書族群(PPS)得到相同結果。
- 理由:LOCF 補值與完成者(PPS)分析都假設缺失與真值無關,官方指引認為這類敏感度分析不足以證明結果未受缺失資料偏誤,故判 PN。
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:可能是(Probably yes — 綜合判斷後傾向「是」)
- 原文引述:Of these 520 patients, 75 subjects discontinued their treatments, and reasons for discontinued medication were shown in Fig. 1.這 520 人中有 75 人中止治療,中止原因見圖 1。
- 理由:圖 1 流程圖顯示中止者絕大多數記為「失去追蹤」(天智組 37 人中 35 人、安慰劑組 9 人中 6 人),未說明原因;失智症病人失聯可能與認知退步或療效不佳有關,缺失有可能取決於結局真值。
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:可能否(Probably no — 綜合判斷後傾向「否」)
- 原文引述:there was no significant difference between three treatment groups in completion rates (placebo, 76.67%; donepezil, 83.82%; TZ, 80.58%).三組完成率無顯著差異(安慰劑 76.67%、donepezil 83.82%、天智 80.58%)。
- 理由:雙盲下各組缺失比例相近(天智約 19%、安慰劑約 23%),缺失原因也類似(多為失去追蹤、因不良事件退出極少),沒有證據顯示缺失很可能與結局真值有關,故判 PN。
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:The changes of the Vascular Dementia Assessment Scale-Cognitive Subscale (VADAS-cog/17items) from baseline after 24 weeks treatment were adopted as the primary endpoint以治療 24 週後血管性失智評估量表認知分量表(VADAS-cog,17 項)自基線的變化量作為主要終點。
- 理由:VADAS-cog 是針對血管性失智修訂的標準化認知量表,適合測量本結局。
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:Efficacy measurements were taken at baseline, and at weeks 4, 12 and 24.療效評估於基線、第 4、12 與 24 週進行。
- 理由:三組使用同一量表、同一時間點評估,測量方式在組間沒有差異。
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:Patients, caregivers, the study investigator, any other personnel involved in the study, and the investigating staffs of the Henan Wanxi pharmaceutical Co were blinded until all patients complete the study and all data were collected.病人、照顧者、研究者及其他參與人員在資料收集完畢前皆不知分組。
- 理由:VADAS-cog 由研究人員施測,研究者與所有參與人員皆被盲化,結局評估者不知分組。
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:Some concerns
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 protocol was failed to register before participant recruitment.試驗計畫書未能在受試者招募前完成註冊。
- 理由:試驗於 2015 年 5 月在 ClinicalTrials.gov 回溯註冊(招募期為 2013 年 10 月至 2017 年 5 月),雖然仍在解盲前,但論文未提供事前定案的統計分析計畫,也無法從文中確認註冊內容與分析一致,資訊不足。
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 changes of the Vascular Dementia Assessment Scale-Cognitive Subscale (VADAS-cog/17items) from baseline after 24 weeks treatment were adopted as the primary endpoint以治療 24 週後 VADAS-cog 自基線的變化量作為主要終點。
- 理由:主要結局量表(VADAS-cog 17 項)與時間點(第 24 週)在方法段明確界定,並依此報告,沒有跡象顯示是從多個量表或時間點中挑選。
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:ANCOVA models that included baseline score, treatment, and centre as covariates were used to assess differences between the treatment groups for linear efficacy measures.以納入基線分數、治療與中心為共變項的 ANCOVA 模型評估各組在連續療效指標上的差異。
- 理由:方法段預先說明 ANCOVA 模型與 ITT-LOCF/PPS 兩種族群,且兩種族群結果都報告、方向一致,沒有跡象顯示從多種分析中挑選有利者。