Table 2 Interrater reliability of Newcastle–Ottawa and Jadad scales between two reviewers

  Is the case definition adequate

1

  Representativeness of the cases

1

  Selection of Controls

1

  Definition of Controls

1

  Study control

0.20 (−0.27 to 0.67)

  Any additional factor

1

  Assessment of outcome

1

  Was follow-up long enough for outcomes to occur

1

  Adequacy of follow up of cohorts

0.50 (−0.24 to 1.00)

  Randomization

1

  Blinding

1

  Withdrawal and dropouts

1