Reliability and validity of interview data on chronic diseases. The Mini-Finland Health Survey

The Mini-Finland Health Survey was designed to obtain a comprehensive picture of health and of the need for care in Finnish adults, and to develop methods for monitoring health in the population as a whole. Out of a nationally representative sample of 8000 people aged 30 or over, 7217 (90%) were both interviewed at home by local public health nurses using simple open-ended questions and, independently of this interview, subsequently examined in a two-phase health examination. The estimate of chronic morbidity based on the health interview (56%) was close to the prevalence of definite somatic diseases diagnosed in the health examination (54%), and the agreement between the two methods was moderate (kappa = 0.53). The estimated prevalence of cardiovascular diseases was the same (23%) in the health interview and in the health examination; the agreement was substantial (kappa = 0.74). The prevalence of respiratory and musculoskeletal diseases and mental disorders was underestimated in the interview by 52, 25 and 78%, respectively; the agreement between results of the two methods was relatively low (kappa = 0.43, 0.38 and 0.30, respectively). These results suggest that both the health examination and the health interview methods, as used in this survey, have useful applications in monitoring the population's health.