STUDY OBJECTIVE Prevent is a public health model for estimating the effect on mortality of changes in exposure to risk factors. When the model is tested by simulating a development that has already taken place, the results may differ considerably from the actual situation. The purpose of this study is to test the Prevent model by applying it to a synthetic cohort in which the development is una...

New research in asthma epidemiology in children includes the development of the ISAAC programme, which has shown large variations globally in the prevalence of asthma symptoms. Time trends in the prevalence of asthma symptoms have shown a mixed picture of increases in low prevalence centres, and a plateau or even a decrease in high prevalence centres. A range of environmental factors have been ...

Objectives: To estimate the prevalence of dysfunctional breathing in adults with asthma treated in the community. Design: Postal questionnaire survey using Nijmegen questionnaire. Setting: One general practice with 7033 patients. Participants: All adult patients aged 17–65 with diagnosed asthma who were receiving treatment. Main outcome measure: Score >23 on Nijmegen questionnaire. Results: 227...

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...