Table 2

Inter-rater reliability for Jadad and Newcastle–Ottawa Scales: total scale scores within rater pairs

ScaleICC(2,1) (95% CI), consistency*ICC(2,1) (95% CI), absolute agreement†
Jadad—six item0.32 (0.08 to 0.53)0.32 (0.08 to 0.52)
Jadad—three item0.35 (0.11 to 0.56)0.35 (0.11 to 0.56)
Newcastle–Ottawa—cohort−0.19 (−0.63 to 0.34)−0.19 (−0.67 to 0.35)
Newcastle–Ottawa—case–control0.55 (−0.18 to 0.89)0.46 (−0.13 to 0.92)

  • ↵* ICC(2,1) where systematic differences between raters are irrelevant.

  • ↵† ICC(2,1) where systematic differences between raters are relevant.

  • ICC, intraclass correlation coefficient.