The original idea was, after the cohort collections in 1948 and 1953, that the project would continue with new cohorts of students every five years. For many reasons, this has not been done, and the ongoing work can be said to be an attempt to build on the original plans.
The first collection for this project took place in the spring semester of 1980. However, the selection of individuals was made according to principles other than those applied in the Individual Statistics, as the first two cohorts were called. The population here does not consist of all individuals born in a certain year but of all students in a certain grade, more specifically of all students in 6th grade during the spring term 1980. Furthermore, the selection was carried out in two steps. First, a stratified selection of municipalities was made, after which a number of classes from the selected municipalities were sampled. In the selected classes, all students were then allowed to participate. The principles guarantee that a nationally representative sample is obtained. With this collection, Statistics Sweden became more involved and they called the project Student Panels and this cohort became Student Panel 1.
It should be pointed out that even if the selection principles differ, there are good opportunities for comparisons between the samples in the two projects, especially if the comparisons are limited to the normal-year students, that is those who at the age of thirteen attended 6th grade.
The total number of students in the sample in the spring of 1980 amounted to 9,601. Due to the refusal to participate, the sample size was reduced by 487 individuals or by 5 percent. Later, another 10 students were eliminated, so the final selection thus amounts to 9,104 students.
Planning, implementation and results from the data collection can be read in Evaluation Through Follow-up of students. A new individual statistics project (pdf downloadable from GUPEA in Swedish) and Evaluation through follow-up of students. The first data collections (pdf downloadable from GUPEA in Swedish).
In the spring of 1984, a follow-up study of the cohort was carried out, which completed its compulsory school education one year earlier. The follow-up was done with the help of a questionnaire to those who belonged to the sample (approx. 9,000) in 6th grade in the spring of 1980. Many of the questions in 1984 were similar to those given in 1980. In addition, questions were added that were only relevant after completing primary school. Just over 7,000 answered the survey in 1984.
Conduct of the survey
It has been a relatively long time since data collection for a corresponding longitudinal study was carried out. Many conditions for such collections have changed over time. Among other things, new laws that regulate the rights of participating persons in connection with investigations that require the establishment of personal registers within the meaning of the Data Act have been added. During the 1970s, the debate about the risks of using computers and the desire to limit personal register layouts has also been intense and often heated. It is reasonable that these things, together with individuals' need to have their personal integrity secured, have affected the tendency to participate in surveys of the kind that are relevant within, for example, the UGU project. Against this background, we have judged it to be valuable to have an accurate and relatively detailed account of the collection work.
The report therefore describes in some detail the various phases, from the initial information to the bodies and persons concerned to the results in the form of lists of available
and processable information in the project database. Loss of individuals and / or information is always a difficult problem in longitudinal studies. A special section in the report is therefore devoted to detailed explanations of the causes of loss and the extent of the same.