We assessed the quality of evidence for the outcomes of the included studies using the GRADE approach (GRADE 2008).
Quality of evidence was graded using the GRADE approach.
Studies reporting on the primary outcome of knee flexion were graded according to the GRADE approach.
This will be judged using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.
Quality of the evidence was not high when assessed by the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach.
These limitations are the factors used to evaluate the level of evidence according to the GRADE approach [ 17].
Under the GRADE approach, an unexplained inconsistency such as this decreases the quality level of a body of evidence [ 27].
The GRADE approach was used to test the overall quality of evidence (QoE) [15].
Also, we used the GRADE approach to summarize the quality of evidence for each outcome [6].
The GRADE approach and the ISEK guideline contributed to identify important flaws in the literature.
However, the overall quality of evidence was rather limited and rated 'low,' using the GRADE approach.
