Needle knife therapy for cervical spondylotic radiculopathy: A systematic review and meta-analysis

Table 1 Summary of findings for Grading of Recommendations Assessment, Development and Evaluation ratings

Outcome measure	Quality of evidence assessment (GRADE)
	No of patients (effect size)	Risk of quality of bias1	Inconsistency2	Evidence6	Indirectness3	Imprecision4	Publication5
Effective rate	1184	Serious	Very low	Low	Not serious	Very low	Very low
VAS	1184	Low	Very serious	Low	Not serious	Very low	Very low
NDI	734	Low	Very serious	Low	Not serious	Very low	Very low
YT20	246	Serious	Very serious	Low	Not serious	Not serious	Very low

¹Risk of bias based on the Cochrane risk of bias tool. This tool assesses selection bias, performance bias, detection bias, attrition bias, and reporting bias.

²Downgraded if there was a substantial unexplained heterogeneity. Downgraded one level for serious inconsistency: 50% < I² ≤ 75%; downgraded two level for very serious inconsistency: 75% < I² < 100%.

³Downgraded if there were factors present relating to the participants, interventions, or outcomes that limited the generalizability of the results.

⁴Downgraded if the number of participants are very small (n < 200).

⁵Downgraded if there was an evidence of publication bias using Egger’s test.

⁶Given that all included studies were meta-analyses of randomized controlled trials, the evidence certainty was initially rated as high for all outcomes and sub- sequently downgraded according to predefined criteria. Quality was graded as high, moderate, low, and very low.

GRADE: Grading of Recommendations Assessment, Development and Evaluation; VAS: Visual Analog Scale; NDI: Neck Disability Index; YT20: Yasushi Tanaka cervical spondylitis symptom scale 20 scores.