This review concluded, based on limited data, that informed choice interventions can increase acquisition of relevant knowledge and enhance informed choice above usual care but do not affect screening uptake. The review's reliability is unclear given the lack of reporting of key elements of the review process.

To assess the effectiveness of prescreening interventions in enhancing informed choice.

MEDLINE, EMBASE, PsycINFO and CINAHL were searched from 2000 to February 2010 for peer-reviewed studies published in English. Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials (CENTRAL) and NRR were searched. Reference lists of all identified studies were searched. Search terms were reported.

Studies were included if they were randomised controlled trials (RCTs) conducted between 1 January 2000 (following publication of a prior systematic review) and 30 March 2010. Eligible participants were adults (aged 18 years and over) contacted about participating in a screening test. Participants in one trial arm needed to receive a prescreening intervention aimed at improving informed choice. The primary outcome was informed choice (measures documented in the paper). Secondary outcomes included knowledge, attitudes, intentions and uptake.

Included studies considered interventions on informed choice about a screening test for one of three types of cancer (prostate, colorectal and breast) or diabetes. Interventions used enhanced leaflets, decision aids, videos and internet materials. Half of the trials that assessed informed choice used the Multidimensional Measure of Informed choice (MMIC) and half used unvalidated measures. Both studies that assessed decisional conflict used the validated Decisional Conflict Scale (DCS).

The authors did not state how many reviewers selected studies.

Risk of bias was assessed with consideration of randomisation methods, allocation concealment, blinding of investigators, participant baseline characteristics, follow-up rate, use of intention-to-treat analysis, use of validated measures and intervention fidelity.

The authors did not state how many reviewers assessed study quality.

Data were extracted on whether the intervention increased or decreased informed choice, decisional conflict, knowledge, attitudes, intentions and uptake of screening or whether there was no difference between intervention and control groups.

The authors did not state how many reviewers extracted data for the review.

Studies were synthesised narratively.

Eight RCTs were included in the review. All eight RCTs used computer-generated randomisation, seven concealed intervention allocation from participants, five had blinded investigators, all had equivalent baseline characteristics and a follow-up rate of over 80% and five used validated measures to assess primary outcomes. Three studies analysed data with intention-to-treat analysis. Two studies showed intervention fidelity and the fidelity of six could not be determined from study descriptions. Follow-up ranged from immediately to 12 months.

Compared to usual care or a no education control, informed choice improved using the enhanced prescreening interventions in five out of eight trials. Two trials that assessed decisional conflict as an indirect measure of informed choice showed no difference in decisional conflict between treatment groups. Knowledge acquisition increased in seven out of eight trials. Changes in attitudes towards screening varied across the trials: two found no change, two found decreased positive attitudes towards prostate screening (as intended by the intervention), one found decreased positive attitudes towards faecal occult blood screening (not as intended by the intervention) and one resulted in more positive attitudes towards screening for breast cancer (as intended). Most interventions resulted in no change in screening intentions or uptake, where measured.

Based on limited data, informed choice interventions can increase acquisition of relevant knowledge and enhance informed choice above usual care but do not affect screening uptake.

This review was based on defined inclusion criteria and was underpinned by a search of several relevant databases. Only peer-reviewed publications in English were eligible and this opened the review up to language and publication biases. Quality was assessed but results of quality assessment were not presented in full. The authors did not state whether more than one reviewer was involved in the study selection, data extraction and quality assessment; duplicate processes would help minimise bias and error. A narrative synthesis was appropriate given the diversity of the studies.

The review's reliability is unclear given the highlighted concerns.

Practice: The authors stated that the most promising prescreening interventions to enhance knowledge and informed choice may be decision aids. They stated that their limited evidence suggested that increasing informed choice did not affect screening uptake.

Research: Not stated

Intramural Research Program, National Human Genome Research Institute, National Institutes of Health, USA.

Jepson RG, Forbes CA, Sowden AJ, Lewis RA. Increasing informed uptake and non-uptake of screening: evidence from a systematic review. Health Expect. 2001; 4(2): 116-126.

This is a critical abstract of a systematic review that meets the criteria for inclusion on DARE. Each critical abstract contains a brief summary of the review methods, results and conclusions followed by a detailed critical assessment on the reliability of the review and the conclusions drawn.