Sample of the LASA data collection

The initial sample was weighted according to expected mortality at mid-term within each sex and age group, so that after five years equal numbers of men and women were expected to be alive in the ages 55-59, 60-64, 65-69, 70-74, 75-79, and 80-85 years. This design was expected to provide sufficient opportunity for multivariate research and for obtaining adequate subsamples for special studies. In addition, it should leave sufficient participants to be examined after a period of 10 years.

Municipal registries provided the sampling frame. The sample was constructed so as to reflect the national distribution of urbanization and population density. The sample was based in three culturally distinct geographical areas in the West, North-East, and South of the Netherlands. Each area consists of one middle- to large-size city and two or more rural municipalities which border on the city. The municipalities included in the sample are: Amsterdam, Wormerland, Waterland (three municipalities in the West), Zwolle, Ommen, Genemuiden, Zwartsluis, Hasselt (North-East), and Oss, Uden, Boekel (South). Within follow-up observations, subjects who moved out of the municipality were traced and re-interviewed.

LASA uses the sample of the NESTOR-program "Living arrangements and social networks of older adults" (LSN). This is essentially a cross-sectional study, with follow-up of specific smaller subsamples. While LASA is designed as an interdisciplinary project with potentially policy relevant outcomes, the main purpose of LSN is the development of theory and methods for the study of living arrangements and social networks in old age.

To be able to distinguish age, cohort and period effects, in 2002 a new cohort (birth years 1938-1947) has been sampled from the same sampling frame as the original cohort.

Composition of the realized sample (number of respondents) with respect to year of birth

Year of birth

Wave A
(LSN)

Wave B
(LASA)

Wave C
(LASA)

Wave D
(LASA)

Wave E
(LASA)

Wave F
(LASA)

Wave G
(LASA)

 

1992

1992-1993

1995-1996

1998-1999

2001-2002

2005-2006

2008-2009

1903-1907

689

.

.

.

.

.

.

1908-1912

774

580

384

233

133

42

16

1913-1917

712

575

431

318

215

109

63

1918-1922

589

472

384

313

242

160

105

1923-1927

593

492

441

386

335

278

216

1928-1932

580

512

463

416

385

330

284

1933-1937

557

476

442

410

381

338

301

Total

4494

3107

2545

2076

1691

1257

985

 

Wave A/B
(LASA)

.

.

.

.

Wave F
(LASA)

Wave G
(LASA)

 

2002-2003

.

.

.

.

2005-2006

2008-2009

1938-1942

508

.

.

.

.

459

411

1943-1947

494

.

.

.

.

449

422

Total

1002

.

.

.

.

908

833