most studies about laparoscopic skills acquisition are focused on the validation of simulators , i.e. , devices that recreate operative conditions . however , other important issues concerning the learning process , like feedback , are seldom discussed . this often leads to the absence of validated feedback during training . in the historical apprenticeship system of see one , do one , teach one  , feedback was directly provided during surgery in the operating room ( or ) . due to ethical and financial constraints and because of limitation of resident work hours , simulators were introduced in the last decade . this enables repeated skills training in a stress - free environment without causing harm to patients . simulators can roughly be subdivided into video box trainers and computerized virtual reality ( vr ) trainers . box trainers need the assistance of expert tutors during training sessions and courses to provide feedback . experts can provide feedback on basic laparoscopic skills ( bls ) or can guide the trainee step by step through difficult tasks , e.g. , intracorporeal knot tying , while giving tips and tricks . they can also increase motivation , which enhances the learning process , though objective assessment of the laparoscopic skills is not directly present in a traditional box trainer . on the other hand , vr trainers are programmed to give objective feedback about time , errors , and movement parameters . this implicates that several aspects of bls , for example the position of the hands and arms , will not be learned without the presence of a tutor . however , due to scarce time and relative high costs , the expert should be exploited optimally . therefore , we conducted an observational study of the role of expert feedback in laparoscopic skills acquisition during a mandatory course in residency training . in 2007 , an observational study was performed during a basic laparoscopic skills course in the netherlands . this course , named the  cobra - alpha  , is a basic laparoscopic skills course , which is mandatory for dutch obstetrics and gynecology ( ob / gyn ) residents since 1997 , and should be attended in the first or second postgraduate year ( pgy ) . the goal of this course is to train the participants in bls and provide knowledge necessary for continued training . in summary , the bls include camera navigation , body positioning , pointing and grasping tasks , and the use of the scissors . although it is an advanced task , laparoscopic knot tying is also trained as it incorporates all other bls . for the laparoscopic skills training , five validated laparoscopic box trainer exercises were used . these exercises were placing a pipe cleaner through four small circles , placing beads in the form of a b on a board , stretching out a rubber band around 16 nails on a wooden board , cutting a circle from a rubber glove and intracorporeal knot tying . the level of performance on each task was established by adding the time to completion of a task with penalty points , consequently rewarding precision and speed . additionally , the resulting score could be compared to a pre - established expert level , used as performance standard . three hours of hands - on training started after a 10-min introduction video in which the exercises were explained . consequently , one resident could hold the camera , while the other performed the exercises . although not specifically trained to teach basic laparoscopic skills , they work as consultants in teaching hospitals and have at least 5  years of experience in these skills courses . they had been instructed to guide the participants through the exercises and to provide feedback and instructions on the bls . a questionnaire was developed by the authors on the role of expert feedback in laparoscopic skills acquisition . the questionnaire consisted of a part that was handed out prior to and a part immediately after the course . in the first part , residents characteristics were collected , as well as their self - perceived level of competence on their bls . the second part concerned the expert feedback and instructions ; additionally , the self - perceived level of competence was asked again . as primary outcome measure , the expert feedback was studied . participants were asked to which extent they had perceived feedback on 13 items ( 1 = no feedback , 2 = little feedback , or 3 = extensive feedback ) . for analysis , these items were categorized in five topics : body position , camera navigation , use of instruments , laparoscopic knot tying , and other tips and tricks . furthermore , participants were asked what feedback they judged to be helpful in acquiring bls and on which topic they had desired more feedback ( multiple options were possible ) . finally , ideas or comment on the course could be noted . secondarily , the self - perceived competence was determined before and after the course in order to obtain a measure of a participant s learning effect . the self - perceived level of competence had to be rated on a visual analog scale ( vas ) . the vas ranked from unskilled to very skilled and was interpreted in the range 1 to 5 . for data analysis , a vas of 3 was chosen as cutoff point , and a score of 3 or higher was considered to be skilled . the self - perceived skills levels prior to and after the course were compared , using wilcoxon signed - rank test . the correlation coefficient between resident s experience ( expressed in number of postgraduate years ) and self - perceived skill level prior to the course was analyzed by a nonparametric spearman s rank correlation test . these exercises were placing a pipe cleaner through four small circles , placing beads in the form of a b on a board , stretching out a rubber band around 16 nails on a wooden board , cutting a circle from a rubber glove and intracorporeal knot tying . the level of performance on each task was established by adding the time to completion of a task with penalty points , consequently rewarding precision and speed . additionally , the resulting score could be compared to a pre - established expert level , used as performance standard . three hours of hands - on training started after a 10-min introduction video in which the exercises were explained . consequently , one resident could hold the camera , while the other performed the exercises . although not specifically trained to teach basic laparoscopic skills , they work as consultants in teaching hospitals and have at least 5  years of experience in these skills courses . they had been instructed to guide the participants through the exercises and to provide feedback and instructions on the bls . a questionnaire was developed by the authors on the role of expert feedback in laparoscopic skills acquisition . the questionnaire consisted of a part that was handed out prior to and a part immediately after the course . in the first part , residents characteristics were collected , as well as their self - perceived level of competence on their bls . the second part concerned the expert feedback and instructions ; additionally , the self - perceived level of competence was asked again . as primary outcome measure , participants were asked to which extent they had perceived feedback on 13 items ( 1 = no feedback , 2 = little feedback , or 3 = extensive feedback ) . for analysis , these items were categorized in five topics : body position , camera navigation , use of instruments , laparoscopic knot tying , and other tips and tricks . furthermore , participants were asked what feedback they judged to be helpful in acquiring bls and on which topic they had desired more feedback ( multiple options were possible ) . finally , ideas or comment on the course could be noted . secondarily , the self - perceived competence was determined before and after the course in order to obtain a measure of a participant s learning effect . the self - perceived level of competence had to be rated on a visual analog scale ( vas ) . the vas ranked from unskilled to very skilled and was interpreted in the range 1 to 5 . for data analysis , a vas of 3 was chosen as cutoff point , and a score of 3 or higher was considered to be skilled . the self - perceived skills levels prior to and after the course were compared , using wilcoxon signed - rank test . the correlation coefficient between resident s experience ( expressed in number of postgraduate years ) and self - perceived skill level prior to the course was analyzed by a nonparametric spearman s rank correlation test . out of the 28 participants who attended the course , 24 ( 86% ) completed the entire questionnaire . the remaining four participants had incompletely filled out the questionnaire and were excluded from further analysis . residents ranged between their first and fifth pgy ( median : pgy 3 ) . among the participants , 83% reported prior experience on a box trainer or vr trainer . the highest amount of experienced feedback was focused on laparoscopic knot tying and in some lesser extent on instrument handling ( table  1 ) . additionally , participants appraised feedback on these two topics as most valuable . less than 30% of the participants indicated to have received extensive feedback on the other topics . least attention was paid to body positioning ; 43% claimed to have received no feedback on that topic . in general , 66% of the participants thought that more feedback would have resulted in more improvement of their skills , except from feedback on camera navigation . table  1amount of experienced feedbacktopicfeedback ( % ) nolittleextensivebody positioning433621camera navigation403228instrument handling313931intracorporeal knot tying114247other tips and skills462529 amount of experienced feedback prior to the course , the median self - perceived skills assessment varied between 1.2 and 3.4 ( table  2 ) . participants already rated themselves to be skilled in camera navigation and pointing and grasping tasks prior to the course . residents who were in an earlier phase of residency , expressed in smaller number of pgy , rated their skillfulness prior to the course lower than the ones who were more experienced ( spearman s rank correlation test ,   =  0.19 , p  =  0.04 ) . in general , the self - perceived competence improved significant for laparoscopic knot tying and the use of the scissors ( wilcoxon signed - rank test , p  <  0.001 ) . table  2self - perceived skill improvementskillmedian vas scoredifference before and afterbeforeafterp valuebody positioning2.82.90.67 n.s.camera navigation3.43.20.18 n.spointing en grasping3.03.10.13 n.suse of the scissors2.73.1<0.001intracorporeal knot tying1.22.4<0.001vas : self - perceived level of competence , range 1 ( unskilled ) to 5 ( very skilled)vas visual analog scale , n.s not significantwilcoxon s signed - rank test self - perceived skill improvement vas : self - perceived level of competence , range 1 ( unskilled ) to 5 ( very skilled ) vas visual analog scale , n.s not significant wilcoxon s signed - rank test the improvement in relationship to the skill level prior to the course is shown in fig .  1 . this figure shows that participants , who rated themselves not as skilled , improved more than the already skilled participants , except for body positioning . however , six of the eight residents that scored less than 3.0 prior to the course showed improvement ( wilcoxon signed - rank test , p  =  0.06 ) . x - axis represents vas score of participant s self - perceived skills level prior to the course ; y - axis represents the skills improvement ( vas score after minus vas score before the course ) , n  =  24 participants . vas visual analog scale , in which 1 = very unskilled , 5 = very skilled skills improvement during a basic laparoscopic skills course . x - axis represents vas score of participant s self - perceived skills level prior to the course ; y - axis represents the skills improvement ( vas score after minus vas score before the course ) , n  =  24 participants . vas visual analog scale , in which 1 = very unskilled , 5 = very skilled this study revealed that residents judge feedback as a factor that positively influences their skills acquisition during a basic laparoscopic skills course . alternatively , body positioning seems to have got the least feedback , and this skill did not show improvement . admittedly , the self - perceived competence is not the most objective and accurate measure for assessment of skills level . however , in one study , residents showed to be capable to rate their own laparoscopic skills with good reliability and validity . of course , no firm conclusions can be drawn from this observational study . however , a possible relation between feedback and learning can be hypothesized . this fits the results of the study of mahmood et al . , who showed that without feedback there can be no learning . albeit , the objectives of a course need to be predefined in order to facilitate expert feedback on all training goals . though it is worrisome that in the presence of six tutors , who were informed about the learning objectives , more than 70% of the participants denied to have received extensive feedback on some basic skills ( e.g. , camera navigation and body positioning ) , a possible explanation is that the more complex tasks distract the experts attention from the more basic tasks . furthermore , the experts in the current study might be more eager to teach knot tying and cutting because they are more used to practicing and training these skills in clinical practice . this information may provide new leads for improving of the course . in the first place , tutors have to ascertain that their feedback has actually reached the trainee . secondly , it may be helpful to make the learning objectives clear to the trainees as well , to enable them to ask for more specific feedback on their skills . the improvement of self - perceived competence due to the bls course was the highest for complex tasks , i.e. , the use of scissors and intracorporeal knot tying , while residents indicated no or little improvement in the more basic skills . that reciprocates the finding that participants rated themselves better skilled in the basic than in the more complex skills . this phenomenon can be explained by the influence of feedback on a learning curve . in the beginning , the learning curve is steep and trainees experience most benefit from cognitive feedback . the cognitive feedback , which explains how and why something is performed as it should , can best be provided by experts . the positive effect that experts can generate in the start of the acquiring of motor skills was already revealed by rogers et al . . this group showed that novices have a significantly better performance on a knot tying task if expert feedback is added to computer - assisted learning . particularly , in the beginning of the process of acquiring of new skills , training courses in presence of an expert are useful . unfortunately , the residents who attended this course were not all in the beginning of residency . most participants had already trained laparoscopic skills in dry laboratories or in the or during residency . because participants obtain most benefit from the bls course in the beginning of their learning curve , residents should attend the training course early in residency . after progressing along a learning curve consequently , trainees are able to pay more attention to new elements , for example the anatomical structures during an operation . during this stage , learning relies more on intrinsic feedback , provided by sense organs and previous cognitive knowledge [ 3 , 10 ] . additionally , trainees have to become independent from external feedback . in this learning stage , feedback in the form of knowledge of results is important , instead of cognitive feedback . it can be argued whether basic skills like camera navigation , instrument handling , and body positioning require the same attention as more advanced skills like cutting and knot tying . in the aforementioned theory , every skill should be taught in an equivalent way , keeping the competence level of a trainee in mind to tailor the training to individual needs . additionally , an expert can draw parallels to or practice and , last but not least , strongly enhances the motivation of a trainee . further research needs to be done on the effect of expert feedback , in which more objective outcome measures might be used , though , with current knowledge , we can conclude that feedback plays an important role in skills acquisition and therefore the effectiveness of a training course . training objectives need to be predefined and to be clear to both tutor and trainee , in order to guide and structure the feedback . in a bls course , most benefit can be obtained at the start of the learning curve .
this study aimed to obtain insight in the effect of expert feedback during a basic laparoscopic skills training course for residents . 
 a questionnaire was held among participants regarding provided feedback and the self - perceived laparoscopic skills improvement . 
 the participants ( n  =  24 ) who completed the questionnaire were in their first to fifth postgraduate year . 
 most feedback was directed at intracorporeal knot tying ( 47% reported extensive feedback ) , while camera navigation and body positioning received the least feedback ( 40% and 43% , respectively , responded to have received no feedback at all ) . 
 after the course , the self - perceived competence in intracorporeal knot tying and cutting had improved significantly , while camera navigation , body positioning , pointing , and grasping tasks did not improve . in conclusion , 
 most benefit from expert feedback can be obtained at the start of the learning curve . 
 therefore , the basic laparoscopic skills course should be attended early in residency . 
 additionally , it is crucial that training objectives are clear prior to a course for both the expert and the trainee , in order to focus the feedback on all training objectives .