K. Slim MD, FACS; E. Nini MD; D. Forestier MD; F. Kwiatkowski PhD; Y. Panis MD, PhD; J. Chipponi MD, PhD.
Methodological index for non-randomized studies (MINORS): development and validation of a new instrument
Article first published online: 8 SEP 2003
ANZ Journal of Surgery
Volume 73, Issue 9, pages 712–716, September 2003
How to Cite
Slim, K., Nini, E., Forestier, D., Kwiatkowski, F., Panis, Y. and Chipponi, J. (2003), Methodological index for non-randomized studies (MINORS): development and validation of a new instrument . ANZ Journal of Surgery, 73: 712–716. doi: 10.1046/j.1445-2197.2003.02748.x
- Issue published online: 8 SEP 2003
- Article first published online: 8 SEP 2003
- Accepted for publication 13 May 2003.
- comparative study;
- methodology index;
- non-randomized study
Background: Because of specific methodological difficulties in conducting randomized trials, surgical research remains dependent predominantly on observational or non-randomized studies. Few validated instruments are available to determine the methodological quality of such studies either from the reader's perspective or for the purpose of meta-analysis. The aim of the present study was to develop and validate such an instrument.
Methods: After an initial conceptualization phase of a methodological index for non-randomized studies (MINORS), a list of 12 potential items was sent to 100 experts from different surgical specialities for evaluation and was also assessed by 10 clinical methodologists. Subsequent testing involved the assessment of inter-reviewer agreement, test-retest reliability at 2 months, internal consistency reliability and external validity.
Results: The final version of MINORS contained 12 items, the first eight being specifically for non-comparative studies. Reliability was established on the basis of good inter-reviewer agreement, high test-retest reliability by the κ-coefficient and good internal consistency by a high Cronbach's α-coefficient. External validity was established in terms of the ability of MINORS to identify excellent trials.
Conclusions: MINORS is a valid instrument designed to assess the methodological quality of non-randomized surgical studies, whether comparative or non-comparative. The next step will be to determine its external validity when used in a large number of studies and to compare it with other existing instruments.