Judging the quality of evidence in reviews of prognostic factor research: adapting the GRADE framework

Table 14 Example of an adapted Grading of Recommendations Assessment, Development and Evaluation (GRADE) table for narrative systematic reviews of prognostic studies (filled in with examples of our own review illustrated in the boxes throughout this manuscript)

Outcome: Headache persistence
				Univariate			Multivariate				GRADE factors
Potential prognostic factors identified	Number of participants	Number of studies	Number of cohorts	+	0	-	+	0	-	Phase	Study limitations	Inconsistency	Indirectness	Imprecision	Publication bias	Moderate/large effect size	Dose effect	Overall quality
Headache intensity	536	3 [22–24]	3	1	2	0				1	✕	✓	✓	✓	✕	✕	✕	+
Age	867	3 [26–28]	3	1	2	0				1	✕	✕	✓	✓	✕	✕	✕	+
Type of headache diagnosis	249	3 [24, 30, 31]	3	2	1	0				1	✕	✓	✕	✓	✕	✓	✕	+
Menstruation	449	1 [22]	1	0	1	0				1	✕	✕	✕	Unclear	✕	✕	✕	+
Sex	3,272	4 [28, 38–40]	4	1	2	0	1	3	0	1	✕	✓	✓	✓	✓	✓	✕	+++
Family history of pain	654	2 [38, 44]	2	2	0	0	1	1	0	1	✓	✕	✕	✓	✕	✓	✕	+

Phase, phase of investigation. For uni- and multivariate analyses: +, number of significant effects with a positive value; 0, number of non-significant effects; -, number of significant effects with a negative value. For GRADE factors: ✓, no serious limitations; ✕, serious limitations (or not present for moderate/large effect size, dose effect); unclear, unable to rate item based on available information. For overall quality of evidence: +, very low; ++, low; +++, moderate; ++++, high.

ISSN: 2046-4053