Table 4 Scores for assessment of quality for case control studies using the Newcastle Ottawa Scale
| Â | Golse et al. 1978 | Sankar et al. 1979 | Khaleel uddin & Philpot 1980 | Rolf et al. 1993 | Visconti et al. 1994 | D'Eufe mia et al. 1995 | Yorbik et al. 2002 | Sogut et al. 2003 | Aldred et al. 2003 | James et al. 2004 | Adams et al. 2004 | James et al. 2006 | Pasca et al. 2006 | Shinohe et al. 2006 | Adams et al. 2006 | Adams et al. 2007 | Rossign ol et al. 2007 | Suh et al.2008 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1. Selection | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
Case definition | 0 | 2 | 0 | 1 | 2 | 2 | 1 | 2 | 1 | 1 | 1 | 1 | 1 | 2 | 1 | 2 | 1 | 1 |
Representativeness | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Selection of controls | 0 | 0 | 1 | 0 | 0 | 0 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 2 | 0 | 0 | 0 | 1 |
Definition of controls | 0 | 0 | 1 | 1 | 1 | 2 | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 2 | 0 | 1 | 0 | 2 |
2. Comparability | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
Control for confounding | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 1 | 0 | 2 | 0 | 0 | 2 | 0 | 0 | 0 | 0 |
3. Exposure | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
Ascertainment | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 |
Method same for cases/controls | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
Overall score | 1 | 4 | 3 | 4 | 4 | 5 | 4 | 5 | 5 | 3 | 4 | 2 | 2 | 9 | 3 | 4 | 2 | 5 |