TRAIL gene 1595C/T polymorphisms contribute to the susceptibility and severity of intervertebral disc degeneration: a data synthesis

Table 1 Characteristics of individual studies

Authors	Year	Country	Ethnicity	Gender (M/F)		Age, mean (SD)		Matching	Control source	Genotyping method	IDD diagnosis	IDD severity standard	Study quality
				Case	Control	Case	Control
Zhang [10]	2015	China	Han Chinese	198/114	121/75	49.54(8.87)	48.65(8.12)	Age and gender	Healthy subjects	PCR-RFLP	Symptoms, MRI	Schneiderman’s classification	11
Du [8]	2015	China	Han Chinese	73/80	62/69	40.2(5.1)	38.6(5.0)	Age and gender	Healthy subjects	PCR-RFLP	Symptoms, MRI	Schneiderman’s classification	11
Xu [9]	2015	China	Han Chinese	54/46	58/42	59	49	Age and gender	Healthy subjects	PCR- RFLP	Symptoms, MRI	Schneiderman’s classification	10

M male, F female, SD standard deviation, IDD intervertebral disc degeneration, PCR-RFLP polymerase chain reaction–restriction fragment length polymorphism, MRI magnetic resonance imaging

ISSN: 1471-2474