We have identified efforts by research ers to investigate interventions which seek to improve information delivery and consideration of information to enhance  informed consent .
The interventions used consistently improve patient knowledge , an important prerequisite for informed consent .
This is encouraging and these measures could be widely employed although we are not able to say with confidence which types of interventions are preferable .
Our results should be interpreted with caution due to the high levels of heterogeneity associated with many of the main analyses although we believe there is broad evidence of beneficial outcomes for patients with the pragmatic application of interventions .
BACKGROUND Achieving informed consent is a core clinical procedure and is required before any surgical or invasive procedure is undertaken .
However , it is a complex process which requires patients be provided with information which they can underst and and retain , opportunity to consider their options , and to be able to express their opinions and ask questions .
There is evidence that at present some patients undergo procedures without informed consent being achieved .
OBJECTIVES To assess the effects on patients , clinicians and the healthcare system of interventions to promote informed consent for patients undergoing surgical and other invasive healthcare treatments and procedures .
AUTHORS ' CONCLUSIONS Informed consent is an important ethical and practical part of patient care .
Information seeking and interactive videodisc preparation for third molar extraction.
Patient response to interactive videodisc preparation for third molar extraction surgery was examined as a function of self-reported information-seeking style . Amount learned was compared among patients informed via an interactive videodisc , noninteractive videotape of the same material , or surgeon only .  Anxiety levels and satisfaction with preparation were compared between the videodisc and videotape groups . At consultation , patients ( n = 35 ) were r and omly assigned to either the disc- or the tape-viewing group . First , subjects completed a demographic survey , state anxiety scale , quiz on knowledge about third molars and surgery risks and complications , and information-seeking scales . Immediately after viewing the video , subjects completed another anxiety scale and a multiple-choice quiz covering the material presented . Subsequently , another 25 patients undergoing the routine ( surgeon-only ) consultation procedure were given the same multiple-choice quiz following consultation . Quiz scores differed significantly among the groups ; mean percent correct for the tape-viewing subjects was 85 ; for disc-viewing subjects 72.6 ; for surgeon-only subjects , 40 . Self-rated information seeking was unrelated to amount of video viewed by disc subjects ( on average , 64 % of the videodisc was viewed ) , and disc subjects who rated themselves higher in information-seeking achieved the lowest postpreparation quiz scores . Subjects in the disc group were significantly more satisfied with the amount of preparation than the tape group . Although disc group subjects were significantly less knowledgeable following consultation than were tape group subjects , interactive videodisc preparation for third molar extraction appears to have some advantages over more traditional approaches . Further research is needed to determine whether this approach to preparing patients is suitable for widespread clinical use
We have identified efforts by research ers to investigate interventions which seek to improve information delivery and consideration of information to enhance  informed consent .
The interventions used consistently improve patient knowledge , an important prerequisite for informed consent .
This is encouraging and these measures could be widely employed although we are not able to say with confidence which types of interventions are preferable .
Our results should be interpreted with caution due to the high levels of heterogeneity associated with many of the main analyses although we believe there is broad evidence of beneficial outcomes for patients with the pragmatic application of interventions .
BACKGROUND Achieving informed consent is a core clinical procedure and is required before any surgical or invasive procedure is undertaken .
However , it is a complex process which requires patients be provided with information which they can underst and and retain , opportunity to consider their options , and to be able to express their opinions and ask questions .
There is evidence that at present some patients undergo procedures without informed consent being achieved .
OBJECTIVES To assess the effects on patients , clinicians and the healthcare system of interventions to promote informed consent for patients undergoing surgical and other invasive healthcare treatments and procedures .
AUTHORS ' CONCLUSIONS Informed consent is an important ethical and practical part of patient care .