TABLE II.

Results of Genealogical Index of Familiality Test of Excess Relatedness

	No. of Patients	Case Overall GIF*	Mean Control GIF*	Empirical P Values*
Phenotype				Overall GIF	Distance GIF
Rotator cuff disease†	3091	2.86	2.52	<0.001	0.848
Early onset of rotator cuff disease‡	652	2.53	1.84	0.001	0.004

^*GIF = Genealogical Index of Familiality.

^†All individuals who had been diagnosed with a rotator cuff tear or treated with rotator cuff surgery, including the early onset subset.

^‡Only individuals who had early onset, which is defined as an age of less than forty years at the time of diagnosis.