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 .
[Different information patterns and their influence on patient anxiety prior to dental local anesthesia].
In 240 patients the correlation between different patterns of pretreatment verbal information on  local anesthesia  and perioperative patient anxiety was studied . Emphasis has been placed on the importance of " local anesthesia " itself as an anxiety factor as compared with other dental treatment measures and on legal aspects . The 240 patients were r and omized into 3 groups of 80 patients each receiving minimum , basic , or extended information on local anesthesia .  Anxiety was measured using the STAI test before and after the delivery of information , after local anesthesia , and finally after dental treatment . The significance of different anxiety factors was assessed with a question naire . Local anesthesia , pain sensation , and drilling were found to be the main anxiety factors . Higher STAI scores were observed in women and prior to surgical treatment , and the scores increased after minimum and extended information . Anxiety decreased after basic information , and significantly so in patients with high preoperative STAI scores . Disregarding the forensic aspects , our results suggest that basic information prior to dental treatment could be a useful method for reducing anxiety and improving the patients ' confidence in the dentist or surgeon
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 .