[Tuberculosis screening coverage of immigrants: marked attrition in follow-up screenings]

To estimate the coverage of bi-annual follow-up screening for tuberculosis amongst immigrants, excluding asylum seekers.

Retrospective cohort study.

Participation in bi-annual chest X-ray screening during the first 18 months was recorded for immigrants who underwent entry screening in 1996 in the following Dutch municipal health services (MHS's): Zuid-Kennemerland (Haarlem), Flevoland (Lelystad), Midden-Brabant (Tilburg) en West-Friesland (Hoorn). The number of immigrants that had left the country before the subsequent screening was taken into account in the Zuid-Kennemerland MHS data on screening coverage.

Of the 2147 immigrants who underwent entry screening in 1996 (48% men and 52% women; 68% aged 15-34 years), 1075 (50%; range: 29-76) returned for the first follow-up screening and 620 (29%; 21-61) returned for the second. In MHS Zuid-Kennemerland, 113 of the 777 immigrants who had a chest X-ray at entry had left the country before the first follow-up screening, and another 89 had left before the second. Of the remaining persons, who were probably still in the Netherlands, 454 (68%; 454/777 = 58%) returned for the first follow-up screening, and 166 (29%; 166/777 = 21%) returned for the second.

The coverage of screening for tuberculosis in immigrants decreased after the obligatory entry screening, even when corrected for those who left the country.