11. 観察研究SR/MAの必須事項(序論)
?既知の知見と照らし合わせて、SR/MAの理
論的根拠の説明
? なぜこの研究テーマが重要なのか?
? 既知の知見や解決されていない問題はなにか?
? 本SR/MAを実施することで何が分かるのか?
“Given the high prevalence of smoking, … tobacco
control may have a substantial importance in managing
diabetes in Japan. However, there has been no
systematic evaluation of the association between
smoking and the risk or burden of diabetes in Japan.”
Akter S et al. J Epidemiol. 2017 Dec; 27(12): 553–561.
11
12. 観察研究SR/MAの必須事項(序論)
? 研究デザイン、研究対象、曝露、アウトカ
ム、研究目的の記載
? どんなリサーチ?クエスションか?
“Therefore, the present study was performed to provide
1) a quantitative summary of the association between
smoking status (current smoking, former smoking,
smoking cessation years, and passive smoking) and the
risk of T2DM in Japan. ”
Akter S et al. J Epidemiol. 2017 Dec; 27(12): 553–561.
12
15. 観察研究SR/MAの必須事項(方法)
?適格基準
? 明快に適格基準は書かれているか?
“Inclusion criteria included prospective study design
(including prospective cohort, nested case-control, and
case-cohort studies); exposure of interest (dietary n-3
PUFAs or blood n-3 PUFAs concentrations); endpoint
(incident PCa in males); and reporting of risk estimate
(relative risk, odd ratio, or hazard ratio) of PCa with
corresponding 95% confidence intervals (CIs) for
individual n-3 PUFA exposure.”
Hu FY et al. J Epidemiol. 2015; 25(4): 261–274.
15
17. 観察研究SR/MAの必須事項(方法)
?情報源と文献検索方法
? どの情報源を用いてどの時期の文献を検索したか?
? 検索方法は再現できるように記載されているか?
“We searched two databases (PubMed and EMBASE) up
to February 2014. The search strategy was based on the
following title/abstract key words: (‘fat’ OR ‘fatty acid’
OR ‘docosahexaenoic acid’ OR ‘eicosapentaenoic acid’
OR ‘docosapentaenoic acid’ OR ‘alpha-linolenic acid’ OR
‘polyunsaturated fatty acid’ OR ‘omega-3 fatty acid’ OR
‘n-3 fatty acid’) AND (‘prostate cancer’ OR ‘prostate
neoplasms’)” Hu FY et al. J Epidemiol. 2015; 25(4): 261–274.
図書館司書や検索専門家にコンサルトするのが望ましい
17
18. 文献検索法に関する査読コメント
“You claim you have performed the study in accordance
with MOOSE. However, you do not completely fulfill the
recommendations according to the search strategy
(please recheck the MOOSE statement), e.g., the
qualifications of the searcher should be stated. Is it the
investigators, and if yes, were the search controlled with
an experienced searcher.”
図書館司書や検索専門家にコンサルトするのが望ましい
18
19. 観察研究SR/MAの必須事項(方法)
?スクリーニング、データ抽出
? どのようにして論文をスクリーニングしたか?
? どのようにしてデータを抽出したか?
“We identified articles eligible for further review by performing an
initial screen of identified abstracts or titles. The second screening
was based on the full-text review. Two investigators (SA and AG)
independently assessed the full text for eligibility; discrepancies
were resolved via consensus or determined by a third investigator
(TM). ” Akter S et al. J Epidemiol. 2017 Dec; 27(12): 553–561.
“For each included study, two authors (S.K. and H.So.) extracted
the following information relevant to study characteristics:
country, …, criteria of T2DM cases and non-cases, and used SNPs.
Inconsistencies were resolved via discussion.”
Kodama S et al. J Epidemiol. 2018; 28(1): 3–18.
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20. 観察研究SR/MAの必須事項(方法)
?個々の研究の質の評価法
? 採用された個々の研究の質(バイアス、交絡の可能
性)をどのように評価したか?
“Using the Newcastle-Ottawa Scale, we assessed the overall
quality of each study by totaling scores of the 9 criteria (0–9
stars): the representativeness of the exposed cohort, the
selection of the nonexposed cohort, ascertainment of exposure,
and outcome of interest not present at the start of the study
(maximum of 4 stars); comparability of the cohorts on the basis
of study design and analysis (maximum of 2 stars); and finally,
the assessment of the outcome (maximum of 3 stars).”
Akter S et al. J Epidemiol. 2017 Dec; 27(12): 553–561.
20
24. 観察研究SR/MAの必須事項(方法)
?要約指標と統計手法
? どの指標(リスク比、オッズ比等)で評価したか?
? MAに用いた統計手法は何か?
“Relative risks (RRs) were used as the common measure of
association across studies.”
“We used DerSimonian and Laird random-effects models for
calculating the summary estimates.”
Akter S et al. J Epidemiol. 2017 Dec; 27(12): 553–561.
“Study heterogeneity was assessed using the I2 statistic. An I2
statistic <25% indicated low heterogeneity, 25%–75% indicated
moderate heterogeneity, and >75% indicated high heterogeneity.”
Hu FY et al. J Epidemiol. 2015; 25(4): 261–274. 24
40. Take Home Message
① SR/MAはPRISMA/MOOSEに従うと書きやすい
② プロトコールを作成し、PROSPERO等に登録した
方がよい
③ 国際誌ではMEDLINE+Embaseがスタンダードで
ある
④ 文献検索法を専門家にコンサルトした方がよい
⑤ 無理にはメタする必要はない(するべきでない)
⑥ 個々の研究の批判的吟味を忘れずに行う
⑦ GRADEシステム等で研究全般のエビデンスの質
を評価することを必須とする国際誌が増えている
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41. For further readings
1. コクランハンドブック:
http://handbook.cochrane.org/front_page.htm
2. Egger, Smith, Altman “Systematic Reviews in
Health Care: Meta-Analysis in Context” (2001).
3. Borenstein et al. “Introduction to Meta-analysis”
(2009).
4. 丹後 俊郎 “新版 メタ?アナリシス入門 ─エビデン
スの統合をめざす統計手法” (2016)
5. Minds診療ガイドライン作成マニュアル 2017 m
第4章:
http://minds4.jcqhc.or.jp/minds/guideline/pdf/manual_all_2017.pdf
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