OBJECTIVE To report data relating to the informed uptake of screening tests.    SEARCH STRATEGY Electronic databases, bibliographies and experts were used to identify relevant published and unpublished studies up until August 2000.    INCLUSION CRITERIA RCTs, quasi-RCTs and controlled trials of interventions aimed at increasing the informed uptake of screening. All participants were eligible as defined by the entry criteria of individual programmes. Studies had to report actual uptake and meet three out of four criteria used to define informed uptake.   
 DATA EXTRACTION AND SYNTHESIS Relevant studies were identified, data extracted and their validity assessed by two reviewers independently. Outcome data included screening uptake, knowledge, informed decision-making and attitudes to screening. A random-effects model was used to calculate individual relative risks and 95% confidence intervals.   
 MAIN RESULTS Six controlled trials (five RCTs and one quasi-RCT), focusing on antenatal and prostate specific antigen screening, were included. All reported risks/benefits of screening and assessed knowledge. Two also assessed decision-making. Two reported risks/benefits to all randomized groups and evaluated different ways of presenting information. Neither found that interventions such as videos, information leaflets with decision trees, or touch screen computers conveyed any additional benefits over well-prepared leaflets.   
 CONCLUSIONS There is some evidence to suggest that changing the format of informed choice interventions in screening does not alter knowledge, satisfaction or decisions about screening. It is not clear whether informed choice in screening affects uptake. More well-designed RCTs are required and further research should also be directed towards the development of a valid instrument for measuring all components of informed choice in screening.
True