The European Respiratory Society study on chronic obstructive pulmonary disease (EUROSCOP): recruitment methods and strategies

Abstract

The European Respiratory Society's study on chronic obstructive pulmonary disease (EUROSCOP) is a multicentre study performed initially in 12 countries to assess the effect of 3 years' treatment with inhaled corticosteroids on lung function decline in smokers with chronic obstructive pulmonary disease (COPD). It aimed at recruiting 50 subjects in 50 European centres. This study discusses the most successful, countrywise, recruitment strategies, an important issue since many multicentre European studies may follow in the future. The total number of recruited subjects was 2147 in 39 participating centres. In total, at least 25,000 screening spirometries were performed, and about 80,000 hospital records were checked. The most effective way of recruiting subjects was to screen subjects by spirometry after mass media campaigns (eight out of nine countries). Others used workplace screenings and different types of population survey, and only a few centres successfully recruited participants by hospital records. Inclusion criteria were slightly changed upon low initial accrual rate. Initial surveys in one country, where 2405 subjects were screened by spirometry, gave an important indication for the change of the inclusion criteria. Extension of the upper age limit from 60 to 65 yr considerably improved recruitment, as did a change of the upper limit of FEV1 from below 80% predicted normal to below 100% predicted normal, while maintaining the FEV1/VC ratio below 70%. A tremendous effort is needed to recruit individuals with preclinical COPD, but this is certainly feasible with adequate strategies adjusted to each country.