| Value | Category | 
|---|---|
| 0 | No completed individual questionnaire | 
| 1 | Age same, sex same | 
| 2 | Age same, (BH) sex different | 
| 3 | Age < 5 years different, sex same | 
| 4 | Age < 5 years different, (BH) sex different | 
| 5 | Age 5+ years different, sex same | 
| 6 | Age 5+ years different, (BH) sex different |