Kostråd for å fremme folkehelsen og forebygge kroniske ... - NRK

4. Prinsipper og metodologi som ligger til grunn for de norske kostrådene
Faktaboks 4.7. Kategorisering basert på The Scottish Intercollegiate Guideline Network (SIGN)
SIGN statements of evidence
Ia Evidence obtained from meta-analysis of randomized controlled trials
Ib Evidence obtained from at least one randomized controlled trial
IIa Evidence obtained from at least one well-designed controlled study without
randomization
IIb Evidence obtained from at least one other type of well-designed quasi-experimental study
III Evidence obtained from well-designed non-experimental descriptive studies, such as
comparative studies, correlation studies and case studies
IV Evidence obtained from expert committee reports or opinions and/or clinical experiences
of respected authorities
SIGN grades of recommendations
A Requires at least one randomised controlled trial as part of a body of litterature of overall
good quality and consistency adressing the specific recommendations. (Evidence levels
Ia, Ib)
B Requires the availability of well conducted clinical studies but no randomised clinical
trials on the topic of recommendation. (Evidence levels IIa, IIb, III)
C Requires evidence obtained from expert committee reports or opinions and/or clinical
experiences of respected authorities. Indicates and absence of directly applicable clinical
studies of good quality. (Evidence level IV)
For å konvertere disse kategoriene til World Cancer Research Fund kategorier er det benyttet
følgende konvertering:
• Overbevisende årsakssammenheng = Level A
• Sannsynlig årsakssammenheng = Level B
• Mulig årsakssammenheng = Level C
• Årsakssammenheng usannsynlig = Level A og B
Rapporten fra European Association for the Study of Diabetes (EASD) fra 2004 (35) har benyttet
SIGN-metodologien og kategoriseringen i faktaboks 4.7. Konklusjonene fra denne kunnskapsoppsummeringen
er benyttet ved utarbeidelse av norske kostråd. Konklusjonene konvertert til World
Cancer Research Fund matriser er gitt nedenfor.
33