Table 2

Internal consistency measured for the total OHIP-NL and for its seven domains: Cronbach's alphas and average inter-item correlations


Cronbach's alpha
Average inter-item correlation

Total OHIP-NL
0.97
0.42
Functional limitation
0.82
0.34
Physical discomfort
0.87
0.42
Psychological discomfort
0.90
0.64
Physical disability
0.88
0.54
Psychological disability
0.92
0.66
Social disability
0.95
0.79
Handicap
0.92
0.65

van der Meulen et al. BMC Oral Health 2008 8:11   doi:10.1186/1472-6831-8-11