Abstract
This article is second translation of a GRADE series published in the BMJ to create a highly structured, transparent, and informative system for rating quality of evidence for developing recommendations. The process to develop a guideline, we should formulate a clear question with specification of all outcomes of importance to patients. Grading of Recommendations, Assessment, Development and Evaluation (GRADE) offers four levels of evidence quality: high, moderate, low, and very low for these patient-important outcomes. Randomized trials begin as high quality evidence and observational studies as low quality evidence. Although randomized trials begin as high quality evidence, quality may be downgraded as a result of study limitations (risk of bias), inconsistency (variability in results), indirectness, imprecision (wide confidence intervals), or publication bias. While the quality of evidence derived from observational studies starts at ‘low’ but may be upgraded based on a very large magnitude of effect, a dose-response gradient, and if all plausible biases would reduce an apparent treatment effect.
REFERENCES
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Table 1.
Table 2.
No of studies (no. of participants) |
Quality assessment |
Summary of findings |
|||||||
---|---|---|---|---|---|---|---|---|---|
Study limitationsa) | Consistency | Directness | Precision | Publication bias | Relative effect (95% CI)b) | Best estimate of Whipple group risk | Absolute effect (95% CI) | Quality | |
Five year mortality: | |||||||||
3 (229) | Serious limitations (-1) | No important inconsistency | Direct | No important imprecision | Unlikely | 0.98 (0.87 to 1.11) | 82.5% | 20 less/1,000; 120 less to 80 more | +++, moderate |
In-hospital mortality: | |||||||||
6 (490) | Serious limitations (-1) | No important inconsistency | Direct | Imprecision (-1)c) | Unlikely | 0.40 (0.14 to 1.13) | 4.9% | 20 less/1,000; (50 less to 10 more) | ++, low |
Blood transfusions (unit): | |||||||||
5 (320) | Serious limitations (-1) | No important inconsistency | Direct | No important imprecision | Unlikely | - | 2.45 units | -0.66 (-1.06 to -0.25); favours pylorus preservation | +++; moderate |
Biliary leaks: | |||||||||
3 (268) | Serious limitations (-1) | No important inconsistency | Direct | Imprecision (-1)c) | Unlikely | 4.77 (0.23 to 97.96) | 0 | 20 more/1,000 20 less to 50 more | ++, low |
Hospital stay (d): | |||||||||
5 (446) | Serious limitations (-1) | No important inconsistency | Direct | Imprecision (-1)c) | Unlikely | - | 19.17 days | -1.45 (-3.28 to 0.38); favours pylorus preservation | ++, low |
Delayed gastric emptying: | |||||||||
5 (442) | Serious limitations (-1) | Unexplained heterogeneity (-1)d) | Direct | Imprecision (-1)c) | Unlikely | 1.52 (0.74 to 3.14) | 25.5% | 110 more/1,000; 80 less to 290 more | +, very low |
Table 3.
Appendices
Appendix 1.
근거수준을 결정하는 요소
Appendix 2.
췌장 또는 팽대부주위 암에 대한 표준 Whipple 이자샘창자절제술과 유문 보존 이자샘창자절제술의 체계적 고찰, 메타분석을 통해 췌장암 환자의 수술적 대안의 영향에 대한 GRADE 근거요약표
연구수 (대상자수) |
근거수준 평가 |
결과요약 |
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---|---|---|---|---|---|---|---|---|---|
비뚤림 위험a) | 일관성 | 직접성 | 정밀성 | 출판비뚤림 | 상대효과 (95% CI)b) | 표준 Whipple 이자샘창자절 제술 추정치 | 절대효과 (95% CI) | 수준 | |
5년 사망률: | |||||||||
3 (229) | 심각함(-1) | 비일관성 없음 | 직접적 | 비정밀성 없음 | 가능성 적음 | 0.98 (0.87 to 1.11) | 82.5% | 1,000명당 20명 적음; 120명 적음에서 80명 많음 | +++, 중등도 |
병원내 사망률: | |||||||||
6 (490) | 심각함(-1) | 비일관성 없음 | 직접적 | 부정확(-1)c) | 가능성 적음 | 0.40 (0.14 to 1.13) | 4.9% | 1,000명당 20명 적음; 50명 적음에서 10명 많음 | ++, 낮음 |
수혈(유닛): | |||||||||
5 (320) | 심각함(-1) | 비일관성 없음 | 직접적 | 비정밀성 없음 | 가능성 적음 | - | 2.45 유닛 | -0.66 (-1.06 to -0.25); 유문 보존술식 선호 | +++; 중등도 |
담즙액 누출: | |||||||||
3 (268) | 심각함(-1) | 비일관성 없음 | 직접적 | 부정확(-1)c) | 가능성 적음 | 4.77 (0.23 to 97.96) | 0 | 1,000명당 20명 많음; 20명 적음에서 50명 많음 | ++, 낮음 |
입원기간(일): | |||||||||
5 (446) | 심각함(-1) | 비일관성 없음 | 직접적 | 부정확(-1)c) | 가능성 적음 | - | 19.17일 | -1.45 (-3.28 to 0.38); 유문보존술식 선호 | ++, 낮음 |
위 배출 지연: | |||||||||
5 (442) | 심각함(-1) | 설명되지 않는 이질성(-1)d) | 직접적 | 부정확(-1)c) | 가능성 적음 | 1.52 (0.74 to 3.14) | 25.5% | 1,000명당 110명 많음; 80명 적음에서 290명 많음 | +, 매우 낮음 |