Comparison of smith-petersen osteotomy, pedicular subtraction osteotomy, and poly-segmental wedge osteotomy in treating rigid thoracolumbar kyphotic deformity in ankylosing spondylitis a systematic review and meta-analysis

Table 2 Assessment of studies

Categories	Items	Lazennec¹⁵	Qiu²⁰	Willems²⁷	Cho⁵	Chang⁴	Zhu²⁹	Arun¹	Zhu³⁰
Selection	Representativeness of the Exposed Cohort	Not described	Not described	Not described	Not described	Not described	Not described	Not described	Not described
	Selection of the Non-Exposed Cohort	The same population	The same population	The same population	The same population	The same population	The same population	The same population	The same population
	Ascertainment of Exposure	Surgical document	Surgical document	Surgical document	Surgical document	Surgical document	Surgical document	Surgical document	Surgical document
	Outcome of Interest Was Not Present at Start of Study	Sure	Sure	Sure	Sure	Sure	Sure	Sure	Sure
Comparability	Comparability of Cases and Control	With confounding factors	With confounding factors	With confounding factors	With confounding factors	With confounding factors	With confounding factors	With confounding factors	With confounding factors
Outcome	Assessment of Outcome	Reliable	Reliable	Reliable	Reliable	Reliable	Reliable	Reliable	Reliable
	Was Follow-Up Long Enough for outcomes to occur?	Not described	Yes	Yes	Yes	Yes	Yes^a	Yes	Yes
	Loss of Follow Up	Full follow-up	Not described	Full follow-up	Full follow-up	Full follow-up	Full follow-up	Full follow-up	Full follow-up
Score		5	4	6	6	6	5 or 6^b	6	6

Note: ^a Zhu reported at least 3-month follow-up which satisfied the observation of immediate correction of lordosis and neural symptom but not bony union; ^b 5 points for assessment of bony union and 6 for lordosis correction. The full mark is 8 points

ISSN: 1471-2482