COCHRANE ROB 2 · 偏誤風險評讀
臨床皮損總分改善(8 週)
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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:Some concerns(有些疑慮)
- ?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
本試驗為台灣單中心、平行兩組、2:1 隨機、雙盲安慰劑對照試驗,以消風散濃縮顆粒治療難治型異位性皮膚炎 8 週。隨機序列由獨立統計師以電腦產生並封存,藥包外觀一致,隨機化過程的偏誤風險低。患者與評估醫師皆採盲性,安慰劑仿照外觀與味道,偏離介入的風險低;分析排除 2 位未服藥者,但人數極少。缺失資料方面,第 8 週主要結局約 11% 受試者無資料,消風散組缺失較多,且未做敏感度分析,存在一些疑慮。結局測量由盲性醫師以標準化皮損評分完成,風險低。選擇性報告方面,沒有試驗註冊或事前分析計畫可對照,屬一些疑慮。整體而言,本結局的偏誤主要來自缺失資料與缺乏事前計畫,但組間差異極大(改善 79.10 vs 13.50 分),偏誤不太可能改變結論方向。
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:The computer-generated randomization list was drawn up by an independent statistician and placed in an envelope until the study was completed.隨機分配表由獨立統計師以電腦產生,並封存於信封中直到研究結束。
- 理由:以電腦產生隨機序列(2:1),屬適當的隨機方法。
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:可能是(Probably yes — 綜合判斷後傾向「是」)
- 原文引述:The computer-generated randomization list was drawn up by an independent statistician ... Eligible patients were assigned consecutive randomized numbers as they entered the study. ... Placebo was made of caramel, lactose and starch at a ratio of 2:1:1 and put into identical-appearing 3-gram packs.隨機表由獨立統計師產生……合格患者入組時依序取得連續的隨機編號。……安慰劑由焦糖、乳糖與澱粉以 2:1:1 製成,裝入外觀完全相同的 3 克藥包。
- 理由:隨機表由獨立統計師保管、封存至研究結束,患者依入組順序取得連續編號,而藥包外觀完全相同(由藥廠統一包裝),相當於依序編號、外觀一致的藥物容器,收案者難以預知下一位的分組。論文未明寫藥包編號與發放流程細節,故答「可能是」。
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:可能否(Probably no — 綜合判斷後傾向「否」)
- 原文引述:There was no significant difference between the 2 treatment groups with regard to baseline characteristics.兩組的基線特徵沒有顯著差異。
- 理由:年齡、性別、病程、皮損總分、紅斑、表面損傷、搔癢等基線皆無顯著差異;只有睡眠分數呈邊緣差異(p=0.050),屬隨機誤差可以解釋的程度,不足以暗示隨機過程有問題。
Domain 2:偏離預定介入 — 判斷:Some concerns
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:可能否(Probably no — 綜合判斷後傾向「否」)
- 原文引述:Patients and the evaluating physicians were unaware during the study of whether the medication taken by the patients was placebo or the treatment drug. ... The placebo mixture has no known benefit in atopic dermatitis but has a similar appearance and taste to the active treatment.研究期間,患者與評估醫師都不知道患者服用的是安慰劑還是試驗藥物。……安慰劑對異位性皮膚炎無已知療效,但外觀與味道和試驗藥相似。
- 理由:採雙盲,安慰劑外觀與味道仿照消風散。摘要提到部分患者抱怨藥難喝,理論上可能讓人猜到組別,但安慰劑也刻意做成相似味道,整體判斷受試者可能不知分組。
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:可能否(Probably no — 綜合判斷後傾向「否」)
- 原文引述:Patients and the evaluating physicians were unaware during the study of whether the medication taken by the patients was placebo or the treatment drug.研究期間,患者與評估醫師都不知道患者服用的是安慰劑還是試驗藥物。
- 理由:評估與看診醫師不知分組,藥包由藥廠統一包裝、外觀一致,照顧者(多為兒童患者的家屬)也只拿到相同藥包,判斷可能不知分組。
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:可能否(Probably no — 綜合判斷後傾向「否」)
- 原文引述:Two patients (1 in the XFS group, 1 in the control group) who were not treated with any investigational drugs were dropped from the study at baseline (week 0), so that a total of 69 patients (46 in the XFS group, 23 in the placebo group) were included in the intention-to-treat population.兩位患者(消風散組、對照組各 1 位)在基線(第 0 週)未接受任何試驗藥物即退出研究,因此共 69 位患者(消風散組 46 位、安慰劑組 23 位)納入意向治療族群。
- 理由:論文稱的「意向治療族群」排除了隨機後未服任何試驗藥的 2 位(每組各 1 位),依官方指引,排除未接受介入的隨機受試者屬不適當分析;另有缺失值的受試者未納入分析(此部分屬 Domain 3,不在此扣分)。故答「可能否」。
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:否(No — 有明確證據支持)
- 原文引述:Two patients (1 in the XFS group, 1 in the control group) who were not treated with any investigational drugs were dropped from the study at baseline (week 0), so that a total of 69 patients (46 in the XFS group, 23 in the placebo group) were included in the intention-to-treat population.兩位患者(消風散組、對照組各 1 位)在基線(第 0 週)未接受任何試驗藥物即退出研究,因此共 69 位患者(消風散組 46 位、安慰劑組 23 位)納入意向治療族群。
- 理由:被不當排除的只有 71 人中的 2 人(2.8%),且兩組各 1 人,面對組間約 66 分的巨大差異(79.10 vs 13.50),不可能對結果造成實質影響。
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:There were 5 missing values in the XFS group and 1 missing value in the placebo group. ... Fifty-nine of the patients (83%) completed the treatment period消風散組有 5 筆缺失值,安慰劑組有 1 筆缺失值。……共 59 位患者(83%)完成治療期。
- 理由:第 8 週主要結局分析:消風散組 47 人隨機中約 41 人有資料(87%),安慰劑組 24 人中約 22 人有資料(92%),整體約 63/71(89%),未達連續型結局常用的 95% 門檻。
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:否(No — 有明確證據支持)
- 原文引述:原文未提供相關描述
- 理由:論文只用有資料者做共變數分析,沒有做敏感度分析或多重插補,無法證明結果不受缺失資料偏誤影響。
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:10 patients (9 in the XFS group and 1 in the placebo group) were excluded from the per-protocol population due to poor compliance (5 in the XFS group and 1 in the placebo group), refusal to continue treatment (in the XFS group, 2 were too busy, 1 was afraid to have blood drawn) and use of a prohibited drug (1 in the XFS group).10 位患者(消風散組 9 位、安慰劑組 1 位)因服藥順從性差(消風散組 5 位、安慰劑組 1 位)、拒絕繼續治療(消風散組 2 位太忙、1 位害怕抽血)及使用禁用藥物(消風散組 1 位)而被排除於依計畫分析族群之外。
- 理由:缺失原因包括順從性差、使用禁用藥物等,可能與病情(例如皮膚炎發作而自行用藥、覺得無效而不服藥)有關;摘要也提到部分患者覺得藥難喝,順從性差可能與療效感受相關,因此缺失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:10 patients (9 in the XFS group and 1 in the placebo group) were excluded from the per-protocol population due to poor compliance (5 in the XFS group and 1 in the placebo group), refusal to continue treatment (in the XFS group, 2 were too busy, 1 was afraid to have blood drawn) and use of a prohibited drug (1 in the XFS group).10 位患者(消風散組 9 位、安慰劑組 1 位)因服藥順從性差(消風散組 5 位、安慰劑組 1 位)、拒絕繼續治療(消風散組 2 位太忙、1 位害怕抽血)及使用禁用藥物(消風散組 1 位)而被排除於依計畫分析族群之外。
- 理由:多數缺失有記錄原因且與病情無明顯關聯(太忙、怕抽血、家人不同意);兩組缺失比例差距不大(約 13% vs 8%)。加上組間差異極大(79.10 vs 13.50),缺失資料很可能不足以扭轉結論,判斷「很可能取決於真值」的證據不足。
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 extent and severity of the dermatitis was assessed by quantitative measurement of erythema and surface damage (i.e. papulation, vesiculation, scaling, excoriation and lichenification) using a standardized scoring system以標準化評分系統,量化測量紅斑與表面損傷(即丘疹、水泡、脫屑、抓痕與苔癬化),評估皮膚炎的範圍與嚴重度。
- 理由:採已發表的標準化全身 20 區評分系統,適合測量異位性皮膚炎的皮損嚴重度。
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:They took the herbal treatment or placebo daily for 8 weeks and were assessed at the beginning of the study and after 4, 8 and 12 weeks.受試者每日服用中藥或安慰劑 8 週,並於研究開始時及第 4、8、12 週接受評估。
- 理由:兩組使用相同量表、相同評估時間點,測量方式沒有組間差異。
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:可能否(Probably no — 綜合判斷後傾向「否」)
- 原文引述:Patients and the evaluating physicians were unaware during the study of whether the medication taken by the patients was placebo or the treatment drug.研究期間,患者與評估醫師都不知道患者服用的是安慰劑還是試驗藥物。
- 理由:主要結局由評估醫師評分,醫師在研究期間不知分組;雖有部分患者覺得藥難喝,但評估者本人是醫師,判斷評估者可能不知分組。
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:For the primary outcome, the clinical lesion score, a sample size of 67 subjects (45 for the XFS group and 22 for the placebo group) would provide a statistical power of 80% to detect a mean difference of 40.以主要結局臨床皮損分數計算,67 位受試者(消風散組 45、安慰劑組 22)可有 80% 檢定力偵測 40 分的平均差異。
- 理由:論文在方法中事先說明主要結局與樣本數計算,但未提供試驗註冊或事前統計分析計畫,無法確認分析計畫在解盲前定案。
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, clinical lesion score, was the total of the erythema score plus the surface damage score. There were 4 secondary outcomes: erythema score, surface damage score, pruritus score and sleep score.主要結局為臨床皮損分數,即紅斑分數加表面損傷分數。另有 4 個次要結局:紅斑、表面損傷、搔癢與睡眠分數。
- 理由:主要結局的定義、組成與時間點(第 8 週)在方法中明確寫出,且所有預定結局在第 4、8、12 週都有報告,看不出從多種量測中挑選。
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:Because the sleep score at baseline showed a borderline nonsignificant difference between the 2 treatment groups, analysis of covariance was used to adjust the baseline sleep score for efficacy analysis.由於基線睡眠分數在兩組間呈邊緣差異,療效分析採共變數分析,校正基線睡眠分數。
- 理由:以基線睡眠分數做共變數校正是依基線資料決定,而非依結果;摘要的數值(79.7 vs 13.5)與表 3 校正後數值(79.10 vs 13.50)幾乎相同,顯示校正與否不影響結論,看不出依結果挑選分析方法。但沒有事前分析計畫可對照。