Newcastle-Ottawa Scale
The Newcastle–Ottawa scale is a method for assessing the quality of nonrandomised studies in meta-analyses.
A maximum of 9 stars are based on:
Selection
1) Representativeness of the exposed cohort (one star)
2) Selection of the non exposed cohort (one star)
3) Ascertainment of exposure (one star)
4) Demonstration that outcome of interest was not present at start of study (one star)
Comparability
1) Comparability of cohorts on the basis of the design or analysis
a) Study controls for age (one star)
b) Study controls for any additional factor (one star)
Outcome
1) Assessment of outcome (one star)
2) Was follow-up long enough for outcomes to occur (one star)
3) Adequacy of follow up of cohorts (one star)
Reference
Jüni P, Witschi A, Bloch R, Egger M. The hazards of scoring the quality of clinical trials for meta-analysis. J.A.M.A. 1999; 282: 1054-60.
