Appendix A.

Education (years) and completed vocational training*	Occupational group†	Income‡	Weighting factor
⩽10 years without training	Unskilled, semiskilled positions	Lowest quintile	1
⩽10 years with training	Skilled manual	2nd quintile	2
>12 years without training	Skilled non‐manual	3rd quintile	3
>12 years with training	Intermediate position	4th quintile	4
>12 years with college/university degree	Professional	Highest quintile	5

*Highest educational level, highest training level.

†Highest occupational grade during observation period.

‡Average individual income during observation period.