XXXX : a systematic review of observational studies.

@entity1 @entity8407 @entity5 @entity12120 @entity1141
UNASSIGNED: The aim of this systematic review was to ascertain the @entity8407 and the associated risk factors. METHOD: Published literature was searched through several search engines from 1960 to the end of December 2013. The inclusion criteria included ' @entity12120 ', 'pre- @entity5 ', 'malignant transformation', 'follow-up' and 'outcome'. Two reviewers extracted the data independently and also assessed the quality of evidence. RESULTS: The search strategy resulted in 1032 abstracts or full-text articles, of which 24 met the inclusion criteria. There was much variation in the definitions used by the various authors in their original reports to @entity8407 or in the criteria used to recruit their @entity1 for follow-up. The estimated overall (mean) malignant transformation rate for the total population described in these 24 studies amounts to 3.5% (405/11423), with a wide range between 0.13% and 34.0%. Based on the evidence presented, the features that stand out as significant determinants contributing to malignant potential of OL include advanced age, female sex, @entity12120 exceeding 200  mm(2) , non-homogeneous type (eg. erythroleukoplakia) and the higher grades of @entity1141 . CONCLUSION: The review indicates that drawing meaningful evidence-based conclusions are difficult from retrospective studies of this nature. However, many of the determinants exposed in the review require further investigation by well-designed prospective studies.
