. Author manuscript; available in PMC: 2014 Sep 11.

Published in final edited form as: Ultrasound Obstet Gynecol. 2013 Jan 8;41(2):152–161. doi: 10.1002/uog.12344

Table 2.

Interobserver agreement and correlation in classifying and measuring cervical tissue strain in a sub-sample of 20 women (120 measurements- 6 per participant)

Region	View	Simple Kappa			Weighted Kappa			Exact Agreement^ˆ	Pearson Correlation Coefficient^*
Region	View	Value	95% CI		Value	95% CI		Exact Agreement^ˆ	Pearson Correlation Coefficient^*
Endocervical Canal	Internal	0.43	0.09	0.77	0.56	0.24	0.87	65%	0.81
	External	0.26	-0.06	0.59	0.30	-0.06	0.66	50%	0.83
	Sagittal	0.44	0.13	0.76	0.43	0.09	0.78	65%	0.53
Complete Cervix	Internal	0.67	0.39	0.95	0.68	0.40	0.97	80%	0.51
	External	0.46	0.10	0.81	0.46	0.09	0.83	68%	0.72
	Sagittal	0.32	0.02	0.61	0.31	0.01	0.61	57%	0.57
Total		0.43	0.30	0.56	0.46	0.32	0.60	65%	0.73

Note:

^ˆ

Exact agreement characterizes categorical soft/average/stiff tissue classifications.

The Pearson correlation coefficient characterizes interobserver correlation for cervical tissue strain measurements rounded to the nearest tenth decimal place.