Laparoscopic versus small-incision cholecystectomy : Health status in a blind randomised trial Background Gallstones are a major cause of morbidity , and cholecystectomy is a commonly performed procedure . Minimal invasive procedures , laparoscopic cholecystectomy -LRB- LC -RRB- and small-incision cholecystectomy -LRB- SIC -RRB- , have replaced the classical open cholecystectomy . No differences have been found in primary outcome measures between LC and SIC , therefore secondary outcome measures have to be considered to determine preferences . The aim of our study was to examine health status applying evidence-based guidelines in LC and SIC in a randomised trial . Cholecystectomy is a commonly performed procedure in patients with symptomatic cholecystolithiasis . With an estimated incidence up to 2.17 per thousand inhabitants -LSB- 1 , 2 -RSB- , and 500,000 cholecystectomies performed annually in the USA -LSB- 3 -RSB- and 21,000 in The Netherlands -LRB- an incidence of 1.31 per thousand inhabitants -RRB- -LSB- 4 , 5 -RSB- , gallstones are a major cause of morbidity in the Western world . During the 1980s , the preferred surgical technique for cholecystectomy changed from the classical open procedure to a smaller incision approach -LSB- 6 , 7 -RSB- and eventually to laparoscopic cholecystectomy . Although evidence of superiority was never delivered , the laparoscopic technique was accepted as the gold-standard procedure by consensus -LSB- 3 -RSB- . Multiple randomised trials comparing laparoscopic -LRB- LC -RRB- and small-incision cholecystectomy -LRB- SIC -RRB- have been performed and results are inconsistent . Some favour the SIC technique , others favour the LC technique , and many take a neutral position . All these randomised trials are included in our Cochrane review . Our review showed no differences in primary outcome measures between LC and SIC -LSB- 8 -RSB- . In comparing -LRB- surgical -RRB- treatments , primary outcome measures -LRB- mortality and severe complications -RRB- have to be considered prior to secondary outcome measures . As no significant differences between LC and SIC in primary outcome measures were found -LSB- 8 -RSB- , it is justified to consider health status , an important secondary outcome measure . Frequently , quality of life is confused with health status . Quality of life measures the subjective judgment of patients about their condition , while health status refers to the impact of disease on patients ' lives in the physical , psychological and social domains . Questionnaires , both generic and condition-specific , have been shown to be useful in measuring changes in health status after cholecystectomy -LSB- 9 -- 11 -RSB- . Several studies showed that health status was improved , both after LC and open cholecystectomy in patients suffering socially disabling uncomplicated symptomatic cholecystolithiasis -LSB- 12 -- 14 -RSB- . Differences between the open and laparoscopic technique are not clear -LSB- 15 -RSB- , although some studies found superior results using the laparoscopic technique -LSB- 16 , 17 -RSB- . To date , differences in health status between LC and SIC are not very well examined -LSB- 18 -- 20 -RSB- . Moreover , as the previous studies did not use the appropriate questionnaires as advised by evidence-based guidelines , there had been no possibility to correctly find differences in health status between both operating techniques . The gastrointestinal quality of life index -LRB- GIQLI -RRB- and the short form -LRB- SF-36 -RRB- are frequently used and validated questionnaires -LRB- disease-specific and generic , respectively -RRB- and are most suitable for evaluating patients ' functional recovery after cholecystectomy -LSB- 21 -RSB- . Objective The aim of our study was to examine differences in health status in patients with symptomatic cholecystolithiasis before and after LC and SIC in a blinded randomised clinical trial . We used the GIQLI and the SF-36 questionnaires , as recommended by evidence-based guidelines -LSB- 21 -RSB- . Methods All patients with symptomatic cholecystolithiasis visiting the outpatients clinic of the St. Elisabeth hospital in Tilburg were considered for inclusion in a blind randomised trial comparing laparoscopic and small-incision cholecystectomy . Verbal and written informed consent was obtained from each patient , and patients were consecutively listed for elective cholecystectomy . Health status was a secondary outcome measure as part of the randomised clinical trial . Sample size No differences in primary outcome measures -LRB- mortality and complications -RRB- were expected between LC and SIC -LSB- 8 -RSB- . Consequently , a secondary outcome measure should be used to decide on preferences between both techniques . We decided to focus on costs between both techniques as the most important secondary outcome measure . Based on an anticipated difference of 10 % in direct costs 120 patients had to be included in each group . However , multiple outcome measures including health status were evaluated in this randomised trial . Based on a previous study -LSB- 18 -RSB- , it was calculated that 128 patients were needed in each group to detect a difference of 5 points -LRB- assuming a standard deviation of 20 -RRB- in the gastrointestinal quality-of-life index -LRB- GIQLI -RRB- questionnaire with a type I error of 0.05 and a power of 0.8 . Randomisation As randomised trials with high bias risk may overestimate intervention effects -LSB- 22 -RSB- , results of randomised trials with low bias risk are considered more reliable . Therefore , attention is warranted for correct generation of the allocation sequence , allocation concealment , blinding , and follow-up . A random-number table was used for the generation of the allocation sequence and allocation concealment was guaranteed by using sealed envelopes . To eliminate bias caused by preoperative expectations , patients were randomised in the operation theatre after induction of anaesthesia . A telephone call to the secretary office was made and an employee opened an envelope . All patient data were recorded in a case record form , with the procedure reported as ` trial cholecystectomy ' . Wounds and port sites were dressed with identical opaque dressings , stained using iodine , regardless of the surgical procedure performed , to allow blinding for patient , nurses , and physicians during the postoperative period . The type of operation was revealed just before discharge . No patients were lost to follow-up . Operative procedures were standardised apart from using a laparoscopic or small-incision technique . Anaesthesia , postoperative care and analgesic use were also standardised . Inclusion and exclusion criteria Inclusion criteria were : male or female patients with symptomatic cholecystolithiasis , age 18 years or older at recruitment , with reasonable to good health according to American Society of Anaesthesiologists -LRB- ASA -RRB- classification -LRB- ASA I or II -RRB- -LSB- 23 -RSB- , no known relevant allergies and a signed letter of informed consent . Exclusion criteria were : age younger than 18 years , choledocholithiasis -LRB- icterus , acholic faeces and/or bilirubine twice normal range -RRB- , cholangitis , known pregnancy , moderate to severe systemic disease -LRB- ASA III and higher -RRB- , known cirrhosis of the liver , history of abdominal malignancy , previous upper abdominal surgery -LRB- precluding laparoscopic approach -RRB- , psychiatric disease , or another reason -LRB- e.g. lack of knowledge of the Dutch language -RRB- for making follow-up or completion of questionnaires unreliable . Obesity was indexed but not considered an exclusion criterion -LSB- 24 -RSB- . Recovery after successful endoscopic treatment of choledocholithiasis was not a contraindication . Acute cholecystitis is a different disease with other complication rates , morbidity , and conversion rates , and patients suffering acute cholecystitis were , therefore , not included . Surgical procedures The policy in our hospital was not to perform operative cholangiography in any patient in elective cholecystectomy . All patients had nasogastric intubations during the operation that were removed immediately afterwards . Bladder drainage was not performed . Abdominal wall and skin closure were standardised . In case of technical difficulties or for safety reasons , both laparoscopic and small-incision cholecystectomies were converted to open cholecystectomy by a subcostal incision -LRB- > 8 cm -RRB- . Reasons for conversion were registered . The wounds were covered with standard wound dressings as described by Majeed -LSB- 24 -RSB- to blind patient and ward personnel postoperatively . We did not use any local anaesthetic technique into the wounds nor intercostal nerve blocks . Laparoscopic cholecystectomy Open introduction of trocars was performed in all patients , regardless of previous abdominal surgery . Pneumoperitoneum was created using the subumbilical trocar with an intra-abdominal pressure up to 12 mmHg . Three trocars for instruments were inserted . The dissection of the cystic artery and cystic duct , identifying Calot 's triangle , was performed using a three-point ` flag ' technique -LSB- 25 -RSB- . The cystic duct and artery were clipped and transsected . After complete dissection of the gallbladder , it was removed either through the subumbilical or the subxyphoidal trocar . Fascia defects as a result of the insertion of 10 mm trocar and the open introduction of the subumbilical trocar were closed with UR6 vicryl 1.0 / 2.0 ® sutures . All instruments , except for the subumbilical trocar , were reusable . No suction drains were left in the subhepatic space at the end of the procedure . Small-incision cholecystectomy In the literature most authors used 8 cm -LRB- or less -RRB- as a cut-off point to differentiate between small-incision and open cholecystectomy -LSB- 24 , 26 -- 32 -RSB- . Therefore , we performed small-incision cholecystectomy principally through an incision of 6 cm , maximally extended to 8 cm . As part of a separate research question , all patients had a preoperative ultrasound scan and the location of the fundus of the gallbladder was marked on the skin . We used the craniocaudal position of the mark for incision . The mediolateral position of the mark was not used , because in the pilot phase we found that the incision would be too lateral for adequate view of the hilus . The incision was placed over the musculus rectus abdominis . Only standard instruments were used and no special equipment . Access to the peritoneum was obtained by a muscle splitting -LRB- and not transsection -RRB- technique of the musculus rectus abdominis -LRB- like in an open appendectomy -RRB- . The gallbladder was dissected by a fundus-first technique . If necessary the gallbladder was punctured to remove its liquid contents . The cystic duct and artery were ligated and the gallbladder was removed . No suction drains were left in the subhepatic space at the end of the procedure . Posterior and anterior fascias were closed separately with PDS 3.0 ® running suture . After wound closure , the length of the incision was measured . When the length exceeded 8 cm , the operation was considered to be a conversion to open cholecystectomy . Postoperative protocol Early oral intake and mobilization were encouraged . Patients left the hospital as soon as they felt capable . As patients were admitted at the day of operation , hospital stay was defined as the number of nights -LRB- postoperative -RRB- in hospital . Shortly before discharge , wound dressings were removed for wound inspection . For logistic reasons , we were not able to blind the surgeon at the patients ' follow-up . Follow-up took place according to a standardised scheme after 2 weeks , 6 weeks , and 3 months . Patients were encouraged to resume work and normal daily activity as soon as they felt capable to do so . Measurements In accordance with evidence-based guidelines -LSB- 21 -RSB- , we decided to use the generic short form -LRB- SF-36 -RRB- and the disease-specific gastrointestinal quality-of-life index -LRB- GIQLI -RRB- questionnaires . These questionnaires were completed preoperatively , on the first day postoperative and at each follow-up visit after 2 and 6 weeks and after 3 months . In addition , the body image questionnaire -LRB- BIQ -RRB- was completed preoperatively and at 6 weeks postoperatively in order to estimate differences in the patients ' perception of their body image and cosmetics -LSB- 33 -RSB- . The SF-36 is a generic health status questionnaire that has 36 questions to assess eight domains -LRB- physical functioning , role physical , bodily pain , general health , vitality , social functioning , role emotional and mental health -RRB- -LSB- 34 -RSB- . Internal consistency measured by Cronbach 's alpha was shown to be high -LRB- above 0.80 in all subscales -RRB- -LSB- 34 -RSB- . The Dutch version has been validated -LSB- 35 -RSB- . The GIQLI is a disease-specific health status measure . It includes both specific questions on gastrointestinal symptoms , for both the upper and the lower gastrointestinal tract , as well as questions on physical , emotional and social capabilities -LSB- 36 -RSB- . It is a mixed questionnaire that includes both generic and specific questions . Based on face validity , five subscales are distinguished in addition to a total score . Internal consistency measured by Cronbach 's alpha was shown to be high -LRB- above 0.90 in all subscales -RRB- -LSB- 36 -RSB- . The Dutch version has been validated -LSB- 37 -RSB- . The body image questionnaire -LRB- BIQ -RRB- consists of nine questions evaluating three subscales : body image , cosmetic , and self-confidence . The BIQ has shown to consist of two factors , a body image and a cosmetic factor -LSB- 33 -RSB- . The body image scale measures patients ' perception of and satisfaction with their own body and explores patients ' attitudes toward their bodily appearance . The cosmetic scale assesses the degree of satisfaction of patients with respect to the physical appearance of the scar . Additionally , a question is added to assess patients ' self-confidence before and after surgery . Internal validity -LRB- measured by Crohnbach 's alpha -RRB- reliability coefficients were shown to be high for both the body image -LRB- 0.80 -RRB- and cosmetic scales -LRB- 0.83 -RRB- -LSB- 33 -RSB- . Statistical analysis Analyses were performed according to the type of operative procedure used , based on the intention to treat principle . Apart from this main analysis , one subgroup analysis was performed : converted procedures -LRB- LC and SIC -RRB- were compared with minimal invasive procedures -LRB- LC and SIC -RRB- . This subgroup analysis was performed in order to illustrate the sensitivity of the questionnaires . Calculations were made using SPSS version 11.0 ® . Repeated measures analysis of variance -LRB- ANOVA -RRB- was used to evaluate health status differences over time between the two operative techniques . Additional independent t-tests were performed to test for time-specific differences in scores at the preoperative measurements between two groups in order to check for a correct randomisation procedure . If appropriate , additional independent t-tests were performed to test for other time-specific differences in measurements . Results All trial patients were included and operated between January 2001 and March 2004 . Leaving unwilling and excluded patients out of consideration , 366 patients initially fulfilled the inclusion criteria and were initially included in the trial . A total of 102 patients were not randomised for a variety of reasons -LRB- Fig. 1 -RRB- . After randomizing 264 patients , another seven patients were excluded -LRB- after their cholecystectomy -RRB- for the following reasons : unwillingness for further participation in the trial -LRB- 2 -RRB- , intraoperative suspicion of malignancy -LRB- 2 -RRB- , transfer to another ward not participating in the trial -LRB- 1 -RRB- , participation in two trials -LRB- not in line with the Helsinki declaration -RRB- -LRB- 1 -RRB- , and insufficient knowledge of the Dutch language -LRB- 1 -RRB- . Excluding the data of these seven patients from our analyses did not affect the results of our questionnaires in any way . A total of 257 patients were left for analysis -LRB- LC : 120 and SIC : 137 -RRB- . Fig. 1Revised consort statement diagram showing the flow of participants through each stage of the randomised trial -LSB- 38 -RSB- Baseline characteristics and operative results The groups -LRB- LC and SIC -RRB- did not differ regarding age , sex , body mass index -LRB- BMI -RRB- and ASA classification -LRB- Table 1 -RRB- . The classical diagnostic symptoms of cholecystolithiasis as well as the duration of these symptoms were also equally distributed in both groups . In addition , the number of patients presenting with complicated gallstone disease who had received treatment by endoscopic retrograde cholangiopancreaticography -LRB- ERCP -RRB- -LRB- and papillotomy -RRB- were equally distributed and operated on in a later stage -LRB- Table 2 -RRB- . Table 1Patient characteristicsLaparoscopic cholecystectomy -LRB- n = 120 -RRB- Small-incision cholecystectomy -LRB- n = 137 -RRB- P valueMale31 -LRB- 25.8 % -RRB- 30 -LRB- 21.9 % -RRB- 0.459 Female89 -LRB- 74.2 % -RRB- 107 -LRB- 78.1 % -RRB- Age -LRB- years -RRB- Mean -LRB- SD -RRB- 48.4 -LRB- 14.1 -RRB- 48.5 -LRB- 14.0 -RRB- 0.974 Median -LRB- range -RRB- 49 -LRB- 17 -- 77 -RRB- 48 -LRB- 18 -- 80 -RRB- BMI Mean -LRB- SD -RRB- 27.5 -LRB- 4.8 -RRB- 27.9 -LRB- 4.6 -RRB- 0.500 Median -LRB- range -RRB- 26.8 -LRB- 18.5 -- 45.9 -RRB- 27,2 -LRB- 18.0 -- 43.3 -RRB- ASA stage I81 -LRB- 67.5 % -RRB- 91 -LRB- 66.4 % -RRB- 0.855 II39 -LRB- 32.5 % -RRB- 46 -LRB- 33.6 % -RRB- BMI body mass index ; ASA american society of anaesthesiologists classificationTable 2Operative features and difficulties of laparoscopic and small-incision cholecystectomyLaparoscopic cholecystectomy -LRB- n = 120 -RRB- Small-incision cholecystectomy -LRB- n = 137 -RRB- P valuePatients with complicated gallstone diseases before cholecystectomy18180 .668 Endoscopic retrograde cholangiopancreaticography12130 .890 Duration of symptoms -LRB- weeks -RRB- n = 107 -LRB- 89.2 % -RRB- n = 130 -LRB- 94.9 % -RRB- 0.443 mean -LRB- SD -RRB- 61.1 -LRB- 108.8 -RRB- 70.3 -LRB- 147.2 -RRB- median -LRB- range -RRB- 26 -LRB- 2 -- 884 -RRB- 17.5 -LRB- 1 -- 1040 -RRB- Incision length -LRB- mm -RRB- # n = 95 -LRB- 12 conversions -RRB- n = 134 -LRB- 20 conversions -RRB- 0.196 mean -LRB- SD -RRB- 76.1 -LRB- 33.8 -RRB- 76.0 -LRB- 24.0 -RRB- median -LRB- range -RRB- 65 -LRB- 40 -- 200 -RRB- 66 -LRB- 49 -- 165 -RRB- Inflammation21250 .876 Operative team : surgeon -- resident15 -LRB- 12.5 % -RRB- 21 -LRB- 15.3 % -RRB- 0.515 resident -- surgeon84 -LRB- 70.0 % -RRB- 100 -LRB- 73.0 % -RRB- 0.596 resident -- resident21 -LRB- 17.5 % -RRB- 18 -LRB- 13.1 % -RRB- 0.331 Hospital stay * mean -LRB- SD -RRB- 2.4 -LRB- 4.6 -RRB- 3.1 -LRB- 12.4 -RRB- 0.560 median -LRB- range -RRB- 1 -LRB- 1 -- 36 -RRB- 2 -LRB- 1 -- 144 -RRB- Hospital stay * -LRB- without one extreme value -RRB- mean -LRB- SD -RRB- 2.1 -LRB- 3.38 -RRB- 2.04 -LRB- 2.42 -RRB- 0.877 Employed -LRB- n -RRB- 5051Return to work -LRB- weeks -RRB- mean -LRB- SD -RRB- 4.1 -LRB- 2.3 -RRB- 3.7 -LRB- 2.0 -RRB- 0.298 median -LRB- range -RRB- 4 -LRB- 1 -- 12 -RRB- 3 -LRB- 0.5 -- 12 -RRB- # conversions were included in incision length measurements * hospital stay in postoperative nights There was no mortality . There were five intraoperative complications in the LC group compared with three in the SIC group . There were 16 postoperative complications in the LC group and 13 in the SIC group . There were 21 and 16 total complications -LRB- intra - and postoperative -RRB- in the LC and SIC group , respectively . Of these , 11 and 7 complications were serious in the LC and the SIC group , respectively -LRB- Table 3 -RRB- . We did not find a difference in the number or severity of the complications . Table 3Serious complications in laparoscopic and small-incision cholecystectomy -LRB- intraoperative and postoperative -RRB- Laparoscopic cholecystectomy11Small-incision cholecystectomy7Intraoperative complicationsAsystole 1Cardiac ischemia , no elevated enzymes 1Common bile duct -LRB- CBD -RRB- injury , eventually hepatico-jejunostomy , complicated prolonged ICU stay , stenosis bile duct .1 CBD injury , conversion , T-drain , ERCP and papillotomy for CBD stone1Bleeding requiring conversion -LRB- and transfusion -RRB- 1Hepatic parenchyma rupture , conservative treatment -LRB- transfusion -RRB- 1Bowel injury at introduction -LRB- sutured -RRB- 1Cerebrovascular accident at recovery1Total intraoperative5Total intraoperative3Postoperative complicationsPneumonia1Cystic duct leakage -LRB- ERCP + stent -RRB- 1Cerebrovascular accident -LRB- 6 weeks postoperative -RRB- 1CBD injury , multiple relaparotomies and ICU stay 1Intra-abdominal fluid collection -LRB- haematoma -RRB- ; icterus -LRB- ERCP : no stones , complicated by bleeding -RRB- 1CBD stone -LRB- ERCP -RRB- and abscess intra-abdominal -LRB- ultrasound drainage -RRB- 1Pancreatitis -LRB- conservative treatment -RRB- 1CBD stone with pancreatitis -LRB- ERCP -RRB- 1Intra-abdominal abscess -LRB- re-laparoscopy -RRB- 1Epididimitis -LRB- operation by urologist -RRB- 1Total postoperative6Total postoperative4CBD common bile duct ; ICU intensive care unit ; ERCP endoscopic retrograde cholangiopancreaticography Operative time was shorter for SIC compared to LC -LRB- 60 versus 72 min , respectively ; U = 6013.0 , p < 0.001 -RRB- . Conversion rates were similar -LRB- p = 0.312 -RRB- , with similar reasons for conversion . The follow-up rate between the groups was not statistically different . Follow-up was 91.4 -- 96.3 % at six weeks , 82.2 -- 82.8 % at three months and 100 % at either six weeks or three months . Complaints at follow-up were comparable . There were no differences in the preoperative measurements of the SF-36 subscales , all the GIQLI subscales , the total GIQLI score and the BIQ subscales . Health status The questionnaires were obtained with a response rate varying from 87.5 % preoperatively to 77.4 % three months postoperatively . The nonresponders did not differ from those who remained in the study with regard to complications -LRB- 16 % -RRB- , operative time -LRB- 65 minutes -RRB- , hospital stay -LRB- 1.5 days -RRB- , return to work -LRB- 3.2 weeks -RRB- or baseline scores . When comparing LC with SIC -LRB- intention-to-treat -RRB- , we found no differences in all SF-36 subscales , except for ` perceived health change ' . There were significant differences favouring the laparoscopic technique -LRB- F = 16.054 , df = 1 ; p < 0.001 -RRB- -LRB- Table 4 -RRB- . Performing time-specific analyses , differences were identified at two weeks -LRB- p = 0.029 -RRB- and six weeks -LRB- p < 0.001 -RRB- postoperatively . There were no differences between LC and SIC with regard to the four GIQLI subscales , the total GIQLI score , and the body image subscales . Table 4Comparison of GIQLI , SF-36 and BIQ scores in laparoscopic -LRB- LC -RRB- and small-incision cholecystectomy -LRB- SIC -RRB- according to intention-to-treat -LRB- mean scores and SD -RRB- PreoperativePostoperativeP valueday 12 weeks6 weeks12 weeksSF-36PhysicalLC77.0 -LRB- 23.0 -RRB- 57.1 -LRB- 29.5 -RRB- 67.5 -LRB- 23.2 -RRB- 83.2 -LRB- 21.2 -RRB- 87.8 -LRB- 17.4 -RRB- 0.413 SIC83 .0 -LRB- 18.3 -RRB- 39.9 -LRB- 29.8 -RRB- 63.0 -LRB- 22.8 -RRB- 83.1 -LRB- 20.8 -RRB- 87.5 -LRB- 19.3 -RRB- SocialLC43 .4 -LRB- 14.2 -RRB- 77.8 -LRB- 19.9 -RRB- 70.7 -LRB- 23.9 -RRB- 86.5 -LRB- 19.3 -RRB- 91.9 -LRB- 15.9 -RRB- 0.260 SIC42 .7 -LRB- 17.1 -RRB- 74.3 -LRB- 22.6 -RRB- 66.3 -LRB- 25.8 -RRB- 82.3 -LRB- 22.9 -RRB- 90.4 -LRB- 19.0 -RRB- Role physicalLC56 .4 -LRB- 43.4 -RRB- 52.6 -LRB- 43.2 -RRB- 26.7 -LRB- 36.4 -RRB- 67.4 -LRB- 40.1 -RRB- 81.1 -LRB- 34.9 -RRB- 0.667 SIC60 .8 -LRB- 44.4 -RRB- 53.0 -LRB- 45.7 -RRB- 29.5 -LRB- 49.4 -RRB- 54.8 -LRB- 42.6 -RRB- 79.2 -LRB- 35.8 -RRB- Role emotionLC73 .7 -LRB- 39.4 -RRB- 70.5 -LRB- 38.8 -RRB- 68.3 -LRB- 41.7 -RRB- 82.7 -LRB- 33.6 -RRB- 88.6 -LRB- 27.8 -RRB- 0.797 SIC74 .3 -LRB- 39.7 -RRB- 70.3 -LRB- 40.7 -RRB- 66.4 -LRB- 54.9 -RRB- 80.7 -LRB- 36.5 -RRB- 88.7 -LRB- 29.4 -RRB- MentalLC61 .7 -LRB- 11.8 -RRB- 75.0 -LRB- 17.1 -RRB- 77.3 -LRB- 18.3 -RRB- 83.3 -LRB- 16.2 -RRB- 85.1 -LRB- 16.6 -RRB- 0.558 SIC62 .0 -LRB- 10.9 -RRB- 72.1 -LRB- 18.9 -RRB- 74.5 -LRB- 18.7 -RRB- 81.2 -LRB- 18.4 -RRB- 83.4 -LRB- 17.4 -RRB- VitalityLC54 .1 -LRB- 11.0 -RRB- 59.6 -LRB- 22.4 -RRB- 52.1 -LRB- 21.1 -RRB- 67.8 -LRB- 20.1 -RRB- 73.5 -LRB- 20.4 -RRB- 0.767 SIC53 .8 -LRB- 12.2 -RRB- 58.4 -LRB- 22.9 -RRB- 51.8 -LRB- 21.6 -RRB- 66.9 -LRB- 22.6 -RRB- 72.7 -LRB- 21.7 -RRB- PainLC56 .5 -LRB- 19.5 -RRB- 55.6 -LRB- 22.5 -RRB- 52.2 -LRB- 21.7 -RRB- 74.7 -LRB- 20.2 -RRB- 82.4 -LRB- 21.5 -RRB- 0.429 SIC54 .6 -LRB- 17.1 -RRB- 55.9 -LRB- 24.6 -RRB- 46.4 -LRB- 21.9 -RRB- 69.3 -LRB- 23.8 -RRB- 83.1 -LRB- 21.4 -RRB- General healthLC56 .1 -LRB- 11.7 -RRB- 69.7 -LRB- 17.3 -RRB- 71.8 -LRB- 19.3 -RRB- 74.9 -LRB- 22.0 -RRB- 76.3 -LRB- 21.2 -RRB- 0.457 SIC57 .4 -LRB- 11.3 -RRB- 65.1 -LRB- 19.2 -RRB- 70.1 -LRB- 20.1 -RRB- 72.5 -LRB- 21.5 -RRB- 76.4 -LRB- 19.2 -RRB- Health changeLC57 .7 -LRB- 21.2 -RRB- 57.7 -LRB- 21.2 -RRB- 62.0 -LRB- 26.9 -RRB- 76.7 -LRB- 23.9 -RRB- 77.1 -LRB- 24.4 -RRB- < 0.001 * SIC55 .4 -LRB- 20.4 -RRB- 55.4 -LRB- 20.4 -RRB- 53.5 -LRB- 27.5 -RRB- 64.6 -LRB- 25.1 -RRB- 71.5 -LRB- 27.2 -RRB- GIQLIPhysicalLC2 .79 -LRB- 0.76 -RRB- 2.82 -LRB- 0.73 -RRB- 2.78 -LRB- 0.75 -RRB- 3.20 -LRB- 0.62 -RRB- 3.31 -LRB- 0.59 -RRB- 0.790 SIC2 .95 -LRB- 0.74 -RRB- 2.67 -LRB- 0.83 -RRB- 2.69 -LRB- 0.75 -RRB- 3.14 -LRB- 0.73 -RRB- 3.30 -LRB- 0.63 -RRB- GastrointestinalLC3 .01 -LRB- 0.59 -RRB- 3.01 -LRB- 0.54 -RRB- 3.22 -LRB- 0.48 -RRB- 3.46 -LRB- 0.41 -RRB- 3.50 -LRB- 0.42 -RRB- 0.247 SIC3 .12 -LRB- 0.58 -RRB- 3.13 -LRB- 0.55 -RRB- 3.22 -LRB- 0.45 -RRB- 3.46 -LRB- 0.46 -RRB- 3.52 -LRB- 0.40 -RRB- SocialLC2 .89 -LRB- 0.48 -RRB- 2.82 -LRB- 0.42 -RRB- 2.81 -LRB- 0.52 -RRB- 2.93 -LRB- 0.37 -RRB- 2.97 -LRB- 0.29 -RRB- 0.056 SIC2 .90 -LRB- 0.42 -RRB- 2.82 -LRB- 0.43 -RRB- 2.76 -LRB- 0.56 -RRB- 2.85 -LRB- 0.50 -RRB- 2.85 -LRB- 0.38 -RRB- MentalLC2 .55 -LRB- 0.55 -RRB- 2.59 -LRB- 0.45 -RRB- 2.88 -LRB- 0.41 -RRB- 3.04 -LRB- 0.35 -RRB- 3.07 -LRB- 0.37 -RRB- 0.561 SIC2 .65 -LRB- 0.49 -RRB- 2.58 -LRB- 0.55 -RRB- 2.74 -LRB- 0.45 -RRB- 2.99 -LRB- 0.47 -RRB- 3.04 -LRB- 0.44 -RRB- TotalLC102 .4 -LRB- 17.0 -RRB- 102.6 -LRB- 14.8 -RRB- 108.5 -LRB- 15.0 -RRB- 116.4 -LRB- 11.9 -RRB- 118.3 -LRB- 11.7 -RRB- 0.607 SIC106 .7 -LRB- 14.9 -RRB- 104.5 -LRB- 16.0 -RRB- 107.4 -LRB- 14.0 -RRB- 116.7 -LRB- 13.2 -RRB- 118.0 -LRB- 11.1 -RRB- BIQBody imageLC6 .42 -LRB- 1.98 -RRB- -- -- 6.03 -LRB- 1.90 -RRB- -- 0.530 SIC6 .26 -LRB- 1.89 -RRB- -- -- 5.85 -LRB- 1.35 -RRB- -- CosmeticLC -- -- -- 18.38 -LRB- 3.88 -RRB- -- 0.100 SIC -- -- -- 17.52 -LRB- 3.55 -RRB- -- Self-confidenceLC6.95 -LRB- 1.27 -RRB- -- -- 7.68 -LRB- 1.21 -RRB- -- 0.647 SIC7 .02 -LRB- 1.28 -RRB- -- -- 7.49 -LRB- 1.15 -RRB- -- * significant difference Subgroup analysis In checking for differences in preoperative data in the minimal invasive procedures versus conversions comparison , we only found a significant difference in the self-confidence subscale of the body image questionnaire -LRB- t = 2.821 , df = 207 , p = 0.005 -RRB- with higher self-confidence scores in the minimal invasive operated group -LRB- 7.08 versus 6.31 -RRB- . No other differences were found in preoperative data . In order to assess differences between minimal invasive procedures -LRB- both laparoscopic and small-incision -RRB- and procedures converted to the classical open cholecystectomy , we examined patients ' scores across the follow-up period -LRB- Table 5 -RRB- . Table 5Comparison of GIQLI , SF-36 and BIQ scores in minimal invasive laparoscopic -LRB- LC -RRB- and small-incision cholecystectomy -LRB- SIC -RRB- procedures versus converted -LRB- LC and SIC -RRB- procedures -LRB- mean scores and SD -RRB- PreoperativePostoperativeP valueday 12 weeks6 weeks12 weeksSF-36Physicalmin-inv79.9 -LRB- 21.3 -RRB- 50.1 -LRB- 30.9 -RRB- 67.3 -LRB- 22.1 -RRB- 83.5 -LRB- 21.1 -RRB- 87.6 -LRB- 18.9 -RRB- 0.046 * conv82 .3 -LRB- 17.5 -RRB- 31.6 -LRB- 24.9 -RRB- 45.5 -LRB- 22.6 -RRB- 79.6 -LRB- 19.3 -RRB- 87.8 -LRB- 14.6 -RRB- Socialmin-inv43.2 -LRB- 15.5 -RRB- 76.7 -LRB- 21.3 -RRB- 69.9 -LRB- 24.1 -RRB- 85.1 -LRB- 20.9 -RRB- 90.9 -LRB- 18.1 -RRB- 0.214 conv41 .7 -LRB- 18.3 -RRB- 70.1 -LRB- 21.9 -RRB- 55.1 -LRB- 29.0 -RRB- 76.1 -LRB- 24.7 -RRB- 93.2 -LRB- 13.8 -RRB- Role physicalmin-inv60.2 -LRB- 43.4 -RRB- 54.0 -LRB- 44.5 -RRB- 27.9 -LRB- 36.3 -RRB- 61.3 -LRB- 41.7 -RRB- 79.9 -LRB- 35.2 -RRB- 0.415 conv46 .9 -LRB- 46.8 -RRB- 43.1 -LRB- 43.9 -RRB- 31.0 -LRB- 87.6 -RRB- 55.0 -LRB- 44.1 -RRB- 81.8 -LRB- 37.1 -RRB- Role emotionmin-inv74.9 -LRB- 39.0 -RRB- 72.1 -LRB- 38.8 -RRB- 67.4 -LRB- 41.5 -RRB- 82.1 -LRB- 34.6 -RRB- 89.3 -LRB- 28.1 -RRB- 0.373 conv66 .7 -LRB- 42.8 -RRB- 56.5 -LRB- 45.4 -RRB- 66.7 -LRB- 93.7 -RRB- 76.7 -LRB- 40.6 -RRB- 83.3 -LRB- 32.1 -RRB- Mentalmin-inv61.8 -LRB- 11.6 -RRB- 73.8 -LRB- 17.9 -RRB- 76.6 -LRB- 17.5 -RRB- 82.7 -LRB- 16.4 -RRB- 84.9 -LRB- 15.9 -RRB- 0.413 conv62 .6 -LRB- 9.1 -RRB- 70.8 -LRB- 19.5 -RRB- 69.0 -LRB- 25.5 -RRB- 77.1 -LRB- 24.4 -RRB- 78.6 -LRB- 23.8 -RRB- Vitalitymin-inv54.0 -LRB- 11.9 -RRB- 59.5 -LRB- 22.8 -RRB- 53.1 -LRB- 21.1 -RRB- 67.8 -LRB- 21.4 -RRB- 73.3 -LRB- 20.6 -RRB- 0.180 conv53 .2 -LRB- 8.8 -RRB- 55.0 -LRB- 21.2 -RRB- 41.6 -LRB- 21.1 -RRB- 63.3 -LRB- 21.6 -RRB- 71.1 -LRB- 24.9 -RRB- Painmin-inv55.6 -LRB- 18.4 -RRB- 56.5 -LRB- 23.7 -RRB- 50.4 -LRB- 22.1 -RRB- 72.5 -LRB- 22.3 -RRB- 82.9 -LRB- 21.7 -RRB- 0.038 * conv55 .2 -LRB- 17.7 -RRB- 49.6 -LRB- 22.2 -RRB- 37.1 -LRB- 17.4 -RRB- 65.4 -LRB- 22.4 -RRB- 81.9 -LRB- 18.5 -RRB- General healthmin-inv56.8 -LRB- 11.4 -RRB- 68.2 -LRB- 18.1 -RRB- 72.0 -LRB- 19.4 -RRB- 74.2 -LRB- 21.3 -RRB- 76.9 -LRB- 19.7 -RRB- 0.136 conv56 .3 -LRB- 12.4 -RRB- 59.7 -LRB- 19.6 -RRB- 61.0 -LRB- 20.2 -RRB- 67.8 -LRB- 25.1 -RRB- 72.2 -LRB- 23.3 -RRB- Health changemin-inv56.8 -LRB- 20.8 -RRB- 56.8 -LRB- 20.8 -RRB- 58.8 -LRB- 27.5 -RRB- 71.7 -LRB- 24.9 -RRB- 74.9 -LRB- 26.3 -RRB- 0.066 conv54 .2 -LRB- 20.4 -RRB- 54.2 -LRB- 20.4 -RRB- 46.3 -LRB- 24.7 -RRB- 56.3 -LRB- 24.2 -RRB- 67.1 -LRB- 23.6 -RRB- GIQLIPhysicalmin-inv2.90 -LRB- 0.72 -RRB- 2.78 -LRB- 0.76 -RRB- 2.79 -LRB- 0.71 -RRB- 3.19 -LRB- 0.65 -RRB- 3.33 -LRB- 0.60 -RRB- 0.007 * conv2 .67 -LRB- 0.96 -RRB- 2.40 -LRB- 0.96 -RRB- 2.20 -LRB- 0.87 -RRB- 2.96 -LRB- 0.91 -RRB- 3.10 -LRB- 0.71 -RRB- Gastrointestinalmin-inv3.09 -LRB- 0.57 -RRB- 3.10 -LRB- 0.54 -RRB- 3.23 -LRB- 0.47 -RRB- 3.47 -LRB- 0.43 -RRB- 3.52 -LRB- 0.39 -RRB- 0.052 conv2 .89 -LRB- 0.68 -RRB- 2.89 -LRB- 0.56 -RRB- 3.08 -LRB- 0.37 -RRB- 3.42 -LRB- 0.50 -RRB- 3.46 -LRB- 0.50 -RRB- Socialmin-inv2.89 -LRB- 0.46 -RRB- 2.83 -LRB- 0.42 -RRB- 2.83 -LRB- 0.51 -RRB- 2.90 -LRB- 0.43 -RRB- 2.92 -LRB- 0.35 -RRB- 0.003 * conv2 .90 -LRB- 0.35 -RRB- 2.75 -LRB- 0.45 -RRB- 2.35 -LRB- 0.62 -RRB- 2.74 -LRB- 0.58 -RRB- 2.85 -LRB- 0.35 -RRB- Mentalmin-inv2.60 -LRB- 0.53 -RRB- 2.58 -LRB- 0.50 -RRB- 2.84 -LRB- 0.41 -RRB- 3.04 -LRB- 0.38 -RRB- 3.06 -LRB- 0.38 -RRB- 0.031 * conv2 .63 -LRB- 0.45 -RRB- 2.64 -LRB- 0.53 -RRB- 2.48 -LRB- 0.57 -RRB- 2.81 -LRB- 0.70 -RRB- 2.96 -LRB- 0.63 -RRB- Totalmin-inv104.9 -LRB- 16.0 -RRB- 104.3 -LRB- 15.0 -RRB- 108.9 -LRB- 14.3 -RRB- 117.1 -LRB- 11.5 -RRB- 118.4 -LRB- 11.0 -RRB- 0.020 * conv101 .4 -LRB- 17.0 -RRB- 97.8 -LRB- 17.8 -RRB- 98.5 -LRB- 13.3 -RRB- 111.2 -LRB- 19.5 -RRB- 115.8 -LRB- 14.0 -RRB- BIQBody imagemin-inv6.31 -LRB- 1.80 -RRB- -- 5.75 -LRB- 1.27 -RRB- - < 0.001 * conv6 .60 -LRB- 2.78 -RRB- -- 7.55 -LRB- 3.04 -RRB- - Cosmeticmin-inv -- 18.27 -LRB- 3.54 -RRB- - < 0.001 * conv -- 14.86 -LRB- 3.97 -RRB- - Self-confidencemin-inv7.08 -LRB- 1.16 -RRB- -- 7.60 -LRB- 1.13 -RRB- -0.064 conv6 .31 -LRB- 1.83 -RRB- -- 7.38 -LRB- 1.60 -RRB- - * significant difference ; min-inv : minimal invasive procedures -LRB- LC and SIC -RRB- ; conv : converted procedures -LRB- LC and SIC -RRB- There were significant differences in the SF-36 subscales ` physical functioning ' -LRB- F = 4.057 , df = 1 ; p = 0.046 -RRB- and ` pain ' -LRB- F = 4.391 , df = 1 ; p = 0.038 -RRB- . In the GIQLI questionnaire , there were significant differences in the total score -LRB- F = 5.593 , df = 1 ; p = 0.020 -RRB- , and in the ` physical ' -LRB- p = 0.007 -RRB- , ` social ' -LRB- p = 0.003 -RRB- , and ` mental ' -LRB- p = 0.004 -RRB- subscales . Also , in the BIQ there were significant differences in the ` body image ' and ` cosmetic ' subscales between both operative groups , favouring the minimal invasive procedures -LRB- F = 13.939 , df = 1 ; p < 0.001 -RRB- . No other differences were found . Discussion We have used both generic and disease-specific health status questionnaires and a body image questionnaire to evaluate the effect of LC versus SIC in patients having cholecystectomy for symptomatic cholecystolithiasis . No differences were found between laparoscopic and small-incision cholecystectomies -LRB- applying intention-to-treat -RRB- . However , with regard to minimal invasive or converted procedures , we found significant differences in the ` physical ' subscales in both SF-36 and GIQLI as well as differences in body image in favour of minimal invasive procedures . The fact that significant differences were found in the ` physical ' subscales in both questionnaires illustrates construct validity between both health status instruments . Literature A few other studies have compared health status after LC and SIC -LSB- 18 -- 20 -RSB- . Two studies found that the laparoscopic technique was associated with a more rapid improvement in health status after cholecystectomy compared with the small-incision technique -LSB- 18 , 19 -RSB- . One study found no differences at all between both techniques -LSB- 20 -RSB- . However , it is difficult to draw conclusions from three studies that used different questionnaires and suffer several methodological flaws . None of the mentioned studies combined the SF-36 and GIQLI as advised by evidence-based guidelines -LSB- 21 -RSB- . Barkun studied 35 and 23 patients in the LC and SIC groups , respectively , and used the same GIQLI as we did in addition to the Nottingham health profile -LRB- NHP -RRB- and a visual analogue scale -LRB- VAS -RRB- for health -LSB- 18 -RSB- . Allocation concealment was unclear , no blinding was used , and eight dropouts occurred in their rather small , preliminary stopped trial . They used cumulative totals of both GIQLI and NHP data instead of using subscales . Changes in one dimension might be offset by changes in other dimensions . Both questionnaires have more than one dimension -LRB- the cumulative total -RRB- ; subscales indeed provide the advantage of additional information on several dimensions . As a rather small number of patients were included -LRB- the trial was stopped preliminary -RRB- , no subscales were assessed , and no considerations were given to the construct or divergent validity of both questionnaires , their conclusion that LC was associated with a significantly quicker return to ` good health ' seems inappropriate based on their results . McMahon compared health status in 151 and 148 laparoscopic and small-incision cholecystectomy patients respectively using the SF-36 health survey questionnaire and the hospital anxiety and depression scale -LRB- HADS -RRB- -LSB- 19 -RSB- . Generation of the allocation sequence in their trial was unclear and no blinding was used . They found that patients recovering from LC enjoyed significantly better health 1 and 4 weeks after the operation compared with those recovering from SIC , but no significant difference was found at 12 weeks . The absence of preoperatively baseline measurements and the absence of considerations on the construct or divergent validity of the questionnaires make conclusions about postoperative data uncertain . Differences in SF-36 and HADS correlated with differences in return to domestic and leisure activities , but were not translated in differences in paid activity . Squirrell used the NHP in 100 patients -LRB- 50 in each group -RRB- preoperatively , and 3 weeks and 6 months postoperatively -LSB- 20 -RSB- . This was the only study that used blinding in their methods . Generation of the allocation sequence in their trial was unclear . At no time there was a significant difference between the two groups . The study used a rather small sample size , and unfortunately they did not use a disease-specific questionnaire , but only one generic questionnaire . They concluded that it is necessary to take a broader view of health and not concentrate simply on pain when assessing postoperative recovery . In our study , no significant differences were found between LC and SIC using both generic and disease-specific health status as well as body image with response in approximately 80 % of patients . The response rate of 77.4 % at 3 months follow-up may represent a possible source of bias . However , the nonresponders were comparable to those who remained in the study with regard to complications , operative time , hospital stay , return to work , and baseline scores of questionnaires . Moreover , our response rate is in line with the response rates in the studies of Barkun et al. -LRB- 58 % -RRB- and McMahon et al. -LRB- 78 % -RRB- . We conclude that there are no differences between both operative techniques regarding health status . The only exception is that in the SF-36 subscale perceived health change we found a difference between LC and SIC , which appeared to be caused by the scores at 2 and 6 weeks postoperatively and disappeared at 3 months follow-up . LC patients reported a larger health change . However , in the evaluation of 17 aspects of health status , only one difference was found . Moreover , this difference in perceived health change was not reflected in an earlier return to work in LC . In contrast , SIC patients returned to work quicker than LC patients , although this different was not significant . Therefore , our overall interpretation is that there are no differences between LC and SIC . The comparable ` physical ' subscales in SF-36 and GIQLI , which are supposed to measure the same effect , are both significantly different in the minimal invasive versus conversions comparison illustrating construct validity of both questionnaires . Subscales on different subjects in the questionnaires illustrate divergent validity . Significant differences between minimal invasive and converted procedures illustrate that the questionnaires used are able to measure what they are intended to do . Conclusion In our randomised trial with adequate generation of the allocation sequence , concealment of allocation , blinding , and follow-up we used both a generic and a disease-specific questionnaire in addition to a body image questionnaire . There is no significant difference in health status measured with SF-36 , GIQLI , and BIQ between laparoscopic and small-incision cholecystectomy -LRB- applying the intention-to-treat principle -RRB- . Additional calculations showed a significant difference between minimal invasive LC or SIC procedures and procedures converted to the classical open cholecystectomy .

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