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 .
A randomized controlled trial to assess the effect of audiotaped consultations on the quality of informed consent in cardiac surgery.
OBJECTIVE To evaluate the effect of audiotaping outpatient consultations  on informed consent for cardiac surgery . DESIGN R and omized controlled trial . SETTING Tertiary health care center in Scotl and . PARTICIPANTS Eighty-four patients who had first-time coronary artery surgery conducted by 1 surgeon from February 10 , 2005 , through March 15 , 2006 , whose consultations before surgery were audiotaped . INTERVENTION R and omization to 3 trial arms . The control group ( n = 29 ) received no tape . The generic group ( n = 25 ) received a tape about coronary artery surgery , which we scripted to include information covering the domains described by the General Medical Council . The consultation group ( n = 30 ) received a tape of their consultation interview . On admission to the hospital , patients were interviewed with the Knowledge Question naire , the Multidimensional Health Locus of Control , and the Hospital Anxiety and Depression Scale . MAIN OUTCOME MEASURES The effect of audiotaping in improving the informed consent process for cardiac surgery . RESULTS The mean knowledge score of patients in the consultation group was much higher than that of the control individuals ( P < .001 ) . Patients in the consultation group reported a significantly greater sense of control with regard to their own health ( P < .001 ) and being less anxious and depressed overall . CONCLUSION Providing an audiotaped recording of the consultation before cardiac surgery appears to improve patients ' knowledge and perceptions of control of their health status and to reduce anxiety and depression . TRIAL REGISTRATION is rct n.org Identifier : IS RCT N20081026
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 .