Reporting the results of meta-analyses: a plea for incorporating clinical relevance referring to an example.

BACKGROUND CONTEXT

The results of meta-analyses are frequently reported, but understanding and interpreting them is difficult for both clinicians and patients. Statistical significances are presented without referring to values that imply clinical relevance.

PURPOSE

This study aimed to use the minimal clinically important difference (MCID) to rate the clinical relevance of a meta-analysis.

STUDY DESIGN

This study is a review of the literature.

PATIENT SAMPLE

This study is a review of meta-analyses relating to a specific topic, clinical results of cervical arthroplasty.

OUTCOME MEASURE

The outcome measure used in the study was the MCID.

METHODS

We performed an extensive literature search of a series of meta-analyses evaluating a similar subject as an example. We searched in Pubmed and Embase through August 9, 2016, and found articles concerning meta-analyses of the clinical outcome of cervical arthroplasty compared with that of anterior cervical discectomy with fusion in cases of cervical degenerative disease. We evaluated the analyses for statistical significance and their relation to MCID. MCID was defined based on results in similar patient groups and a similar disease entity reported in the literature.

RESULTS

We identified 21 meta-analyses, only one of which referred to MCID. However, the researchers used an inappropriate measurement scale and, therefore, an incorrect MCID. The majority of the conclusions were based on statistical results without mentioning clinical relevance.

CONCLUSIONS

The majority of the articles we reviewed drew conclusions based on statistical differences instead of clinical relevance. We recommend introducing the concept of MCID while reporting the results of a meta-analysis, as well as mentioning the explicit scale of the analyzed measurement.