Table 4.

Reliability of partnership date questions for most recent sex partner among sexually active female online daters in the US, 2007–2012

Agreement between categorical and continuous date questions
	N	Weighted kappa (κ)a	(95% CI)b
Date of first sex	613c	0.56	(0.48, 0.64)
Date of last sex	580d	0.93	(0.91, 0.94)
Agreement between continuous date questions on 2 consecutive questionnaires within 6 months
	N	Intraclass Correlation Coefficient	(95% CI)
		(ICC)
Date of first sex	199	0.89	(0.86, 0.92)

^aQuadratic weights were assigned.

^bBootstrap methods were used to obtain a bias corrected 95% CI.

^c3 women did not provide a response for the categorical variable. For the continuous date, 2 women provided implausible dates that were recoded to the nearest day (September 31^st was changed to September 30^th and February 29^th was changed to February 28^th), 20 women did not provide a response, and 14 women provided future dates that were excluded. No women were missing both the categorical and continuous date variables.

^d28 women did not provide a response for the categorical variable. For the continuous date, 27 women did not provide a response, 12 women were excluded for providing future dates, and 16 were excluded for listing a continuous date that was more than one year ago and therefore did not match the categorical response options. Thirteen women were missing both the categorical and continuous date variables.