3. 国際誌に掲載されたRCT
7
Results
» No significant difference (p = 0.846) was found in mean decrease in
IOP [intraocular pressure] between the SLT[selective laser
trabeculoplasty] (5.86 mm Hg) and ALT[argon laser trabeculoplasty]
(6.04 mm Hg) groups at 1 year or at any other time points...(後略)
Conclusion
» SLT is equivalent to ALT in terms of IOP lowering at 1 year, and is a
safe and effective procedure for patients with open‐angle glaucoma.
Damji et al: Br J Ophthalmol. 2006 Dec;90(12):1490-4.
科学者として
信じられるか?
審美眼 PICO-T アウトカム 質の評価 例数設計 実演 Q & A
9. GRADEシステムによる評価基準
13
研究法 エビンデンスの質
R C T → High
Moderate
R C T 以 外 → Low
Very low
降格基準
バイアスへのリスク
研究結果の不一致
外挿
広い信頼区間
出版バイアス
Guyatt G et al: J Clin Epidemiol. 2011 Apr;64(4):383-94.
昇格基準
大きな効果
用量反応性
交絡因子の調整
審美眼 PICO-T アウトカム 質の評価 例数設計 実演 Q & A
23. 臨床試験登録の主要アウトカムを参照
患者-介入-対照 (PIC) が類似の先行研究
のアウトカムと時間 (OT) を抽出
» The primary outcomes are American College of Rheumatology (ACR)
20 response at Week 14, and change from baseline in the Health
Assessment Questionnaire (HAQ) at Week 24. [Time Frame: Week 14
and Week 24]
32http://apps.who.int/trialsearch/Trial.aspx?TrialID=NCT00264550
審美眼 PICO-T アウトカム 質の評価 例数設計 実演 Q & A
34. CONSORT声明は例数設計を支持
科学的・倫理的理由から例数設計が必要
臨床的に意味のある差異を同定する十分
な検定力を有すべき
» For scientific and ethical reasons, the sample size for a trial needs to be
planned carefully, with a balance between medical and statistical
considerations. Ideally, a study should be large enough to have a high
probability (power) of detecting as statistically significant a clinically
important difference of a given size if such a difference exists.
49Moher D et al: BMJ. 2010 Mar 23;340:c869
審美眼 PICO-T アウトカム 質の評価 例数設計 実演 Q & A
39. 事例
» According to the literature [22] (類似の臨床試験を参照), the ACR20 of
patients with RA receiving leflunomide is 62.54%, while our clinical
experience (臨床感覚) puts the ACR20 of patients receiving the Xinfeng
Capsule at 79.23%. The α-value is set at 0.05 and the test power is
0.90; therefore β = 1 − 0.90 = 0.10.
54
審美眼 PICO-T アウトカム 質の評価 例数設計 実演 Q & A
Liu J et al: J Integr Med. 2013 Nov;11(6):428-34.