Cohort Profile: Burden of Obstructive Lung Disease (BOLD) study

The Burden of Obstructive Lung Disease (BOLD) study was established to assess the prevalence of chronic airflow obstruction, a key characteristic of chronic obstructive pulmonary disease, and its risk factors in adults (≥40 years) from general populations across the world. The baseline study was conducted between 2003 and 2016, in 41 sites across Africa, Asia, Europe, North America, the Caribbean and Oceania, and collected high-quality pre- and post-bronchodilator spirometry from 28 828 participants. The follow-up study was conducted between 2019 and 2021, in 18 sites across Africa, Asia, Europe and the Caribbean. At baseline, there were in these sites 12 502 participants with high-quality spirometry. A total of 6452 were followed up, with 5936 completing the study core questionnaire. Of these, 4044 also provided high-quality pre- and post-bronchodilator spirometry. On both occasions, the core questionnaire covered information on respiratory symptoms, doctor diagnoses, health care use, medication use and ealth status, as well as potential risk factors. Information on occupation, environmental exposures and diet was also collected

The targeting effectiveness of social transfers

Many methodologies exist for dividing a population into those who are classified as eligible for social transfers and those who are ineligible. Popular targeting mechanisms include means tests, proxy means tests, categorical, geographic, community-based and self-selection. This paper reviews empirical evidence from a range of social protection programmes on the accuracy of these mechanisms, in terms of minimising four targeting errors: inclusion and exclusion, by eligibility and by poverty. This paper also reviews available evidence on the various costs associated with targeting, not only administrative but also private, social, psycho-social, incentive-based and political costs. Comparisons are difficult, but all mechanisms generate targeting errors and costs. Given the inevitability of trade-offs, there is no ‘best’ mechanism for targeting social transfers. The key determinant of relative accuracy and cost-effectiveness in each case is how well the targeting mechanism is designed and implemented