Related Experiment Video
Updated: Aug 7, 2026

Applying an eMASS Customization Program as a Research Tool to Evaluate Consumer Benefits
Published on: September 27, 2019
Does it make sense to do repeated surveys?--the Lundby Study, 1947-1997
P Nettelbladt1, M Bogren, C Mattisson
1Department of Clinical Neuroscience, Division of Psychiatry, The Lundby Study, Lund University Hospital, Lund, Sweden. per.nettelbladt@psykiatr.lu.se
Objective:
To describe the Lundby Study and the difficulties in doing repeated surveys.
Method:
Best-estimate consensus diagnoses have been used since 1957 together with DSM-IV and ICD-10 in 1997.
Results:
The Lundby population consisting of 3563 probands was investigated in 1947, 1957 and 1972. Sufficient information was available for 98-99%. In 1997-2000 a fourth field investigation was carried out. Attrition rate for the interviews was 13% (238/1797). About 36% (1030/2827) had died between 1972 and 1997, but data from registers, case notes and key-informants for the period 1972 and 1997 completed the information for 94% (2659/2827). The population has followed the same pattern of development as many rural populations in Sweden since the 1940s. Multiple sources of information are preferable in longitudinal studies in order to tackle the problem of changing diagnostic systems.
Conclusion:
Low attrition rates over 50 years and reasonable diagnostic uniformity make comparisons over time justifiable.
Related Concept Videos
Surveys
Longitudinal Research
Cross-Sectional Research
Data Collection by Observations
An astronomer viewing the motion and brightness of stars in the sky and recording the data is an example of observational data collection. A botanist recording...
Observational Studies
There are three types of observational studies – Prospective, retrospective, and cross-sectional.
Prospective Study
Prospective studies, also known as longitudinal or cohort studies, are carried out by collecting future data from groups sharing similar characteristics. One example of...
Longitudinal Studies

