BACKGROUND A selective, systematic, Internet-based, Chlamydia Screening Implementation for 16 to 29-year-old residents started in three regions in the Netherlands in April 2008: in the cities of Amsterdam and Rotterdam and a more rural region, South Limburg. This paper describes the evaluation design and discusses the implications of the findings from the first screening round for the analysis....

Many health and disability surveys are conducted using the non-institutionalised population as a sampling frame. Consequently, it is possible that changes in the utilisation of institutional care could account for all or part of any change in the observed prevalence of functional limitation, disability or other health state, based on samples from the non-institutionalised population. Using cond...

Two dichotomous screening tests may be compared by applying both tests to all members of a sampled population. For individuals with a positive result on either test the disease status may be verified by a reference standard, but for individuals negative on both tests the disease status may be unverified because the probability of disease is so low that further investigation is costly, unaccepta...

In visual search, 30-40% of targets with a prevalence rate of 2% are missed, compared to 7% of targets with a prevalence rate of 50% (Wolfe, Horowitz, & Kenner, 2005). This "low-prevalence" (LP) effect is thought to occur as participants are making motor errors, changing their response criteria, and/or quitting their search too soon. We investigate whether colour and spatial cues, known to impr...

A new bench-top analyzer from Du Pont, the "aca IV," was evaluated. To do so, we performed 10 different tests during an eight-week test period. The instrument is very precise (CVs less than 2%), results agree well with those obtained with the older acas (II and III), linearity is good in the clinically important ranges, and there is very little drift or carryover. From a medical-needs viewpoint...

Disease spreads as a result of people moving and coming in contact with each other. Thus the mobility patterns of individuals are crucial in understanding disease dynamics. Here we study the impact of human mobility on HIV transmission in different parts of Kenya. We build an SIR metapopulation model that incorporates the different regions within the country. We parameterise the model using cen...

To evaluate the repeatability of a questionnaire designed to assess change in respiratory symptoms 90 smokers were interviewed on two occasions. The questionnaire included questions from the Medical Research Council questionnaire on respiratory symptoms, questions on acute chest illness and cough and phlegm production in the preceding two weeks, a modification of Field's card system for estimat...

BACKGROUND Past case reports have indicated that lymphatic filariasis (LF) occurs in Zambia, but knowledge about its geographical distribution and prevalence pattern, and the underlying potential environmental drivers, has been limited. As a background for planning and implementation of control, a country-wide mapping survey was undertaken between 2003 and 2011. Here the mapping activities are ...

BACKGROUND There is increasing interest in Mycoplasma genitalium as a sexually transmissible pathogen. The clinical picture resembles that of Chlamydia trachomatis infection, but the natural course has not yet been well defined. There are no guidelines regarding who should be examined for M. genitalium. Most of the prevalence studies have been carried out in patients attending clinics for sexua...