Responsiveness of quality of life instruments for the comparison of minimally invasive cholecystectomy procedures

Background: Traditional metrics of postoperative outcomes (morbidity and mortality) are not useful to compare minimally invasive procedures with each other. Patient reported outcomes, such as quality of life (QOL) scores, offer an alternative approach. Compared with a large body of data in cancer treatment, the responsiveness of these instruments for minimally invasive surgery is not well described. To better define expected differences, we analyzed the reported QOL outcomes in randomized, controlled trials (RCTs) comparing single and four-port laparoscopic cholecystectomy. Methods: Searching Medline, Embase, Psychinfo, Scopus, and the Cochrane Library (1946 to Jan 2012), two independent reviewers identified RCTs comparing single with four-port cholecystectomy in adult patients using perioperative QOL assessments. The quality of the studies was assessed regarding trial design and QOL reporting. RevMan was used for mathematical analysis of the pooled outcome data using a random-effects model. Standardized mean difference estimation was utilized when pooling studies reporting different QOL tools. Statistical heterogeneity was assessed using χ² and I². Results: Of 743 citations, 37 RCTs were identified. Five studies with a total of 502 patients compared single with four-port cholecystectomy on QOL and were included. Pooled analysis was performed using preoperative and 1-month postoperative outcomes. At 1 month postoperatively, the reported effect size of perioperative QOL changes was up to 5 points (~1/2 SD) on the global SF 12 score. The largest difference in change of perioperative physical functioning was 9.9 points (~1 SD). No difference between the treatments was demonstrated. Conclusions: Reporting of QOL may improve the comparison of minimally invasive surgical procedures. This systematic review reports clinically important changes and did not demonstrate a difference between treatments at 1 month postoperatively. The optimal timing and trial design for QOL tools in this setting needs to be defined further.