Another study carried out at the same time as the previous one but assuming a wrong hypothesis took a long time till the association with the oil was found. In fact, the researchers had to use the information collected in the other study to include questions about the oil in their questionnaires and obtain the results shown above.

Their contribution to investigation on TOS brought forward evidence to the hypothesis of associating the disease to a specific salesman.

Rigau Perez JG, Perez Alvarez L, Duenas Castro S, et al. Epidemiologic investigation of an oil-associated pneumonic paralytic eosinophilic syndrome in Spain. Am J Epidemiol 1984;119(2):250-60.