Background: In Sweden, as well as in most Western countries, sickness absence is a major public health problem that has increased in recent years. This is a complex phenomenon related not only to ill health factors, but also to other factors on the levels of the individual, the family, the workplace, and the society. Most studies of sickness absence are cross sectional, which makes it difficult to investigate aetiological factors. A longitudinal study design is preferable, because sick-leave spells can have a long duration and are often due to chronic or recurrent disorders. Objectives: The aim of the present research was to conduct a pilot study to gain further information about factors associated with sickness absence and disability pension, perceptions of contacts with rehabilitation professionals, and self-rated health over time among younger persons initially on sick leave with low-back, neck, or shoulder diagnoses. Material and methods: An eleven-year prospective cohort study of all individuals who, in 1985, were aged 25–34 years, lived in the municipality of Linköping, Sweden, and had a sick-leave spell ≥ 28 days with low-back, neck, or shoulder diagnoses (n = 213, 61% women). The following information was obtained from registers: number of sick-leave days and spells in 1982–1984; diagnosis and demographical data in 1985 (age, sex, occupation, citizenship, marital status, and income); data on each sick-leave period (date, full/part time), disability pension (date, diagnoses, temporary/permanent, full/part time); emigration (date), and death (date, cause) from 1985 to 1 September 1996. In 1996, a questionnaire was sent to members of the cohort (response rate 73%). Different measures were used to analyse sickness absence and disability pension over the eleven-year period, possible risk factors for disability pension were tested by Cox regression, and possible factors predicting future low levels of sickness absence were tested by logistic regression. Based on the questionnaire perceptions of encounters with rehabilitation professionals were analysed with factor analyses and linear regression, and the so called health-line (a method to collect data on self-rated health over time) was tested, and the results were compared with data on sickness absence and disability ension. Results: The members of the cohort turned out to be a high-risk group for disability pension. After 11 years, 26% of the women and 14% of the men had been granted such benefits, mainly due to musculoskeletal diagnoses, but also with psychiatric diagnoses for half of the men and 17% of the women. Full-time pension was granted more often to men than to women. The women had higher levels of sickness absence. An extended Cox regression model proved suitable for prediction of disability pension. Taking citizenship and long-term sickness absence into consideration, the women had a 1.9 times higher risk of being granted disability pension than the men. Predictors for future low levels of sickness absence were a history of low sickness absence, having a white-collar job, and being married. These associations were not discerned when a pathogenic approach was used, which implies that factors other than the opposite risk factor for disability pension are associated with future low sickness absence. Three dimensions of the individuals’ contacts with professionals were identified: supportive treatment, distant treatment, and empowering treatment. Women perceived both social insurance officers and health care professionals as more supportive than the men did. Contact with social insurance officers was experienced as more supportive and empowering by persons on disability pension than by those not receiving such benefits. Data collected using the health-line (i.e., self-rated health from 1985 to 1995) was correlated with data on annual mean number of sick-leave days and days on disability pension. No tendency to recall bias was noted. Conclusions: Additional research is needed to elucidate the situation of women on sick leave with low-back, neck, and shoulder diagnoses. Further testing and practical application of statistical and epidemiological models for analysing sickness absence and disability pension data should be carried out to ascertain the validity and usefulness of such models. / On the day of the public defence the status of the article I was: Submitted; article III was: Accepted; article IV was: Submitted and article V was: In press.