Study on the effects of changes in the Dutch Disability Insurance Act (WAO), enter to the assessment of recipients of disablement insurance benefits by medical and vocational advisors Description of respondents (advisors) work / job history / job satisfaction / opinion about disability insurance rules (a.o. level of benefit, changes in rules in 1993) / (re-)assessment of hypothetical cases of disablement: ability to re-enter the labour market part-time and-or in other occupation Background variables: basic characteristics/ occupation/employment