This was eliminated by rinsing the lines between samples, separating samples with high EIA from those with low EIA, and rerunning indeterminate samples. In the majority of cases the results are either clear-cut positive or negative.
Negative samples give no bands at all.
Accepted for publication 22 June 1997. Received 26 February 1997. 3,12,13 Indeterminate results constitute a diagnostic problem and may be the cause of considerable anxiety to the examinee. Moreover, they cause difficulties to health and immigration authorities and insurance companies, resulting in delays in work permits, unnecesasry deportation or denial of insurance coverage. We have analyzed such indeterminate WB results in order to gain a better understanding of their proportion and causes under our local setting, and in order to expedite their follow-up with various referring hospitals or clinics.