Background: Declining response rates are a common challenge to epidemiological research. Response rates further are particularly low among young people. We thus aimed to identify factors associated with health survey response among young employees using different data collection methods. Methods: We included fully register-based data to identify key socioeconomic, workplace and health-related factors associated with response to a health survey collected via online and mailed questionnaires. Additionally, telephone interviews were conducted for those who had not responded via online or to the mailed survey. The survey data collection was done in autumn 2017 among young employees of the City of Helsinki, Finland (18-39 years, target population n=11,459). Results: The overall response to the survey was 51.5% (n=5898). The overall findings suggest that differences in the distributions of socioeconomic, workplace and health-related factors between respondents in the online or mailed surveys, or telephone interviews, are relatively minor. Telephone interview respondents were of lower socioeconomic position, which helped improve representativeness of the entire cohort. Despite the general broad representativeness of the data, some socioeconomic and health-related factors contributed to response. Thus, non-respondents were more often men, manual workers, from the lowest income quartile, had part-time jobs, and had more long sickness absence spells. In turn, job contract (permanent or temporary) and employment sector did not affect survey response. Conclusions: Despite a general representativeness of data of the target population, socioeconomically more disadvantaged and those with long sickness absence, are slightly overrepresented among non-respondents. This suggests that when studying the associations between social factors and health, the associations can be weaker than if complete data were available representing all socioeconomic groups.

Objectives To examine the impact of recurrent, as compared with single, reports of back pain on exit from paid employment over decades of follow-up. Methods The study sample was from the British Whitehall II Study cohort (n=8665, 69% men, aged 35-55 at baseline), who had provided information about their reports of back pain between 1985 and 1994. Data about exit from paid employment (health-related and non-health related exit, unemployment and other exit) were collected between 1995 and 2013. Repeated measures logistic regression models were fitted to examine the associations, and adjust for covariates. Results Recurrent pain was reported by 18% of participants, while 26% reported pain on an occasion and 56% did not report pain. Report of back pain on an occasion was not associated with health-related job exit, whereas recurrent pain was associated with such an exit (OR 1.51; 95% CI 1.15 to 1.99), when compared with those who did not report pain. These associations were somewhat stronger among middle-grade and lower-grade employees, while these associations were not seen among higher-grade employees. Differences in associations by age and psychosocial working conditions were small. Conclusions These results highlight the need for early detection of recurrent back pain to prevent exit out of paid employment for health reasons. As the risk varies by occupational grade, this emphasises the importance of identification of high-risk groups and finding ways to address their modifiable risk factors.

Objectives We examined developmental trajectories of multisite musculoskeletal pain in midlife, and their associations with mental well-being. Methods Midlife municipal employees at baseline aged 40, 45, 50, 55 or 60 years (80% women) from the City of Helsinki, Finland, responded to a baseline questionnaire in 2000-02 (N = 8,960; response rate 67%) and follow-ups in 2007 (N = 7,332; 83%) and 2012 (N = 6,809; 78%). Trajectories of the number of pain sites (0-4) were modelled using latent class growth analysis (n = 6,527). Common mental disorders were assessed by the General Health Questionnaire (GHQ) 12-item version (trichotomized to low, intermediate or high). Information on health-related behaviour, comorbidity and socioeconomic position was obtained from the questionnaire. Associations of baseline factors with pain trajectories were assessed by multinomial logistic regression. Results We identified four distinct pain trajectories: high (15%), increasing (24%), decreasing (20%) and low (41%). After an initial increase, the high and increasing trajectories stabilized at around 2.5 and 1.5 pain sites respectively. In a multivariable model, high, increasing and decreasing trajectories of pain sites were associated with higher baseline GHQ scores. The association was strongest for the high trajectory (low GHQ: OR 3.7, 95% CI 2.8-4.9; high GHQ: OR 5.4, 95% 4.4-6.6). Trajectory membership also associated with unhealthy behaviours, musculoskeletal comorbidities and a low socioeconomic position at baseline. Average GHQ was consistently highest for the high pain trajectory and decreased in the decreasing trajectory over the follow-up. Conclusions Multisite musculoskeletal pain shows variable developmental patterns among midlife employees. The trajectories are associated with the level of common mental disorders. Significance Four developmental trajectories of multisite pain in midlife were described over 10-12 years of follow-up: low (41% of the sample), increasing (24%), high (15%) and decreasing (20%). Common mental disorders strongly associated with these. Belonging to the highest tertile of mental disorders at baseline increased the risk of membership in the high trajectory more than fivefold. On the other hand, together with a decrease in mental disorders, the number of pain sites decreased to zero.

Background: Early exit from paid employment is a notable public health and societal challenge. Previous research has largely focused on the relationships among variables instead of the relationships among individuals with different work participation history. Person-oriented methods enable to identify latent groups of individuals who are likely to follow similar development in their work participation over time. We thus aimed to identify work participation trajectories during early and midlife careers and their social determinants using large nationally representative data comprising over 1 million initially employed individuals and a 10-year follow-up for their work participation. A further aim was to determine the cumulative incidence of sickness absence due to key diagnostic groups, mental disorders and musculoskeletal diseases within the trajectories. Methods: Young (25-38 years at baseline, n = 495,663) and midlife (39-52 years at baseline, n = 603,085) Finnish people, all working in 2004, were followed up through 2013, with registers of the Social Insurance Institution, and the Statistics Finland. The registers provided data for work participation and its determinants, as well as for computing the cumulative incidence of sickness absence. Latent class growth analysis was used to identify trajectories. Results: Three distinctive trajectories were identified: temporary exit, permanent exit, and continuously employed people. As compared to the other trajectories, those belonging to the permanent exit trajectory were more likely men, manual workers and had a lower income. The cumulative incidence of sickness absence due to mental disorders was highest in the permanent exit trajectory group. For musculoskeletal diseases, the cumulative incidence of sickness absence increased in the permanent exit trajectory mainly in the older age groups. Conclusion: Distinct group-based trajectories of early work exit can be identified in a representative cohort of initially employed people. Focusing on the determinants of premature exit and early intervention to tackle increasing sickness absence may promote work participation particularly in the most vulnerable groups.