Data was collected by means of telephone interview and web-based (or postal) questionnaire. The gross sample consisted of individuals above age 50 who participated in NorLAG1 and/or NorLAG2. The response rate was higher among women than men, and higher among the younger than the older.
Of the 9000, more than 6000 persons (74%) completed the questionnaire.
We appreciate the effort of everyone involved in the data collection, particularly by the respondents and the interviewers. Thank you!