Meta-analysis of well-designed nonrandomized comparative studies of surgical procedures is as good as randomized controlled trials.

[1]  J. Young,et al.  META‐ANALYSIS OF NON‐RANDOMIZED COMPARATIVE STUDIES OF THE SHORT‐TERM OUTCOMES OF LAPAROSCOPIC RESECTION FOR COLORECTAL CANCER , 2007, ANZ journal of surgery.

[2]  M. Braga,et al.  Laparoscopic versus open colorectal surgery : cost-benefit analysis in a single-center randomized trial , 2019 .

[3]  R. Veldkamp,et al.  Laparoscopic surgery versus open surgery for colon cancer : short-term outcomes of a randomised trial , 2022 .

[4]  Philip Quirke,et al.  Short-term endpoints of conventional versus laparoscopic-assisted surgery in patients with colorectal cancer (MRC CLASICC trial): multicentre, randomised controlled trial , 2005, The Lancet.

[5]  M. Solomon,et al.  Meta‐analysis of short‐term outcomes after laparoscopic resection for colorectal cancer , 2004, The British journal of surgery.

[6]  J. Fleshman,et al.  A comparison of laparoscopically assisted and open colectomy for colon cancer. , 2004, The New England journal of medicine.

[7]  K. Slim,et al.  Methodological index for non‐randomized studies (MINORS): development and validation of a new instrument , 2003, ANZ journal of surgery.

[8]  W. Rankin Babies and bathwater. , 2001, Journal of pediatric nursing.

[9]  A. Hartz,et al.  A comparison of observational studies and randomized, controlled trials. , 2000, The New England journal of medicine.

[10]  J. Concato,et al.  Randomized, controlled trials, observational studies, and the hierarchy of research designs. , 2000, The New England journal of medicine.

[11]  A D Oxman,et al.  The unpredictability paradox: review of empirical comparisons of randomised and non-randomised clinical trials , 1998, BMJ.

[12]  M J Campbell,et al.  Choosing between randomised and non-randomised studies: a systematic review , 1998, BMJ.

[13]  R. J. Hayes,et al.  Empirical evidence of bias. Dimensions of methodological quality associated with estimates of treatment effects in controlled trials. , 1995, JAMA.

[14]  T C Chalmers,et al.  Bias in treatment assignment in controlled clinical trials. , 1983, The New England journal of medicine.

[15]  T C Chalmers,et al.  Randomized versus historical controls for clinical trials. , 1982, The American journal of medicine.

[16]  G. W. Snedecor STATISTICAL METHODS , 1967 .

[17]  T A Sheldon,et al.  A systematic review of comparisons of effect sizes derived from randomised and non-randomised studies. , 2000, Health technology assessment.

[18]  A. Carr,et al.  Primary total hip replacement surgery: a systematic review of outcomes and modelling of cost-effectiveness associated with different prostheses. , 1998, Health technology assessment.

[19]  R. McLeod,et al.  Clinical studies in surgical journals—have we improved? , 1993, Diseases of the colon and rectum.