Determinants of Response in a Longitudinal Health Study Following the Firework-disaster in Enschede, The Netherlands

Abstract

Very few longitudinal health studies after disasters published data on the determinants of loss to follow up. However, these determinants provide important information for future disaster studies to improve their response and reduce selection bias. For this purpose we analyzed the data of a longitudinal health survey which was performed among residents and emergency workers, at 3 weeks (n = 3662) and at 18 months (n = 2769) after a major firework disaster in The Netherlands (Enschede, May 13, 2000). The response was lower among immigrants (54%) than among native Dutch (81%). Severe damage to the house due to the disaster (OR: 1.8; 95% CI: 1.1-3.0) and being involved as an emergency workers (OR: 2.1; 95% CI: 1.2-3.4) were associated with higher response among native Dutch, while this was not the case among immigrants. Non-western immigrants with health problems in the first study were more likely to participate in the second study (for example physical symptoms OR: 2.5: 95% CI: 1.4-4.4), while the native Dutch with these symptoms were less likely to participate (OR: 0.7; 95% CI: 0.5-0.9). In conclusion, disaster-related characteristics were associated with higher response in native Dutch. Health problems were associated with higher response among non-western immigrants and with lower response among the native Dutch.

Subjective Health Complaints Among Workers in the Aftermath of an Oil Tank Explosion

“…In a longitudinal study, the validity can also be compromised if participants are lost to follow up [114]. A rule of thumb that the loss to follow-up should not exceed 20%, has been suggested [108], but in our studies the loss to follow-up in 2012 was 29% and 28% in the studies based on proximity to the explosion site and study based on perceived smell, respectively.…”

Hyperventilation Symptoms are Linked to a Lower Perceived Health in Asthma Patients

“…Our respondents did also not reflect the ethnic diversity of the sampled South London areas adequately where Black Caribbean and Black African minorities typically constitute up to 25% of the population according to the 2001 UK Census data. Underrepresentation of men and minorities is a common problem in mailed questionnaire surveys (e.g., [50,51]). It is therefore difficult to generalize the observed associations beyond this subpopulation of primary care asthma patients or to gauge the extent to which hyperventilation symptoms are important in a general population with asthmatic disease.…”

A longitudinal comparative study of the physical and mental health problems of affected residents of the firework disaster Enschede, The Netherlands

“…Immigrants with worse health 3 weeks after the disaster were more likely to participate 18 months later. 29 These results suggest a selection bias from the first to the second survey. However, after multiple imputations were used to fill in missing data in the second survey, only minor changes were observed in the prevalence estimates of health problems.…”