Misinterpretation of a negative test results in health screening may initiate less preventive effort and more future lifestyle-related disease. We predict that misinterpretation occurs more frequently among individuals with a low level of education compared with individuals with a high level of education.
The empirical analyses are based on unique data from a randomized controlled screening experiment in Norway, NORCCAP (NORwegian Colorectal Cancer Prevention). The dataset consists of approximately 50,000 individuals, of whom 21,000 were invited to participate in a once only screening with sigmoidoscopy. For all individuals, we also have information on outpatient consultations and inpatient stays and education. The result of health behaviour is mainly measured by lifestyle-related diseases, such as COPD, hypertension and diabetes type 2, identified by ICD-10 codes.
The results according to intention-to-treat indicate that screening does not increase the occurrence of lifestyle related diseases among individuals with a high level of education, while there is an increase for individuals with low levels of education. These results are supported by the further analyses among individuals with a negative screening test.