Numbered envelopes | Non-numbered envelopes | P value | |
---|---|---|---|
Returned a completed questionnaire | 30.3% (314/1038) | 35.0% (156/446) | 0.073 |
Never returned the questionnaire | 46.6% (484/1038) | 47.5% (212/446) | 0.78 |
Explicit refusals among eligible persons | 23.1% (240/1038) | 17.5% (78/446) | 0.016 |
Explicit refusals among returned envelopes | 43.3% (240/554) | 33.3% (78/234) | 0.011 |