Design, conduct and analysis of surveys on work-related asthma.

Abstract

Surveys on work-related asthma serve public health investigation, research on exposure-response relations, screening for pre-clinical disease, and demonstrations of effectiveness of interventions. Hypotheses dictate survey design, which include cross-sectional, case-control, cohort and intervention studies. Tools for characterizing medical risk factors and outcomes include questionnaires, spirometry, tests of bronchial hyperreactivity, exhaled indices, induces sputum, immunological tests, ans nasal inflammatory indices. An important component of surveys is exposure assessment to compare a population to existing literature and other surveys with attention to exposure level, range, and variability among workers. Allergen exposures are challenging to characterize with respect to peak exposures and evolving immunochemical measurement methods. Exposure assessment strategies are developing rapidly for analysis of exposure-response relationships, whether for sensitization to allergens or for symptoms or diagnoses. Power calculations should guide decisions about whether to implement surveys. Research needs include surveys of populations with irritant or neutrophilic asthma and populations in damp buildings. The relevance of dermal exposure to sensitizers requires examination as a risk factor for asthma. New causes of work-related asthma may be identified by surveying industries with excess ashtma in population-based studies that do not have recognized causes of asthma.