Table 3. Kappa scores for test-retest reliability of sleep questions in the Breast Cancer Environment and Employment Study sleep questionnaire.
Usual sleep habits question (n) | Kappa | P-value |
Duration of sleep on work days (n = 192) | 0.71 | <0.001 |
Duration of sleep on non-work days (n = 192) | 0.71 | <0.001 |
Ever been diagnosed with a sleep disorder (n = 194) | 0.69 | <0.001 |
Ever taken melatonin to help you sleep (n = 192) | 0.62 | <0.001 |
Do you consider yourself a good sleeper (n = 187) | 0.74 | <0.001 |
Did you ever fall asleep with the light on (n = 187) | 0.64 | <0.001 |
- Did you usually leave it on all night (n = 66) | 0.78 | <0.001 |
Did you ever sleep with an eye mask (n = 186) | 0.45 | <0.001 |
Ever experienced periods of sleep disturbance in lifetime (n = 186) |
0.60 | <0.001 |
Number of periods of sleep disturbance in lifetime (n = 184) |
0.59 | <0.001 |