Cryptosporidium parvum and Isospora belli infections among patients with and without diarrhoea.

Objective: To assess the importance of Cryptosporidium parvum and Isospora belli infections as a cause of diarrhoea among patients admitted to the Medical Wards in Queen Elizabeth Central Hospital (QECH) in Blantyre, Malawi.

Design: Prospective case control study.

Subjects: One hundred and twenty one patients with diarrhoea and 122 patients without diarrhoea.

Monitoring laboratory performance by statistical analysis of rescreening cervical smears.

The rescreening of cervical cytology smears, although inadequate both for checking the reliability of an individual screener and for the detection of false negatives, nonetheless represents an indispensable tool for assessing morphologic diagnostic criteria and monitoring laboratory performance. Interobserver and intraobserver concordance in a given laboratory determine the reliability of diagnostic criteria and disclose the possibility of improving diagnostic consistency. The various aspects of rescreening are discussed, and a simple statistical procedure for a quantitative comparison of screening reproducibility is described.