Comparison of the operative time for open door laminoplasty using titanium plate spacers or hydroxyapatite block spacers: a retrospective study

Table 4 Regression coefficient of using TP spacers

Model	Coefficient	95% confidence interval	p value
Crude	− 30	− 30 to − 6.4	< 0.001
Multiple regression analysis without using PS	− 30	− 42 to − 17	< 0.001
PS controlled multiple regression analysis	− 35	− 51 to − 20	< 0.001
PS matching	− 38	− 52 to − 23	< 0.001

Abbreviations: TP titanium plate, PS propensity score
The propensity score was calculated by a logistic regression model using the following variables: sex, age, body mass index, American Society of Anestheologists physical status, ossification of posterior longitudinal ligament, diabetes mellitus, use of antiplatelet or anticoagulant medicine, level of operator, number of decompressed laminae, laminoplasty of dens, hemoglobin, platelet, estimated glomerular filtration rate, prothrombin time-international normalized ratio, activated partial thromboplastin time

ISSN: 1749-799X